Model reference
Lennox HS21-048
Air Conditioner
1 document13 error codes3 service modes
Available documentation
Service Manual
- HS21 Series Service Literature26 pg
MyPros+ Max
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Error codes (13)
CodeMeaning
1Power loss for two electrical cycles (33-40 milliseconds), suggesting dirty or…10Option 2 safety device switch opens.11Compressor temperature sensor wires have shorted together.14Control is in TEST mode; does not indicate a problem.15Mode jumper is not in place on the TSC5 two-speed control.2Input indication3Unsteady thermostat input4Pressure switch opens after compressor has run for less than two minutes, may…5Pressure switch opens after compressor has run for more than two minutes, may…6Compressor temperature exceeded its limit after running less than five minutes…7Compressor temperature exceeded its limit after running more than five minutes…8Option 1 safety device switch opens after compressor runs less than five…9Option 1 safety device switch opens after compressor runs more than five…Service modes (3)
- Diagnostic Code Recall1
- Manual Override (5-minute delay bypass)Press and release the manual override button on the TSC5 (A14) control to bypass the five-minute…
- Test Mode1
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