Aqua-Hot AHE-250-D03 error code SMOKE OR SOOT AT EXHAUST
Visible black smoke or accumulating soot at the exhaust pipe indicates incomplete combustion - downstream effect is photo-eye contamination and 'Burner Failed to Ignite' fault recurrence.
What to check, and in what order, is in the app. The flow Aqua-Hot — Diesel Burner Test 4 (Ignition Coil) and Downstream Diagnostics 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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- Aqua-Hot 200-Series 250P/250D Service ManualAqua-Hot
- Aqua-Hot Heating Systems Service Manuals — aquahot.com
- Aqua-Hot Tech Support 800-685-4298 (Fort Lupton, CO)
- AquaHot 250 D03 Diesel Hydronic Technician Service Diagnostic Reference (rv-tech-resources/53-aquahot-250-hydronic/AquaHot_250_D03_Diesel_Hydronic_Technician_Service_Diagnostic_Reference.md)
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