325 Carver Marine Air Passport II

[Viper]

As Tom mentioned, just to clarify, you are looking for a separate control box that is not part of an actual AC unit. It may be close to one depending on where your units are located but this box is separate and will have wiring going to it from each AC unit on board. Typically a white box about 10"x10"

[nazinteck]

Thanks Viper. I have located that box in the bilge near my water pump and it is indeed separate from both AC units. The circuit board in that box seems to be called the Power Relay Board. The 110v from the boat CB panel for the AC water pump terminates there and the AC source for the AC water pump comes of the terminal board. It is where I read the zero volts yesterday to the pump last night. I will re-check the AC V readings again with both AC units running and calling for the pump to engage electrically at the pump terminal. I also want to make sure all my other wires in the system are secure as well. Whatever the problem is, it is common to both units as neither will cool, but they both do operate. The pump also works outside the "system." If I have 110V from the breaker box and then nothing at the terminal for the water pump, I suspect it is a circuit board problem. If that is the case I will try to find the relay and replace it IF I can find one. Thanks all. I appreciate the help.

[tomschauer]

If its as hot there as it is here this week, a temp fix to provide you a/c would be to bypass the board by connecting the CB pump feed to the pump wires. Let it run and turn of the breaker when not running the ac until you get a new relay.

[Midnightsun]

Been there done that. I had a pump go once on a previous boat. Hooked up an aquarium pump as a temp fix until I was able to get the real thing. Worked just as good.

[nazinteck]

Great idea. I will do that as the 10 day going forward looks hot and humid!

[km1125]

On my temporary A/C hook up for my aft cabin, I just have the pump on a separate circuit. I plug that in and let it run and then turn the A/C on and the A/C will cycle on the thermostat but the water pump just continues to run.

Because it's running continuously, you might want to check and clean the strainer more often.

[Keith S]

If the board is bad, check out flightsystems.com for repairing the boards for less $$

[nazinteck]

My 325 Carver has an OEM separate circuit for the AC pump, so I directly wired the pump to the 110V source and the system worked fine this weekend. i appreciated the work-around tips as it was very hot and very humid this weekend. So I now have a bad pump relay board. I have a MarineAir Series III Pump Relay as identified on the board. I plan to look for a replacement online today and also look into the flightsystems.com repair service that Keith S suggests above. I would like this operational prior to haul-out.

[nazinteck]

I found a good source for replacement AC Pump Relays. Micro Air is the manufacturer of relays for several brands of AC. I spoke directly with the engineer staff there and they recommended their P/N 111 as a direct replacement board based on the markings of my current CB. So I ordered it from their web site www.microair.net. Since the customer deals directly with the manufacturer the board cost $98.00. Shipping is two business days through USPS at an additional $14.03.

[g36]

i've had good dealings with microair also. thanks for posting your findings and results