Cleaning System Maintenance


The Equipment Check
The Comprehensive Equipment Check is a step-by-step procedure for determining if a cleaning system is in proper working order. This check goes through the cleaner’s major systems helping to detect maintenance needs and potential service problems. The equipment check should be performed monthly or after any period of particularly heavy usage, especially if the equipment was used in a harsh or hostile environment.


The Operator & Equipment Problems
The greater the operator access to the equipment and its controls, the more important the equipment check because operator abuse and maladjustment are two major causes of cleaning equipment problems. A portable unit with easily accessible controls or adjustments will generally wind up causing more problems than a stationary natural gas unit that is in an enclosed area with limited operator access. (The stationary natural gas or LP unit also eliminates two other major equipment problems, dirty fuel and debris in the water supply since the system will be hard-plumbed into both supplies).


The number of operators having access to a unit will also contribute to the frequency of problems. A unit with many operators will usually have more problems than a unit with a single operator assigned to it. The best way to keep operators from tinkering unnecessarily with adjustments is to see that the equipment is running properly, providing adequate pressure, flow and heat at all times. Regular checks will help you achieve this goal.

Clean Equipment
Whenever equipment is checked, it should be cleaned thoroughly. In all cases except where it is absolutely impossible, the equipment should be cleaned before the check is performed. Having the machine clean will allow you to see all components clearly, easily notice any leaks and help keep you from getting dirty. It is usually a good idea to involve the operator in cleaning the machine, as well as to walk him through the monthly comprehensive check with you a few times so that he will be aware of potential equipment problems and proper maintenance procedures.

Major Hazards
One very important reason to regularly inspect equipment is to reduce the possibility of accidents by identifying and eliminating potential hazards. When inspecting equipment, keep an eye out for potential hazards. High pressure cleaning equipment can present a number of such hazards. These hazards include:
· Electrocution
· Boiler explosion
· Fire
· Scalding

Additional Hazards
Additional hazards can result from the use of the equipment. These hazards include: penetration of the skin with high pressure spray, slipping on wet surfaces, loss of control of the spraying lance and contact with harsh chemicals. All cleaning equipment should be designed and installed to minimize these potential hazards to the greatest extent possible. Hazards can be reduced in two ways: By selecting equipment with adequate safety features and by training the operator to avoid the potential hazards. Often training simply consists of instructing the operator as to how and when to properly take advantage of equipment safety features or use proper personal protective equipment.

The majority of high-pressure cleaners are powered by electric motors. Since these cleaners spray water, they are generally operated in a wet or at least a damp environment. Electricity and water are a potentially dangerous combination. Operation of electrically unsafe high pressure cleaning equipment has been attributed as the cause of numerous recorded incidences of electrocution.

These Measures Include:
· Weatherproof or waterproof electronic connections or enclosures.
· Totally enclosed or washdown duty electric motor.
· Ground fault circuit interrupter to prevent electrocution due to residual or leakage current.
· Low voltage controls to protect the operator from contact with the equipment’s substantially higher operating voltage.
· Double insulated electrical components.
· Adequate grounding.

Note: Most of these measures are required by electrical codes and Occupational Safety and Health Administration (OASH) regulations for any electrical installations outdoors or in damp environments.

Boiler Explosion
A hot water cleaner is essentially a small, high-pressure boiler with a heat input, which often exceeds 200,000 Btu. Most high-pressure cleaner boilers are manufactured to fit a specific exemption from very strict American Society of Mechanical Engineers (ASME) standards, which apply to the design and construction of almost all boilers, used in the United States. While non-adherence to these standards does not necessarily make the high pressure cleaner boiler unsafe, the situation makes it imperative that adequate control and safety devices be installed on the boiler to prevent or minimize the hazard of violent steam explosion which can cause damage to property, injury or even death.

Boiler controls are very important to work place safety, since a stoppage of water flow through the cleaner can cause super heating of water trapped in the coil and a violent and highly dangerous steam explosion can result. Before adequate safety standards were set, literally thousands of housewives were seriously injured by accidents involving pressure cookers. The high pressure cleaner has a far more powerful boiler operating at a much higher pressure than a simple stove-top pressure cooker and the potential hazard is very much proportional to the size of the boiler.

Any high-pressure cleaner boiler system should be equipped, at a minimum, with a control or safety device which stops boiler operation when a maximum temperature is reached and a control which stops burner operation when the flow of water through the boiler coil ceases. This is a bare minimum of redundancy for safe boiler operation. The safest configurations will include additional control or safety devices. Such devices may include a timed shutoff, which completely stops equipment operation after a set period of nonuse.

All hot water cleaners (with the exception of electric water heaters) use some kind of fuel for the burner. This fuel may be kerosene, fuel oil or natural or liquefied propane gas. Engine powered machines also require gasoline or diesel fuel for the engine. If these fuels are not safely handled, and if burner firing (especially with natural or LP gas machines) is not properly controlled, the equipment has the potential to pose a fire hazard. Use of gasoline-engine powered equipment with a LP gas-fired, continuous pilot burner is extremely dangerous since the operator may attempt to fuel the gas engine while the burner pilot is operating, creating a grave and immediate fire hazard.

Water in excess of 120 degrees Fahrenheit presents the hazard of scalding any person it comes in contact with. Cleaner output is usually in the 140 to 200 degree severe scalding. However, some cleaning jobs, especially oil and grease removal, are performed more efficiently at temperatures toward the high end of this range.

Note: Water temperature falls fairly rapidly as the distance from the nozzle increases. A foot from the nozzle, water output that was initially 140 degrees Fahrenheit when it left the nozzle may be 120 degrees Fahrenheit or lower. The two main protections against scalding are operator training in precautions to prevent scalding and adjustable temperature control. Water output should never be any hotter than needed to perform a particular cleaning task. Output of 140 degrees Fahrenheit is usually adequate for most cleaning jobs. Any splash back, which might hit the operator, will be below the 120 degree scalding threashold if a lance of 36 inches or longer is used. Even if higher output temperatures are used, the 36-inch lance will still allow for a substantial splash back temperature drop. Personal protective gear such as waterproof boots and clothing will also help reduce the possibility of scalding.

