Error code reference

Aprilaire Furnace Error Code Continuous Light

Internal control failure - the WR50A50 control has determined it has an internal fault and has entered a locked-out state.

SourceAprilaire Hvac - Service Manual - RA661001: 1870p. 33

Aprilaire codes Aprilaire furnace codes

Diagnostic procedure

The full Continuous Light procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Replace the control.

SourceAprilaire Hvac - Service Manual - RA661001: 1870p. 33

Unlock with pass

More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

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Where this code is documented

1 manual in the MyPros+ library documents this code for Aprilaire furnace.

Models covered by the manuals that document this code

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The full Continuous Light procedure

Where this code is documented

Models covered by the manuals that document this code

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