Complete repair guide for the Leisure Travel Vans Unity – Diesel Heater Glow Plug & Fuel Pump Service. Follow these steps to diagnose and fix the issue yourself.
Parts & Tools You’ll Need
- Webasto / Espar ceramic glow plug
- Diesel heater fuel dosing pump (12V)
- Inline diesel fuel filter
- Diesel heater LCD control panel
- Combustion chamber blower motor
- Intake & exhaust silencer kit
- Diesel fuel line silicone tubing (4mm)
- Digital multimeter (auto-ranging)
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Step-by-Step Repair Guide
Step 1: Diagnose Heater Failure and Safety
Start by connecting your digital multimeter to the glow plug terminals to test for proper voltage delivery—you should see approximately 12V when the heater ignition is activated. If voltage is absent or the heater won’t ignite, you’ve likely identified a faulty glow plug or fuel pump that requires replacement.
Step 2: Disconnect Battery and Remove Panel
Turn off your Leisure Travel Vans Unity’s main battery disconnect switch and wait 10 minutes for all systems to discharge safely. Carefully remove the diesel heater LCD control panel by unclipping the surrounding trim pieces and disconnecting the wiring harness from the back.
Step 3: Replace Glow Plug and Pump
Locate the ceramic glow plug on the combustion chamber and unscrew it counterclockwise using the appropriate wrench, then screw in your new Webasto or Espar glow plug by hand first before tightening. Access the 12V diesel heater fuel dosing pump mounted near the fuel line connection, disconnect its electrical connector and fuel lines, then install the replacement pump using new silicone tubing and secure all connections with hose clamps.
Step 4: Service Fuel System Components
Replace your inline diesel fuel filter by closing the fuel supply valve, unclipping the old filter housing, and inserting a new filter cartridge into the clean housing. Inspect all 4mm diesel fuel line silicone tubing for cracks or hardening, and replace any sections that show deterioration to prevent air leaks or fuel leakage.
Step 5: Inspect Blower and Silencers
Check your combustion chamber blower motor for debris accumulation and clean the fan blades gently with a soft brush to restore proper airflow. Examine both the intake and exhaust silencers for carbon buildup or damage, and replace them if you notice restrictions or corrosion that would impede heater performance.
Step 6: Reinstall Control Panel Connections
Reconnect the diesel heater LCD control panel wiring harness, ensuring all connectors click firmly into place, then secure the panel back into the surrounding trim by snapping all clip points. Double-check that the glow plug and fuel pump electrical connections are fully seated in their harnesses before proceeding to testing.
Step 7: Test System and Verify Operation
Reconnect your main battery disconnect switch and power on the diesel heater system, observing the LCD control panel for proper initialization and display function. Run the heater for 5 minutes while monitoring combustion chamber temperature and listening for normal ignition sequence, then use your multimeter to confirm the glow plug receives consistent 12V voltage during operation and the fuel dosing pump cycles properly.
Recommended Parts
| Part | Link |
|---|---|
| Webasto / Espar ceramic glow plug | View on Amazon |
| Diesel heater fuel dosing pump (12V) | View on Amazon |
| Inline diesel fuel filter | View on Amazon |
| Diesel heater LCD control panel | View on Amazon |
| Combustion chamber blower motor | View on Amazon |
| Intake & exhaust silencer kit | View on Amazon |
| Diesel fuel line silicone tubing (4mm) | View on Amazon |
| Digital multimeter (auto-ranging) | View on Amazon |