Loose Lance
For every action there is an equal and opposite reaction. The water spray from the lance tends to propel the lance backwards, much like a rocket motor. The more powerful the spray, the more force with which the lance is propelled. If there is no trigger control and the operator looses control of the lance, it will flail about, damaging property and causing injury, until the water flow is shut off. Trigger gun control prevents this hazard. When the operator pulls the trigger, a valve in the gun opens and water flows through the spray nozzle. When the trigger is released, the valve closes and water flow stops. This is essentially a deadman control, that is whenever the positive action of squeezing the trigger ceases, the control automatically defaults to the safe or no-flow setting. Trigger gun control is one of the most important defaults to the safe or no-flow setting. Trigger gun control is one of the most important safety features on any high pressure cleaner. However, many cleaners, especially older or less expensive models, are not equipped with trigger gun control and are potentially quite dangerous.

Personal Protective & Safety Equipment
It is important to keep the proper personal protective and safety equipment on hand. The reduction of the risk of injury and property damage may be reflected in insurance rates. Here are some recommendations for personal protective and safety equipment. When these items may conform to a standard, the appropriate ANSI or OSHA standard is listed.
· Chemical goggles
· Impact goggles
· Portable eye wash station
· Hard hat
· Ear plugs
· Gloves
· Chemical resistant boots with steel toe
· Rain suit
· Fire extinguisher (ABC rated)
· Fuel cans (UL listed and in compliance with OSHA regulations)

Warning: Using an electric motor-driven cleaner to clean itself presents a danger of electrocution.

The Maintenance Report Form & Maintenance Check
A maintenance report form will help you keep track of your regular equipment checkups. If the unit has a gasoline engine, this record and the engine maintenance record should be kept together. A sample maintenance record form is shown here. A sample maintenance record can be created on a piece of lined notebook paper. All maintenance records should be kept near the cleaner in a safe, watertight place. Make sure these records are kept up-to-date and equipment service problems will be reduced.

Keep A Complete Record
The maintenance report form should be filled out whenever a comprehensive check is performed on the equipment. The sample form is filled out vertically, from the top of the page downward. At the start of each check or tune-up the date should be entered at the top of the column where information for that check will be recorded. Each time a check is completed, a full column should be used.

The column below the date includes blanks for each of the check’s steps. Only one of three characters "S, C, or U" should be placed in these boxes. These characters stand for "satisfactory," "unsatisfactory," and "corrected." Satisfactory should be indicated if the portion of the system being checked requires no action to be in acceptable condition. Corrected should be indicated if action is taken to bring that portion of the system into satisfactory condition. Unsatisfactory should be indicated if corrective action is needed and for some reason is not taken. If a portion of the check is not made, nothing should be written in that blank.

The Check In Brief

Before Starting The Machine:
1. Inspect the power cord and wiring for damage.
2. Check the safety ground.
3. Check the water supply.
4. Check the pump oil level.
5. Check the discharge hose.
6. Check drive belts.
7. Check fuel supplies.
8. Check for scale deposit.
9. Check for sooting.

Start The Cleaner:
10. Check for fluid leaks.
11. Check system pressure & unloader operation.
12. Check for proper chemical delivery.
13. Check the trigger gun.
14. Check the spray lance.
15. Check the spray nozzle.
16. Check for proper burner operation.

Shut Off The Cleaner:
17. Check for adequate & proper chemicals.

Wipe Off The Cleaner And Spray It With WD-40.

The Comprehensive Equipment Check – Line By Line


Following are instructions on how to perform and record an equipment check using the sample maintenance report form. The steps need not be performed in this order, so long as all of the items mentioned are checked. However, the order in which the form goes through the cleaner is a logical one that may help eliminate extra steps. The equipment check services to monitor not only equipment operation and maintenance needs but pays careful attention to important safety considerations as well.

Line 1: Inspect The Power Cord And Wiring For Damage.


If extension cords are used, inspect them as well. Check to see that all power or extension cords have operable grounding prongs and have the proper plug for the units power requirements. In many cases a 115-volt cleaner with 20 amp draw will have been fitted with a 15 amp plug since such outlets are more common even on circuits with 20 amp breakers. This modification violates electrical codes and safety regulations. An electrician should be instructed to see that the proper plugs and outlets are installed.

If a power cord appears to be damaged or if there is an ungrounded extension or power cord, have the cord replaced. Do not operate a cleaner that has a potential problem. If a lightweight extension cord is used or if a very long or multiple extension cords are used, you should replace the cord or cords with a cord of the proper gauge to meet equipment demands to avoid the danger of the motor overheating. See the wire size chart in the Electrical Section for proper wire sizes for cleaning system power requirements.

Check to see that all electrical plugs are properly plugged in and are in dry environments. If an extension cord or cords are employed, make sure that all connections between the plugs are out of any standing water or any area where flowing water might be found once the equipment is in operation. In some instances waterproof or weatherproof connectors may be called for.


Safety standards now require that all new 115-volt cleaners be fitted with Ground Fault Circuit Interrupters. If the equipment is not fitted with a GFCI, as is required by the National Electrical Code on new equipment, an outlet with a GFCI or a plug-in GFCI may be recommended. Check electrical wiring. If wiring is visible, inspect for burned spots or exposed wire, which could cause shorts. (Any wiring, which is visible, may also be exposed to moisture). All visible wiring should be insulated and connections should, at a minimum, be protected with electrical tape. Do not operate equipment with burned insulation or electrical wire exposed. (This applies to gas engine-driven oil-fired equipment as well as electric motor-driven units since the burner has a high voltage ignition).

Line 2: Check The Safety Ground.


It is always a good idea to confirm proper grounding even if a GFCI is installed in the cord or in the unit (some stationary units have GFCI’s installed in the electrical box). In fact, regular grounding checks are required in workplaces where federal Occupational Safety and Health Administration (OSHA) regulations apply.

Proper and effective equipment grounding is an absolute requirement for safe operation of any electrically powered equipment. This is especially true for high pressure cleaning equipment, which is normally operated in damp or wet conditions. Water and electricity do not mix! A faulty ground can be fatal! OSHA requires that all electrically powered equipment grounding conductors must be electrically continuous and must be regularly checked for continuity. These requirements are part of the Assured Equipment Grounding Conductor Program.

