Truma VarioHeat error code W 28 H
Window above the exhaust cowl is open (window switch): the CP Plus inhibits the heater while a window near the roof/wall cowl is open, to keep exhaust out of the cabin.
What to check, and in what order, is in the app. The flow Truma: Error Code on Control Panel walks this code step by step with the pass/fail measurements, wiring schematics and procedures that go with it, and it works offline in the bay.
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- Common VarioHeat Error Codes (Truma tech tip)Truma
- CP Plus VarioHeat Operating Instructions troubleshooting chartTruma / ManualsLib
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