Cruise Air Trouble Shooting Help Needed

[Eddieclemons]

Guest stateroom Spilt 7k Unit

Problem- When in the cool mode the compressor starts and then kicks out after about 30 seconds. This will repeat 3 times and the SMX will give the old Hi PS code. Raw water temp and Ambient temp are both in the low 70's.

Things I have checked so far.
* Good raw water flow out disconnected hose at exhaust inlet from compressor coil.
* Good water flow out the exhaust when raw water is connected. No obstructions in exhaust inlet found
* When gauges are connected to unit to check R-22, Discharge pressure never exceeds 150-175 before the compressor kicks out.
* I checked HP switch and it reads closed. I installed jumper and had the same faults.
* I switched out a SMX controller and still had the same faults.

Raw water pump is less than a year old.
Barnacle buster back flushed last summer when boat was moved to freshwater.
Return air filter is clean.
Condenser air fins are clean.

I can't get the suction side gauge port shut off to open, so suction pressure is unknown.

Heats like a champ and worked flawlessly the winter.

Any and all help is appreciated. Thanks

Phasma2128's thread and others have been read, and I am still stumped.

 

[rsmith]

Check start and run capacitors

 

[Pascal]

Check the coil and the compressor temp during the 30 seconds the compressor is running. Do the coils gets room hot to touch? If the compressor gets too hot it will trip its heat safety switch although that wouldn’t trigger HPF.

 

[rsmith]

Check the coil and the compressor temp during the 30 seconds the compressor is running. Do the coils gets room hot to touch? If the compressor gets too hot it will trip its heat safety switch although that wouldn’t trigger HPF.

That too. It’s usually a bi metal clicker deal mounted in the electrical connection box on the compressor

 

[Eddieclemons]

Check start and run capacitors

I will check those.

 

[Eddieclemons]

Check the coil and the compressor temp during the 30 seconds the compressor is running. Do the coils gets room hot to touch? If the compressor gets too hot it will trip its heat safety switch although that wouldn’t trigger HPF.

Compressor 75 degrees, and HP tube right out of compressor is 85 and going up before it kicks out?

 

[Pascal]

Are these temp when it shuts down? That’s low…

 

[Eddieclemons]

Are these temp when it shuts down? That’s low…

Yes, never above 85-87

 

[Eddieclemons]

Run capacitor changed, and high temp bi metal switch bypassed, still no change.

 

[Eddieclemons]

Every electrical component on the compressor has been checked and or replaced. (Thanks to POs for having such a great spare parts inventory on board) I jumped the HP switch input on the control board and the problem is temporarily SOLVED. 55-57 degrees at the register.

I will now double check the terminals and if needed run a new twisted pair from the ER to Guest State RM.

I am tired.

Thanks to everyone, you all are amazing.

 

[Pascal]

Great. Glad to hear

 

[Eddieclemons]

Every electrical component on the compressor has been checked and or replaced. (Thanks to POs for having such a great spare parts inventory on board) I jumped the HP switch input on the control board and the problem is temporarily SOLVED. 55-57 degrees at the register.

I will now double check the terminals and if needed run a new twisted pair from the ER to Guest State RM.

I am tired.

Thanks to everyone, you all are amazing.

Well I think I am done for the day. Still unsure of the problem. After a lot of checks the following is repeatable.

If run as normal the high pressure switch goes to open when the compressor is running which causes it to turn off, then the circuit closes.

When you install a jumper in the wires at the High Pressure switch with the switch disconnected you still see a open at the control board when the compressor is on, goes back closed when compressor is off. The makes no sense, but is repeatable.

Jumper the HP circuit at the control board and system works as should with normal high side pressures and compressor never reaches 100 degrees at the compressor discharge tube or compressor body.

I will run a new twisted pair of wires but I really don't see it working.