The Regulatory Requirements
OSHA 1910.304 (d) The following tests shall be performed on all cord sets, receptacles which are not a part of the permanent wiring of the building or structure and cord-and plug-connected equipment required to be grounded:
1.) All equipment grounding conductors shall be tested for continuity and shall be electrically continuous.
2.) Each receptacle and attachment cap or plug shall be tested for correct attachment of the equipment-grounding conductor. The equipment-grounding conductor shall be connected to its proper terminal.

All Required Tests Should Be Performed:
1.) Before first use.
2.) Before equipment is returned to service following any repairs.
3.) Before equipment is used after any incident which can be reasonably suspected to have caused damage (for example, when a cord set is run over).
4.) At intervals not to exceed three months, except cord sets and receptacles that are fixed and not exposed to damage, these should be tested at intervals not exceeding six months.

Conducting The Safety Ground Check
To conduct a grounding check, simply test for continuity between the grounding leg on the equipment plug and the equipment frame. Test from the round safety-grounding prong on the plug to exposed metal on the equipment frame. Continuity should be registered between these two points or a grounding problem is indicated. Testing can be accomplished with either a multimeter set to measure continuity or with a test light.

Line 3: Check The Water Supply.


Check to see that the water supply to the cleaner is clean and adequate. If you must hook up the cleaner to check it out, make sure that you flush any debris from the garden hose before starting the cleaner. Adjust water flow at the hydrant so that an adequate amount of water is running to the machine. Since many cleaners have output volumes of about 3 gpm or less and most municipal water supplies are in the 6 gpm range, the inlet water supply might not need to be set on maximum, depending upon the needs of the cleaning system.

Check all inlet or inline water filters for debris. Clean or replace as necessary. If the cleaning system has a float tank, check float tank operation. Allow the float tank to fill up and see if the float valve shuts off the water supply to the unit when the proper water level in the float tank is reached.

Check the float tank for debris. Most float tanks are equipped with covers to prevent the entry of large foreign objects such as leaves and cigarette or candy wrappers, which can block the outlet of the float tank. A blocked outlet can defeat a vacuum switch used as a boiler control. If the system uses a water tank, check to see that the tank is full to the level you will need for the washing you are planning to do. If the cleaner is hard-plumbed into the water supply, it will not be necessary to check water delivery.

Line 4: Check The Pump Oil Level.


Using either the sight glass or dipstick on the pump crankcase, make a visual check to make sure that the pump oil level is adequate. Also check to see if the pump oil is milky colored. This discoloration indicates that the oil has been contaminated with water.

If the level is low, oil should be added or the oil changed. Check the maintenance record for the last oil change. If no discoloration is observed, oil changes every six months are usually adequate for crankcase type pumps. Special pump oil is available although standard, non-detergent 30 weight motor oil is adequate for most pumping applications. Specialty pump oil may come with a warranty against oil-related pump problems.

If the oil is discolored or milky, the pump oil should be changed. To determine if water contamination of the crankcase oil is the result of condensation within the crankcase or leakage past the oil seals the pump oil should be checked again after several hours of system operation. If the oil is again discolored the problem is likely to be the oil seals and oil seal replacement is indicated. If oil is added, suggest using the approved product stocked on your vehicle. Instruct the operator to monitor the oil for water contamination on a daily basis (each eight hours of equipment operation).

Line 5: Check The Discharge Hose.


Carefully inspect the high-pressure hose. Look for cover damage. Check for damaged couplings. If cover is damaged so that reinforcing wire is exposed the hose should be withdrawn from service. If coupling is damaged or loose suggest a new coupling. If cover is abraded or scuffed, suggest that a spare hose is needed. Point out any damage to the operator and to his supervisor if hose damage is recurring.

If any hose wear or evidence of abuse is visible, remove the hose from service and have it replaced. With the exception of cutting off a damaged end and re-crimping a fitting, high-pressure hose should not be repaired.

Osha Requires High Pressure Hose Inspections
Federal Occupational Safety and Health Administration regulations require high-pressure hose inspections as prescribed below.

"All pressure hose and couplings shall be inspected at regular intervals appropriate to this service. The hose and couplings shall be tested with the hose extended, and using the ‘in-service maximum operating pressures." Any hose showing material deteriorations, signs of leakage, or weakness in its carcass or at the couplings, shall be withdrawn from service and repaired or discarded."

Testing the hose under pressure should be done only after a careful inspection. This testing procedure is incorporated as part of the general operating tests.

High Pressure Hose Failure Can Cause Serious Scalding
Keeping high-pressure hose in good condition is very important for safe high-pressure cleaner operation. Hose failure during hot water cleaning can result in serious scalding. Scalding is ranked by safety experts as a major danger connected with the use of high pressure hot water and steam cleaning equipment.

High Pressure Hose Damage
Most high-pressure hose failures are the result of damage to the hose from external stresses, particularly crushing or abrasion. In some cases, high pressure hose replacement is the largest cost of equipment operation over the life of the cleaner, even exceeding the cost of the original equipment purchase.


When cleaning tasks are performed, high pressure hose is often laid out across areas where vehicles pass and is consequently subject to severe crushing by heavy trucks and forklifts as well as automobiles. Hose failure due to crushing may be immediate or delayed. When high-pressure hose is crushed, the steel reinforcing wire is bent or broken. This weakens the hose’s ability to contain pressure and failure will eventually result. Crushing can be avoided by using good sense and care when laying out high-pressure hose. Instruct the operator to avoid extending hose across areas where vehicular traffic is likely to pass. Instruct the operator to not leave hose extended after cleaning is completed.

Damage to the cover of high pressure hose can also result in delayed hose failure. Cover abrasion exposes reinforcing wire to the elements and resulting rust or corrosion will lead to eventual hose failure. Caution the operator to not expose high pressure hose to sharp objects such as sharp metal edges or to conditions where cover damage is likely to occur.

