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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Why am I getting a "diag, defrost control input fail" on a

Customer Question

why am I getting a "diag, defrost control input fail" on a cooling only 35 ton voyager
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.


It is apparently a bogus error code, however if the unit is not running something else is wrong, if you can send me a clear, well focused, well lit photo of the units wiring diagram I might be able to help you diagnose it. So far I suspect its a tripped high or low pressure switch, or possibly a temperature sensor clipped to the cooling coil that is the problem.

Use the paper clip icon at the right end of the tool bar above to send the photo.