Marine AC losing charge but no visible leaks

[wunderluster]

I have a 2 year old unit that has worked great until recently. I was running it on reverse cycle when I noticed it wasn't heating the boat very well. It was showing an error code for low charge.

I removed the unit and had a friend who is in the marine air business install ports. The Webasto unit came new without ports. He had trouble getting the ports to seal because there is very little room to work. Anyway, he finally got a seal on the ports. But, the unit is still losing charge at the rate of 1 lb every 10 minutes. I removed all electronics and put the entire unit in a tub of water. No bubbles, put it is still losing charge at 1 lb. per 10 minutes.


How can I find a leak that doesn't produce bubbles under water. I know there is a dye and I would try that if the leak was really slow.

Is there any way the unit can lose charge inside itself?

BTW, I bought this unit new for half price because it had been in storage for 4 years so, no warranty.

[a64pilot]

A lb is 10 min is a HUGE leak, ought to be audible it's such a big leak.
No, there is no way it can leak that much and not leak to the atmosphere.
I would suspect a leak in the sea water cooled loop, in cool mode, it's the condensor, but that big a leak should be real easy to find, ask for your friend "sniffer" it's an electronic leak detector for finding leaks.

[accomplice]

With a leak that big, fill with nitrogen and listen for hissing.

[rwidman]

It may be leaking internally in the heat exchanger. You can't find the leak and you can't fix it either. I've had two fail this way. As for a warranty, Cruise Air's warranty is worthless. Five years on the compressor, one year on the rest. Since the compressor was ruined by seawater getting into the refrigerant, they told me "sorry Charlie".


I replaced it with a different brand (Flagship) and I chose electric resistance heating instead of reverse cycle. This simplifies the unit and cuts compressor wear in half.

[Johnniegee]

Refrigerant with dye should do it

[ttamerler]

Can't help you with fixing the leak but as a replacement check out a Mermaid unit. Made in America and a 5 year warranty.

[rwidman]

Originally Posted by ttamerler

Can't help you with fixing the leak but as a replacement check out a Mermaid unit. Made in America and a 5 year warranty.

Check that warranty very carefully. Read my experience above.

[Hard Rock Candy]

Are you reading the one pound from a pressure gage? If so that is One pound per square inch and it would take hours to bleed down very much for that small a leak. I assumed that you were reading it from how much you used from the container. Mac

[TKDSailor]

Originally Posted by ttamerler

Can't help you with fixing the leak but as a replacement check out a Mermaid unit. Made in America and a 5 year warranty.

Mermaid is great- located in Ft Myers, they checked my 20 year old unit and it is still working fine... aboard Ark, 2 boats away from you! Best of luck!