Excessive Heat
Exposure to excessive heat can also cause hose deterioration. Always use combination steam and high-pressure hot water hose in cleaning situations where high temperatures are the rule. High pressure hose should never be operated simultaneously at maximum rated pressure and temperature. Most hot water cleaners are capable of producing output above maximum rated temperature of hydraulic hose normally used on many high-pressure cleaners. Use of combination steam and high-pressure hot water hose will prevent hose failures resulting from high temperatures encountered during normal equipment operations.

Other Factors Contributing To Premature Hose Failure
Kinking hose can lead to hose failure in much the same manner as crushing. A severe bend in the hose weakens reinforcing wire and continued stress in the same area will accelerate failure. Pulling equipment by the hose will cause damage to couplings or connections and may lead to the hose literally blowing off the machine.

Keep A Spare
If continuous cleaning system service is important, it is a good idea to keep a spare hose assembly on hand. This will allow the equipment to remain in safe operation even if a defective hose assembly is withdrawn from service.

Proper Handling And Storage
Handling and storing high-pressure hose properly can greatly reduce the possibility of hose damage. Proper coiling and storage should be demonstrated to the operator. A hose reel may be recommended as a way to reduce hose costs due to exterior hose damage. Hose can easily be wound up on the reel when not in use.

Line 6: Check Drive Belts.


With the machine stopped and cover open check the drive belt tension.

Important: Before checking belt tension be sure machine is unplugged. If machine cannot be unplugged for some reason and there is any type of remote start, skip this step.

As a general rule, ¼ to ½ inch deflection when pressure is applied on the belt is acceptable. If more deflection is apparent, suggest tightening the belt or belts. Check the belt or belts for wear and suggest replacing them if wear is noticeable.

Note: If a machine has a belt drive but no cover or belt shroud, inform the operator’s supervisor of the safety problem. Good safety practices and OSHA regulations prohibit exposed drive belts.

Line 7: Check Fuel Supplies.


Check the engine fuel. If a gasoline engine powers the cleaner, check the fuel and oil levels. If more fuel needs to be added, use an approved fuel container. Do not refuel the gasoline engine while the machine is in operation. According to safety regulations only properly rated fuel containers may be used for handling fuels. Although gas engine maintenance should be set up on a separate schedule it is a good idea to check the engine oil level at this time. Add or change engine oil as needed.

Check the burner fuel supply. Be sure there is an adequate amount of the proper fuel in the tank. If fuel is needed, add more fuel. Check the burner fuel filter bowl, if visible, for debris. Check the filter bowl for water as well. Add fuel if the fuel level is low. If the fuel is contaminated it may be necessary to clean and drain the fuel tank. Drawing water into the fuel pump can result in internal fuel pump rusting and consequent fuel pump failure.

Some full-featured cleaners have a safety device that prohibits burner firing when the fuel level in the tank is low. Fuel flow through the fuel pump is important because the fuel pump is self-lubricating and dry operation will cause the fuel pump to seize up. Check to see that the fuel source, tank, drum or jerrycan, is not contaminated with debris or water and make sure containers used for transferring are clean.

Line 8: Check For Scale Deposit.


Remove the discharge quick connect and check for scale deposit around the discharge fitting. If scaling is pronounced, that is if the inlet is turning white, descaling or some form of water pretreatment or both may be necessary. The extent of scale can be determined by testing for backpressure from the scale caused restriction of the coil. If pressure rises by more than 10% above normal operating pressure, descaling may be called for.

Scale Can Kill A Hot Water Cleaner
Scale and hard water can kill or cripple hot water cleaning systems. In most cases, and particularly where water is more than moderately hard, scale will build up inside a hot water machine’s heating coil.

As water is heated, impurities – including calcium, manganese, chloride and silicates – precipitate out of the water and form deposits, called scale, on the inside of the coil. Not only does scale restrict the flow of water through the coil, it is an excellent insulator and its buildup will significantly reduce the coil’s efficiency as a heat exchanger. The cleaner may seem to operate in a normal manner but the water will not reach previous temperatures. A loss in output temperature may result from scaling. If scale build-up is not controlled, coil replacement may be required. The thicker this deposit, the more serious the scale buildup problem.

Note: Scale buildup inside the coil may be thinker than the scale deposit in the outlet fitting.

Weapons In The War On Scale
There are a number of weapons which can be used in fighting scale, ranging from electronic devices through chemical softeners and as a last resort, acidizing, or flushing the heating coil and pressure hose with an inhibited acid solution. Cleaning chemicals can also contribute to and help prevent scaling.

In some cases the bulk of scale deposits will be made up of cleaning chemical deposits. In this case, very little of the scale will be the result of mineral deposits precipitating from hard water. Using a cleaning chemical that reduces this buildup goes a long way toward reducing the need for descaling procedures. A cleaning chemical formulation can include water softening agents which reduce calcium and silicate deposits. Proper care of equipment including use of scale reducing cleaning chemicals and a water softening or pre-treatment device may be the most economical approach to solving or controlling scale problems. In areas where hard water is a problem, distributors can enhance profits and satisfy customers by coming up with effective scale-fighting solutions. Many European-design hot water cleaners have come with a water-softening system as standard equipment. Often what appears to be a lime deposit may be a cleaning chemical residual deposit instead and will not require extensive descaling.

Line 9: Check For Sooting.


Check the heat exchanger for soot build-up. Do this by looking in the stack when the burner is not operating. Sooting is caused by carbon deposits from fuel that has not been completely burned. Generally these deposits are caused by delivery of insufficient air for proper combustion. Soot buildup can, like scale, insulate the coil and cause output water temperature to drop. Sooting may occur and a significant buildup accumulation even if there is no visible smoking when the burner is operating. On an oil-fired burner, sooting can usually be cured by adjusting the air bands (gun-type burner) or the air damper (European type burner) to increase the amount of air delivered. Do not over adjust too much air may be delivered, which may also result in improper combustion.

