Troubleshooting a Hot Water Pressure Washer: Part 1

Built from the highest quality components available, Mi‑T‑M hot water pressure washers are the best in the industry. With proper maintenance, these pressure washers will perform for many years. A problem with your pressure washer may be caused by a hot water pressure washer part that can easily be replaced. This video will show you what to do when the burner will not fire properly.

There are three important functions that must take place for a hot water pressure washer to perform correctly.

  • Delivery of the proper amount of air
  • Electrode Spark
  • And Delivery of fuel

A proper amount of air is needed to meet the oxygen requirement for proper combustion. All Mi‑T‑M hot water pressure washers are tested for this prior to shipping. To determine if your washer is getting the proper amount of air, check for white smoke at burner ignition. A slight puff of white smoke is normal.

Excessive white smoke is not normal and indicates there is too much air at combustion. Not enough air causes black smoke. Do not operate your hot water pressure washer if black smoke is present. The black smoke will not only soot up the water coil, but can cause temperature loss at the trigger gun.

A broken or loose belt on the fan affects the airflow, and also can affect fuel delivery and spark. This belt should be inspected first to make sure it is working properly. To access the fan belt, remove the inspection plate at the back of the machine just above the fuel tank. You can also check the belt by looking inside the machine directly below the water pump. If the belt is in place and working properly, an adjustment of the control lever may need to be made. The control lever regulates the amount of air delivered, which determines the quality of the burn. If you need to adjust the direction of the airflow, contact a qualified Mi‑T‑M Service Center or the Mi‑T‑M Technical Services department for assistance.

The ignition spark is distributed by two electrodes in the firing chamber of the hot water boiler. These electrodes receive voltage from the ignition coil which is part of the Mi‑T‑M patented E-M-F system. The main problems that could impact a proper ignition are incorrect gapping of electrodes, and cracked electrodes. If these parts are working properly and you still do not have a spark, it could be the result of a bad E-M-F ignition coil. Contact a qualified Mi‑T‑M Service Center for further assistance.

Fuel is atomized and injected into the combustion chamber by a spray nozzle. The main causes of improper fuel delivery could be a plugged nozzle or a plugged fuel filter. If replacement of these hot water pressure washer parts does not solve the problem, then you may have a bad fuel pump. Contact a qualified Mi‑T‑M Service Center for assistance with the fuel pump.

As with all equipment, preventive maintenance of your hot water pressure washer will help to avoid many of these problems. Please take the time to review the preventive maintenance video on this website. If you do experience burner issues with your Mi‑T‑M hot water pressure washer, contact an authorized Mi‑T‑M Service Center or the Mi‑T‑M Technical Services department to receive professional help to get you back up and running.