Outdoor unit thermistors provide thermal feedback that affects compressor staging, protection behavior, and stability. If these signals are wrong, the system can look like it has compressor or PCB failure when the actual fault path is sensor-related. Verification should be explicit before any major part scope.
Primary question
Could an outdoor thermistor fault be causing unstable compressor behavior and incorrect replacement recommendations?
Outdoor thermistors are mounted at temperature-critical points in the condensing unit.
Their readings influence protection logic and how the outdoor system responds under load.
When outdoor sensing is inaccurate, cooling stability and protection behavior can become inconsistent.
Outdoor thermistor symptoms can overlap with other outdoor problems.
A reliable conclusion should separate sensor path from mechanical and control look-alikes.
Replacement is more defensible when outdoor thermal signal behavior remains inconsistent after wiring and look-alike checks.
If recommendation jumps directly to compressor or board replacement without sensor-path evidence, request one bounded verification step first.
Learn what outdoor compressor faults look like and what to check before agreeing to compressor replacement.
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Tell us what is happening. We will assess first, advise one clear next step, and you decide.
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