If a smoke testing kit is available, a sample should be taken after each air adjustment and air delivery adjusted until the lowest reading, preferably a one or two, is achieved. Although sooting is generally more of a problem with oil-fired burners gas-fired units can have sooting problems as well. Lack of adequate air supply is usually the problem. If the unit is installed in an enclosed space, adequate ventilation must be provided. As a rule of thumb, a burner needs 0.9 cubic foot of air for every 100 Btu produced. This means that a 195,000 Btu per hour burner would require 1755 cubic feet of air. If soot build-up appears excessive, desooting may be called for. Desooting usually involves removing the coil and washing it off. This can be a very dirty job and proper management of the wash water waste stream is important.

Start The Cleaner
Naturally, to determine if a high pressure cleaner is working properly, you will have to start it up and make sure it is producing the desired pressure, flow and temperature output. The previous items in the checklist have constituted a pre-operation inspection of the equipment.

Important: If there are any questions about equipment hook-up or operations, consult the owner’s manual before proceeding.

Put the chemical line in the chemical container. Make sure the end of the line is fully submerged. It is best to use at least a five-gallon chemical container for prolonged washing. Make sure you have at least 2 to 3 gallons of chemical in the container. Make certain the chemical valve is open so that any air trapped in the line can be purged once the cleaner is started.

Important: Before starting the cleaner, make certain the immediate area where you are operating the equipment is clear of any other persons. Make sure the lance is not pointing at any person or at any part of your body. Make sure you are in full control of the lance before turning the cleaner on.

Safety Warning: Make certain proper personal protective equipment is used at all times when the cleaner is in use. Whenever washing is in progress the operator and other workers in the washing area should wear safety glasses and any other personal protective equipment dictated by the type of chemical in use. Certain job sites or industrial locations will have specific requirements for personal protective equipment such as hard hats. Earplugs are recommended in any high noise environment and for use when operating gas engine cleaners.

Electric Motor Powered Equipment


Plug in the power cord of check to see that cord is plugged in and properly grounded. Do not operate equipment without a ground or with a suspicious ground. (Any new, 115V equipment should be equipped with a ground fault circuit interrupter).

If the circuit breaker trips, check to see if there is other equipment on the line. Make sure the circuit breaker is rated for 20 amps or more if you are using a 115 V cleaner. Turn the pump switch to on or turn the rotary switch to the cold-water position. Always start equipment with the gun open. Always start the equipment on low pressure if possible. If the equipment does not allow variable pressure adjustment, check the pressure nozzle for obstruction before starting the equipment. Once any air from the chemical line has been purged from the system, adjust the chemical valve to the desired position.

Turn on the burner switch or turn a rotary switch to the hot water position. Turn the temperature control to an appropriate setting. (One of the dangers presented by hot water cleaners is the danger of scalding. The lower the water temperature, the more this danger is reduced. Generally a temperature around 140 degrees Fahrenheit is adequate for most washing applications. A higher temperature should not be used unless needed for heavy cleaning or disinfection). Let the machine heat up. If the machine has a trigger gun, keep the trigger depressed for continuous burner action. The machine should be fully heated and have adequate chemical flow after about two minutes.

Gasoline Engine Powered Equipment


Most gasoline engine powered cleaners’ start about the same way. Check the owner’s manual for any procedures specific to the type of engine on the equipment you are using. Always check the oil first. Add oil if needed. While looking at the dipstick, check the color of the oil. If the oil is very dark, an oil change is called for.

Next, make sure that the fuel tank is full of the proper fuel. If the engine is a Honda or Wisconsin Robin, check to see that the gas valve is turned on. This is not necessary with a Briggs and Stratton engine. If you are not sure about the gas valve, try starting the engine first. If it will not start, consult the owner’s manual to determine the location of the gas valve.

Some engines are equipped with a primer bulb on the gas line. This is used to pump gas to prime the carburetor. Generally squeezing the bulb two and one-half times is all that is needed to prime the carburetor. Turn the choke on. Squeeze the trigger gun before starting to reduce the load on the engine. A second person can hold the trigger gun open. Always start the equipment on low pressure if possible. If the equipment does not allow variable pressure adjustment, check the pressure nozzle for obstruction before starting the equipment. Start the engine using either the manual recoil starter or the electric starter depending on how the engine is equipped.

An engine with recoil starter should crank within five pulls. When using the recoil starter, do not completely release the handle and allow it to snap back to the engine, instead retain control of the starter. When the engine starts, turn the choke off and if the engine begins to sputter or die, turn the choke back on, about half way, until the engine warms up. Once the engine is warm, return the choke to off position or the engine will begin emitting black smoke, indicating that it is running on too rich a fuel mixture.

Once the engine is running smoothly, advance the throttle to full speed to get the pump’s rated output. Once any air from the chemical line has been purged from the system, adjust the chemical valve to the desired position. On many hot water cleaners, the water heater burner will not fire unless the pump is running at full output capacity. This is because the burner is controlled by a safety device, which will not allow burner operation unless either full flow or pressure is being generated by the pump. Therefore, the unit will not heat up while the engine is running at idle. Turn on the burner switch.

Turn the temperature control to an appropriate setting. (One of the dangers presented by hot water cleaners is the danger of scalding. The lower the water temperature, the more this danger is reduced. Generally a temperature around 140 degrees Fahrenheit is adequate for most washing applications. A higher temperature should not be used unless needed for heavy cleaning or disinfection). Let the machine heat up. If the machine has a trigger gun, keep the trigger depressed for continuous burner action. The machine should be fully heated and have adequate chemical flow after about two minutes.

Operating Gas-Fired Cleaners


To operate a gas-fired hot water cleaner, first turn on the pump unit by setting the pumping unit switch to the "on" position. Start the equipment with the gun open. Turn the burner switch to on, keeping the trigger depressed so that water is flowing through the system. The burner will not ignite immediately. Within five to 30 seconds the burner will come on. Keep the trigger depressed for as long as hot water is needed. Do not stop and start washing operations frequently as this will disrupt burner operation.

Because of the nature of the fuel and the manner in which the fuel is supplied to the combustion area, gas burners do not respond to a call for flame from burner controls as rapidly as do oil burners. With any gas burner, there is a delay before flame is established. An oil-fired burner, however, will respond almost instantaneously with fie in the combustion area to a demand for heat from burner controls.

