Unit Won’t Ignite
Check 12V supply voltage at the unit first — the Combi’s control board is sensitive to low voltage and will fault out well before the battery is actually “dead.” After that, check LP supply pressure and that the exhau...
Owner guide
Truma Combi Furnace & Water Heater Troubleshooting Guide
Combines space heating and water heating in one unit — increasingly common in van builds, and not well documented outside Europe. Here’s what to check. Check 12V supply voltage at the unit first — the Combi’s control boa...
Active corridor: Montana · Wyoming · Idaho · Washington — case-by-case beyond.
Field notes
Combines space heating and water heating in one unit — increasingly common in van builds, and not well documented outside Europe. Here’s what to check. Check 12V supply voltage at the unit first — the Combi’s control board is sensitive to low voltage and will fault out well before the battery is actually “dead.” After that, check LP supply pressure and that the exhaust/intake vent isn’t obstructed — the unit’s airflow sensor will block ignition if it detects restricted venting.
Heats Water but Not Air, or Vice Versa
The Combi runs both functions off one burner but controls them independently through the digital control panel — check that both zones are actually switched on in the panel settings before assuming a hardware fault. A...
Error Codes on the Digital Panel
The Combi’s control panel displays a numeric fault code rather than a description. Note the exact code before resetting power — it’s the single most useful piece of information for a technician diagnosing it remotely ...
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Water Heater TroubleshootingVan Build Electrical TroubleshootingCustom Van & Skoolie BuildsBack to Field Guide
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Pricing teaser
Trip fee $75 within 30 miles, then $1.50/mi. Labor ~$150/hr (1-hour minimum, billed in 30-minute increments). Diagnostic $150 applied toward repair if you proceed.
Active corridor: Montana · Wyoming · Idaho · Washington — case-by-case beyond. Credentials (text): Victron Professional Certified Installer · weBoost Authorized Installer · Peplink Certified Associate · Dometic Professional Certified.