Another AC Question

[rumrunner]

As some of you may have read in a previous post, my ac will run, heat the boat, etc. however it will not cool. I am thinking it may be the Reverse Cycle Solenoid. Is there anyone with some AC Knowledge that could tell me how to test a Solenoid? It seems it would be an easy fix if the Solenoid is the problem.

Any advice would be appreciated.

 

[jg300da]

The solenoid coil is nothing more than an electromagnet. Apply voltage and the coil magnetizes and lifts a pin in the valve stem. The easiest way to test it is to place a screwdriver blade against the coil while applying power. If you can feel the magnetic pull the coil is fine.
To diagnose the mechanical part of the reversing valve requires a set of refrigeration gauges to determine the correct charge. The valve requires enough pressure differential to move it's piston to make the changeover. A system that is short of refrigerant will sometimes not produce enough pressure differential to operate the valve. The other cause can be a damaged or sticking piston. Much less common.

 

[fc3]

The normal position of the reverse valve is "cooling" when power is applied it switches to "heating". This is audible aboard Just Ducky. I can hear the solenoid switch when the unit goes into heating mode.

You can check that the coil is not energized when in cooling mode. You can also try switching to heating and then back to cooling to see if the plunger will cycle. Think you're going to need a tech if cycling the system from cool to heat and back does not work.

 

[Robski97]

Franks right. If coil was bad it would default to cooling. U wouldnt get heat. Pull a wire off the solenoid. ( might be wired wrong or hung up relay on circuit boad ) See what happens . Ill bet thats it


rob