Consequently gas-fired hot water equipment calls for a different operation procedure than does oil-fired equipment. Once a gas burner is turned on at the burner switch, the trigger gun should be kept open for as long a period of washing as possible. The reason: each time the gas burner shuts off; it takes from several seconds to half a minute for the burner to restart.

Since shutting water flow off at the gun causes the flow switch or other burner control to cut off the burner, each time the trigger is released and depressed again, the burner shuts down completely and then begins a fairly lengthy restarting cycle. For natural-draft burners, restarting will take a few seconds to allow the gas valve to react and a flow of gas to reach the combustion area. It also takes a few seconds for shutdown to occur because gas already in the line must be burned. If a forced-draft burner with an automatic purge cycle is used, the delay before resumed burner firing may be more than 30 seconds overall.

Releasing and re-depressing the trigger several times in even moderately quick succession will first break, and then reopen the burner control circuit more rapidly than the burner will respond and the burner will not fire. Operators using gas-fired equipment should be taught to intersperse relatively long periods of washing with relatively long periods of shutdown to allow sufficient time for the burner to respond to demands for heat.

The Automatic Ignition Gas Burner
The gas burner with automatic ignition does not have a pilot light. When burner action is called for an ignition spark is provided and the pilot valve is opened allowing gas flow to the pilot orifice. The ignition arc ignites the gas escaping from the pilot orifice. If a pilot flame is established the pilot light’s heat is sensed and the main gas valve opens. If no pilot flame is established, the ignition arc will continue for 20 to 30 seconds and the system will shut down. Generally the entire system will have to be turned off to try to restart the pilot because of a safety lock-out intended to prevent various gas hazards. You may begin applying chemical to confirm chemical delivery while the unit is heating.

Line 10: Check For Fluid Leaks.


You can make this check while the cleaner is heating up. Inspect the cleaner’s fluid handling system for fluid leaks. Check all accessible fittings and connections. If necessary, open the machine cover and check for leaks at all locations. The machine should be started and checked in a dry area so that fluid leaks will be more readily apparent.

If water is running out from under the float tank, check to see if the float is filled with water, holding the float down and allowing the tank to overfill. Drain and seal the float so that the condition will not recur. If the float appears damaged, the float or float valve assembly may need to be repaired or replaced. When checking the float tank, look for debris in the tank. If debris is present, the tank should be cleaned. Make sure that the float tank cover is in place and in tact. A lost or damaged float tank cover can permit entry of debris into the system and failure may result. If fluid leaks are apparent
take the necessary steps to remedy them.

Line 11: Check System Pressure & Unloader Operation.


If the unit has a pressure gauge, check to see that output pressure is within 5% to 10% of rated system pressure. If there is no pressure gauge on the unit and pressure appears to be either lower or higher than normal for the unit, a pressure gauge attached to quick connects can be installed at the water outlet and a pressure reading taken. If pressure appears normal, there is probably no need to make a pressure reading.

Check the fluid system and pump for vibration or chattering. This may indicate an air leak into the system or a water-starved pump. Check for air leaks. Make sure no air is being drawn through the chemical line. Make sure enough water is being supplied to the system. If there is an air leak, the system will need to be purged of air after the problem is corrected. Inlet water, which is too hot, can also cause cavitations or chattering as can a stuck check valve.

If pressure is too high or too low and pump action is normal, an unloader or pressure regulator adjustment may be called for. However, check the nozzle first to determine if nozzle wear is the reason for the pressure loss. Over a period of time, water will erode even the hardest stainless steel orifice and a loss of pressure will result. Before adjusting the unloader, check its action. Open and close the trigger gun several times. If there is a pressure gauge on the unit or if you are using a gauge on a quick connect, check to see that there is a not an excessive pressure spike when the trigger is released. If the unit has a flow-actuated unloader and unloader cycling is noted, then either system flow is not at the optimum level or the wrong orifice is installed in the unloader.

Pressure Unloader Adjustment


Pressure unloaders must be adjusted with the system operating and the trigger depressed so that water is flowing through the spray nozzle. The initial adjusting bolt position should be loose or screwed away from the body and the very little tension on the spring. Release the trigger to see if the unloader is going to work at all. Depress the trigger, allowing the system to develop operating pressure at the unloader adjustment. Note the pressure gauge reading.

Depress the trigger and tighten the adjusting bolt about one turn. Repeat until the desired pressure is reached. Use the gauge to monitor the system pressure rise with each adjustment. All adjustments must be made with water flowing and pressure in the system. Release the trigger only to check spike pressure. This adjustment procedure is exactly the opposite of the procedure for adjusting the flow unloader. When the desired pressure is reached, tighten the lock nut to make the adjustment permanent.

Flow Unloader Adjustment
Flow unloader adjustments must be made with the cleaner operating and the trigger gun released. The flow unloader allows the system to develop the lowest pressure when the adjusting bolt is screwed all the way into the valve body. When the trigger is first released, monitor the pressure gauge to make sure the unloader valve is operating at all. If pressure continues to rise rapidly, open the gun and shut off the cleaner. Start the flow unloader adjustment procedure with the adjusting bolt screwed all the way into the valve body and the system developing minimum pressure.

To check pressure when adjusting the unloader, simply open the trigger gun. Allow full system pressure at that adjustment to be achieved. The unloader should be adjusted gradually until the desired pressure is achieved. Turn the adjusting bolt one turn, then open the trigger gun and wait till even pressure is achieved before checking the pressure gauge.

When opening the gun for a pressure check, allow a moment for system pressure to stabilize before noting the pressure. If pressure is not high enough, release the trigger and turn the adjusting bolt again. Squeeze the trigger and check the pressure again. If more pressure is desired, repeat this step, checking pressure and spike each time. When finished, tighten the lock nut to prevent loosening and make the adjustment permanent. If adjusting the unloader does not bring the system up to pressure, a pump rebuild may be indicated. See the section on fluid system problems for diagnostic procedures to determine if a rebuild is called for. Usually low-pressure problems will be caused by something other than packing wear unless the cleaner has been in heavy service for a year or more.

Line 12: Check For Proper Chemical Delivery.


