Diesel heater service

Always start by turning off the heater correctly and letting it cool down completely. Then disconnect the power to the system so there is no risk of accidental startup during service.

1. Turn off the heater on the controller
2. Wait until the cool-down cycle is finished
3. Disconnect main power or fuse
4. Check that the heater is completely cold

Remove the housing and the covers that provide access to the heater's main components. Work carefully and keep screws and small parts in the order they were removed.

• Glow plug
• Screen or glow mesh if the model uses one
• Burner and combustion chamber
• Gaskets
• Fan and airways

Dust, soot and dirt in the fan and air channels can reduce airflow and affect combustion. Clean the area carefully without damaging sensitive components.

• Clean the fan wheel and fan housing
• Remove dust and soot from airways
• Check that nothing rubs or is stuck

The glow plug is one of the most important wear parts in a diesel heater. If it is worn, weak or heavily covered in soot, the heater may have trouble starting and burning cleanly.

• Check for heavy soot deposits
• Look for discoloration or obvious wear
• Replace the screen or glow mesh if clogged or burnt
• Replace the glow plug if worn or causing poor startup

The burner and combustion chamber often collect soot and carbon, especially if the heater has been running a lot on low output. Clean the parts so combustion can once again be stable and clean.

1. Remove loose soot and deposits
2. Check if the parts are cracked or burnt through
3. Replace the burner if it is clearly worn or damaged

Gaskets must seal tightly around the hot parts and the airways. If they have become hard, brittle or distorted, they should be replaced during service.

• Check gaskets around the glow plug and burner
• Look for leaks, distortion or cracks
• Replace worn gaskets before reassembly

The fuel system must be tight and free of dirt. Even small leaks or poor fuel delivery can cause startup problems and unstable running.

• Check hoses and connections for leaks
• Inspect the filter for dirt or old diesel
• Check that the pump is mounted correctly and firmly
• Use clean diesel (GTL) if possible for cleaner combustion

When the parts have been cleaned and any wear parts replaced, the heater is reassembled in the correct order. Then reconnect power and fuel and test the heater during startup.

1. Refit all parts correctly
2. Check that plugs, screws and joints are positioned correctly
3. Reconnect power and fuel
4. Start the heater and let it run through a cycle

Watch especially for:

• Whether there is abnormal smoke
• Whether there is any diesel or exhaust smell
• Whether the heater starts cleanly and runs steadily
• Whether the heat output is as it should be

• Run the heater at full output for 10-15 minutes from time to time
• Avoid only using low output for long periods
• Use clean diesel (GTL) if possible
• Service the heater at least once a year
• React early if startup or heat output changes