Fault codes covered
36-15, 36-55
Code 36-15 occurs when the low compression boundary is crossed and AEM cannot adjust system operation to increase compression ratio. Before this fault is set, AEM will automatically reduce outdoor fan speed (cooling only) to increase CR, then increase compressor speed. 4 occurrences of code 36-15 within 2 hours will result in code 36-55 and 2 hour lockout. Low compression ratio can be a result of compressor not increasing pressure adequately or low system charge.
Source: ACHPVSR454-02SM troubleshooting pages.