With the system operating and the chemical line in the chemical container, open the chemical valve and see if chemical flow results. If necessary, you may adjust the flow by turning the metering valve knob until a reasonable amount of chemical for the application is being delivered. If the system has a downstream injector you will need to switch to low pressure to deliver chemical. In all cases, make sure that the chemical line is fully submerged. Check the chemical strainer for clogging. If there is no strainer or foot valve on the chemical line, a strainer should be installed.

Line 13: Check The Trigger Gun.


Inspect the trigger gun for damage or leaking. If trigger gun leaks at the back, suggest replacement of the o-ring at the pin or piston assembly. Make sure the safety lock is in place and works. Check to see that no attempts to defeat the trigger gun with wire have been made. Check the quick coupling. Check to see that trigger gun operation is smooth and water flow is regular. If damage or leaking is apparent the trigger gun should be repaired or replaced.

If the trigger gun does not shut off the flow or if the trigger sticks a great deal, the equipment should be removed from service until the problem is corrected. The quickest way is to replace the trigger gun with a spare. If no spare is available, refer to the section on trigger gun service.



Gun leaking usually occurs only in one of two different spots. If water is leaking through the spray nozzle when the gun is shut off the problem is likely to be a bad valve ball or seat. If water is leaking out of the plastic handles, a bad o-ring on the control pin or piston rod is likely to be the problem.

If the gun is leaking, the first step is to remove the plug on the back of the valve body that retains the valve spring. This plug is fitted with an o-ring at the base of the cap. If the o-ring shows damage or wear, it should be replaced. Lubricate the new o-ring and slip it carefully over the threaded plug, taking care not to damage the o-ring.
Note: Leaking past the valve ball and out of the spray nozzle when the gun is shut off will cause the unloader to cycle in and out of bypass. On guns with a total shut off feature, leaking past the valve ball will cause the machine to cycle, starting up and stopping even without an operator present.

Weep Guns


Some trigger guns may be defined as weep guns. These guns allow a small amount of water to escape or weep by the seat. Weep guns are generally used in car washes or in cold climates since they can help prevent freezing by allowing for some water flow. The weep feature is determined by the valve seat. Some manufactures will drill a small hole through the surface around the port opening. Other manufacturers will simply notch the actual seating surface so that the valve ball does not make a positive seal against the valve seat.

Some weep types seats are reversible. One side will be notched, allowing weeping. The other side, without a notch, will allow for a complete seal. On the reversible type the gun may be used either as a weep gun or a regular gun. If the valve seat is removed from a reversible weep gun, make certain it is replaced in the same manner in which it was originally assembled unless a change is intended. Leaking generally does not occur around the inlet and outlet fittings. These fittings are hard to remove and should not be disturbed unless absolutely necessary. If the fittings must be removed, clean the threads and tape with Teflon tape before reassembly.

Service Hint: Some newer guns have unitized repair kits including the seat, valve ball, retainer and plug cap assembled together. These kits are simply inserted as a single unit into the rear port.

Note: Leaking at the trigger gun’s inlet or outlet fittings will occur after an inexperienced person has tried to remove the discharge hose or lance. Inexperienced personnel are likely to hold the trigger gun and try to screw off the discharge fitting. This will loosen the internal gun connection. When removing a discharge hose or spray lance, the trigger gun inlet or outlet fitting must be securely held while the lance or hose is removed. This process requires two wrenches (one to hold and one to turn) but guarantees you will not make the fitting leak.

Line 14: Check The Spray Lance.


Check to see that the lance is not bent or damaged. If hot water, an insulated lance should be used. If the lance does not have an insulated grip, a new grip should be installed or the lance replaced with a lance with an insulated grip. This is essential to prevent injury to the operator from gripping a hot lance.

Check to see that the lance is appropriate to the application. For general use, the lance should be 36 inches long or longer to reduce the possibility of the operator accidently getting sprayed. Shorter lances may be used for some applications and very long may be used for some applications and very long lances may be called for in truck cleaning or other instances where extended reach is called for.

If variable pressure lance is used, check to see that it operates properly by adjusting it to low pressure and back again several times. If the lance is severely bent or damaged or if variable pressure lance operation is improper the lance should be replaced or repaired. The operator should be cautioned to take proper care of the lance to prevent further damage from occurring.

Line 15: Check The Spray Nozzle.


Inspect the nozzle for wear or damage, check for obstructions; if the nozzle is clogged, the spray pattern will be distorted. Do not inspect the nozzle unless machine is off. Check to see if the spray angle is proper for the application. If there is any question, check your nozzle chart to make sure the nozzle is the right size for the equipment.

Sizing Spray Nozzles


Spray nozzles are sized to produce the equipment’s rated flow and pressure. Spray nozzle sizing for most pressure and flow ratings are included in the spray nozzle chart. This chart is easy to read. To find the correct spray nozzle size, look up the pounds per square inch (psi) rating of the machine and run your finger down till you get to the closest gallons per minute (gpm).

If you do not have the exact size when replacing a spray nozzle, use the next size larger rather than smaller because moving water through the smaller orifice will require more effort from the electric motor, and consequently more amperage. The increased draw can trip a circuit breaker. This increased draw can trip a circuit breaker. This can be a particularly annoying problem with 115V hot water machines, which usually operate on 20 amp breakers and normally draw 17 to 19 amps for operation.

Spray Angle


Spray jet angle also helps determine the cleaning ability of a specific flow at a specific pressure. The angle refers to the theoretical spread of the stream of water coming from the spray nozzle. Spray nozzles used in pressure cleaning generally range from zero degrees to 65 degrees in theoretical spray pattern spread. The narrower the stream of water coming out of the spray nozzle the more impact, but the less coverage and the longer it might take to clean a specific area.

How Far?
How far the spray nozzle is from the surface being cleaned makes a big difference in water impact. The greater this distance, the less impact water will have. However, the greater distance increases the amount of area covered by the spray. The operator can easily adjust the spraying distance to suit different types of soil and perform his job most efficiently.

When water is sprayed into the atmosphere from the spray nozzle it immediately begins losing speed, and consequently force, due to air friction and other factors. Holding the spray nozzle very close to the surface will give more impact on hard-to-clean areas. Holding the spray nozzle four or five inches away will be adequate for most moderate soils. (The wider the spray patter, the closer the spray nozzle will have to be held to the surface to get the same performance as a spray nozzle with the tight, 15-degree spray pattern.

