System Diagnosis
Low Pressure Control Open. The ICC detects the LPC is open. Note: The low pressure control is ignored for the first 90 seconds of compressor operation.
Rheem | Default
Error Code 21
Troubleshooting guide for the Rheem Default system fault 21.
R
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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