Lochinvar error codes
The complete list of Lochinvar fault codes shown on the display, each with what it means and the page that explains how it is diagnosed and fixed.
Lochinvar heating appliances display 20 documented error codes. Each code below opens its own page with the official meaning, the documented causes, the safety assessment and the parts involved.
All Lochinvar Error Codes
20 codes, each with its own page. Click a code to open the meaning, the documented causes and the repair.
What Fails Most Often on Lochinvar
Grouped from the official meaning of each of the 20 codes above — not from opinion. The number is how many different fault codes point at that component.
| Component | Codes | Examples |
|---|---|---|
| Control Board | 6 | CRC Parameters, Low 24 VAC, Low 24 vac, No Error Stored |
| Temperature Sensor | 5 | Inlet Sensor Fault, Outlet Sensor Fault, Sensor Open, Sensor Shorted |
| Ignition | 4 | Flame Fail Ign, Flame Sequence, No Flame Ign, No Flame Running |
| Pressure Switch | 2 | APS Open, Gas Pressure SW |
| Flue | 2 | Flue Sensor Fault, Flue Temp Limit |
Parts & Prices
The parts most often involved in the Lochinvar faults listed above.
Prices and availability vary by region and are shown by the retailer, not by TroubleAtlas.
Diagnostic Tools
What an engineer uses to work through the codes on this page.
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If your Lochinvar appliance is over 10 years old, replacing it with a modern condensing boiler or air-source heat pump could cut energy bills and remove the recurring faults listed on this page.
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