Originally Posted by Finn.G
I have a similar problem as OP. The fan comes on and there is a high pitched noise but the compressor does not start. Per Richard's recommendation i pulled the fan wires from the controller and now the high pitched noise comes on every thirty seconds or so and no compressor.
The compressor is a Frigoboat AH12 and the controller is a E250154.
thanks in advance, Greg
The high pitch
sound you hear is the 20 years plus old style module preventing compressor from starting do to a fan drawing more than one amp, or a low voltage spike, or amperage load of compressor module excessive. After you have completed the normal test then you will require another control module as a test or fix. If someone has tampered with refrigerant too much refrigerant will prevent module from starting compressor. Low on refrigerant will not cause the high pitch
sound or prevent compressor from running
Troubleshooting 4 pin modules consists of the following:
1. Place jumper wire across thermostat terminals, Compressor still does not run.
2. Disconnect black fan wire from electronic module, Compressor runs replace fan. Compressor still does not run after fan ground wire is disconnected. If one of the 10 transistors in this fan fail it can cause module to prevent compressor from running.
3. Run correct size and correct polarity fused jumper wires direct from a fully charged battery
to module in order to bypass all boat’s wiring
. Volt meter readings are of no value, Compressor still does not run electronic module needs to be tested on another unit. A refrigeration
sales person will try to sell you a new system when solution is electrical
. Because these 4 pin modules are no longer available look for one on Ebay or From wwwRparts.com. Any one of the 10 four pin connector Danfoss modules will operate your compressor. The E250 module you ave now is a Frigoboat replacement for the original 12 volt.