Troubleshooting A Hot Water Pressure Washer – Burner Not Firing Properly

What We Cover: Burner Is Not Firing Properly

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.

  1. Proper Air Delivery
  2. Electrode Spark
  3. Delivery of Fuel

Issue #1 → Proper Air Delivery

Cause 1: Too Much Air at Combustion

A proper amount of air is needed to meet the oxygen requirement for proper combustion.

  1. 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.Proper Air Delivery Part 1
  2. Excessive white smoke is not normal and indicates there is too much air at combustion.
  3. 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. Proper Air Delivery Part 2

Cause 2: Broken or Loose Belt

A broken or loose belt on the fan affects the airflow, and also can affect fuel delivery and spark.

  1. This belt should be inspected first to make sure it is working properly.
  2. To access the fan belt, remove the inspection plate at the back of the machine just above the fuel tank.
  3. You can also check the belt by looking inside the machine directly below the water pump. Broken or Loose Belt Part 1
  4. 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. Broken or Loose Belt Part 2

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.

Issue #2 → Electrode Spark

Cause: Incorrect Gapping of Electrodes, Cracked Electrodes, or Bad EMF Ignition Coil

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.

  1. The main problems that could impact a proper ignition are incorrect gapping of electrodes, and cracked electrodes.
  2. 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. Electrode Spark
  3. Contact a qualified Mi‑T‑M Service Center for further assistance.

Issue #3 → Delivery of Fuel

Cause: Plugged Nozzle, Plugged Fuel Filter, or a Bad Fuel Pump

Fuel is atomized and injected into the combustion chamber by a spray nozzle.

  1. The main causes of improper fuel delivery could be a plugged nozzle or a plugged fuel filter.
  2. If replacement of these hot water pressure washer parts does not solve the problem, then you may have a bad fuel pump. Delivery of Fuel
  3. Contact a qualified Mi‑T‑M Service Center for assistance with the fuel pump.

Need Help?

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.