Nozzle Wear Characteristics


Wear on the nozzle will eventually result in pressure loss as the flow of water slowly enlarges the orifice. In a fan spray type pattern, the most common in the industry, a narrowing of the spray pattern will also be noticed. Because of the variety of variables, such as type of chemicals used, hardness of water, and velocity of the spray to name three, engineers are reluctant to give estimates on nozzle life. Additionally, the amount of wear permissible varies according to application and user preference. That is, will a slight but steadily increasing pressure loss over time make enough of a difference tonecessitate a nozzle change and at what point in the wear pattern should this change be made?

The answer is up to the operator. However, a nozzle change, rather than an unloader adjustment, is the first action to take to correct such a pressure loss. Nozzles are precision-machined tools. They should be handled with relative care and properly stored.

Check For Clogging
Distorted or broken spray patterns, sometimes coupled with low or erratic pressure are signs of nozzle clogging. A clogged nozzle may be mistakenly diagnosed as a pump or unloader problem.

Debris From The Water Supply


Clogging from debris passing through the system from the water supply is more rare than from other causes since there are so many intervening areas where such debris can lodge. Another debris-related problem, such as a stuck check valve, is likely to occur before nozzle clogging results from debris entering the system at the water supply.

Debris in the water supply is most often picked up when the discharge hose is disconnected from the cleaner for storage. The hose is usually dropped to the ground, where it is likely to pick up debris, before it is coiled for storage. Debris may also originate inside the machine. Such debris results from deterioration of seals or other polymers or from internal rust or corrosion as well.

Preventing Clogging
The best way to prevent nozzle clogging from internal debris is to always start the system either without a nozzle or with a variable pressure lance set to the lowest possible pressure. Debris, which could clog the high-pressure nozzle, may be flushed out through the end of the lance or through the low-pressure nozzle’s substantially larger orifice.

Remove Nozzle For Cleaning
If a spray nozzle is clogged, it is best to remove it from the lance before cleaning it. Cleaning it from the outlet end will simply push the debris back into the system and reclogging may result. Removal of the spray nozzle while it is still clogged will usually guarantee that the trapped debris is also removed. Once the nozzle is removed from the system, a probe of suitable size may be used to push the debris out of the nozzle. This should be done from the outside in. Any debris remaining in the inlet side of the nozzle should be cleaned out. If lime or chemical scale is present in the inlet side, the nozzle may be soaked in descaling solution or replaced. Scale will form on the inlet side of the nozzle and may create problems elsewhere in the system long before the orifice is restricted by scale. Before replacing a cleared nozzle, flush the system thoroughly with the nozzle removed to clear any additional debris from the system.

Line 16: Check For Proper Burner Operation.


With the equipment operating, and the thermostat (if applicable) set to its highest setting below steam mode, see if the equipment comes up to optimum operating temperature. This should happen in a couple of minutes and will be indicated by burner shutoff. Once any unburned fuel has been burned from the combustion chamber, smoking should stop completely. If smoking continues, a burner adjustment is indicated.

Open and close the trigger gun several times to see that the burner shuts off and restarts properly and promptly. Remember that with a gas-fired burner there will be some delay in shutdown or restart so this procedure should be done much more slowly than with an oil-fired system. If burner problems are encountered, refer to the appropriate section on burner adjustment or burner diagnosis. However, here is a brief discussion of some problems, which may be discovered.

If excessive smoking continues more that 30 seconds to a minute after start-up there is probably unburned fuel in the combustion chamber and this will need to be either drained or burned out. Moderate smoking is probably caused by an improper air adjustment. If the burner does not shut off when the trigger gun is closed there is probably a boiler control problem and the unit should be removed from service until the problem is isolated and corrected.

If the oil burner does not restart properly and promptly there is probably a fuel delivery problem, although air delivery or ignition difficulties may also cause this problem. If the burner does not start at all, begin diagnostic procedures and repair the system. If burner operation is less than optimal, the fuel, air and ignition systems should be checked and adjusted until the burner operates properly.

Shut Down The Equipment


Cool off the cleaner by allowing it to operate for about two minutes in cold-water mode with the trigger depressed before turning off the pumping unit. Do this with the chemical valve closed in order to flush any remaining chemical out of the system. Turn off the pumping unit. Squeeze the trigger once or twice to allow water under pressure in the discharge line to escape.

Coil the high pressure hose and store it either on the cleaner’s handle (often designed for hose storage) or on an appropriate hook or rack. If the cleaner is equipped with a hose reel, make sure the hose is properly coiled back onto the reel. Do not leave hose extended when the cleaner is not in use, this is an invitation to hose damage.

If the cleaner is to be moved, disconnect the garden hose if the cleaner is hooked up to an outside water source. Store the garden hose properly. If the cleaner is electrically powered, unplug and coil the power cord. (It is generally a good idea to unplug any cleaner that will not be used again immediately). If cold weather (32 degrees Fahrenheit or below) is expected, the cleaner should be protected from freezing. The best freeze protection is to move the cleaner into a heated building. If no heated space for storage of the cleaner during cold weather is available, the unit may be filled with an anti-freeze solution.

Line 17: Check For Adequate And Proper Chemicals.

Make sure there is an adequate supply of the proper chemicals for the application. If the chemical supply is inadequate, more chemical should probably be ordered. If you find harsh or caustic chemicals present, make sure they are being delivered by downstream rather than upstream injection, if no downstream injector is provided with the system, one should be installed or the harsh chemicals properly disposed of. If dangerous chemicals are found, they should be properly disposed of.

Keep Equipment Looking Good

There is no reason why cleaning equipment should not be kept in good appearance. This is simply a matter of cleaning the unit on a regular basis. A clean machine is easier to maintain and operate and will generally last longer than a machine that is not cared for. To clean a unit, wipe it down with Windex and paper towels. When machine is clean, spray the equipment’s protective cover with a thin film of WD-40 to keep it looking good. If equipment is extremely dirty or appears to have been abused, report the situation to the appropriate supervisor for action.

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