A/C unit not pumping water (new pump)

Hey guy, hopefully you can help with my a/c and heat not pumping water but blowing air correctly.

The a/c was pumping water correctly, we had the cabin set at 68 degrees and one night was a little colder, so we set the temp to 70 degrees before bed. We had the system on Auto and woke up with the inside temp at 75 degrees and the water hasn’t pumped out the side of the boat since.

I’ve tried the a/c and heat on the thermostat, both appear to work correctly from the fan providing air. I have tried switching the thermostat to heat, a/c and auto with no change.

I took the pump out of the boat and determined it wasn’t pumping correct volume of water in our tests.

So, I replaced the pump with a brand new one. Got the boat up on plane, water shoots threw the side of the hall while on plane, nothing in the strainer and no other blockages.

Turn on the a/c and pumps air into the cabin as normal (air seems a little colder) but still no water pumping from the side of the boat and I believe the pump isn’t even turning on.


Where should I check next, is there a relay at the air/heat unit that turns on the pump. Would it be the a/c unit itself causing the problem. Is there any hidden breakers for the pump

There are no errors on the cabin thermostat and continues pumping air until I turn off the breaker. We only have one air condition unit, with one thermostat near the v-berth and one pump in the bilge. Pump appears primed after taking it up on plane today.

One a side note, I have 2 wires in the wiring harness for the a/c unit that aren’t connected to anything. What would they be for? Black wire with #503 and Red wire with #502

2011 350 Sea Ray Sundancer.

A/C is a Cruisair

My interpretation is the question your asking is with a new pump, there is not water coming out of the output in the hull.

First thing I would check is do you have good waterflow from the input through hull.

I would close the through hole, take the tip off the strainer, then start to open the through hull. Are you getting water coming in. If not, there may be something obstructing the through hull fitting or the line.

Sorry, my question seemed confusing.
I got the boat up on plain, and water shoots out of the trough hall fitting and doesn't appear to be blocked.
I believe the water pump isn't even turning on, even though the air is pumping in the cabin.

You need to diagnose the water pump first. When you turn on the AC it should send a signal to the water pump. Make sure you have power to the pump and all thru hulls and lines are clear.

Are you sure you don't hear the pump coming on. Mine is quiet, but I can still hear it in while I am in the engine compartment...
Every start of the season, my system gets air in in. My pump will not push the air through. I have to shut the thru hull valve, disconnect the hose coming off the pump going through the ac unit, connect a garden hose and flush water through it for a few seconds. Then reconnect everything back up. Works fine for the season!!! Oh, and DON'T forget to open the thru hull again!!! otherwise you will have to repeat the process....

Update ***
I was able to get the ac/heat working correctly with water shooting out the side of the boat.
- I had no power at the pump and traced the wire back to the computer board.
-Power In,had 112v on L1 and n/L2 (correct)
-Power to the pump I had between 35 to 50 volts ( N/L2 and pump). This should also be 110volts.

I removed the black wire from the pump lead and put it with the main L1 and the pump fired up and began to flow water.
sounds like it was the output on the board that has failed and I need a new board. I am fine using the board this way for now and wont be quick to replace.

Thanks everyone for your help and suggestions.

When you decide to replace it, these guys have the best prices. I thought I was going to have to buy one, but my issue turned out to be the high pressure switch....

https://www.microair.net/products/a...r-cruisair-smx-ii-display?variant=29192390539

Bennett

I see your unit is a turbo so it can't be too old. I recommend you call Dometic customer support and talk it through with them. They have been very helpful to me in these situations. Great customer support.

Ours wouldnt flow water through the unit last week either.
I checked the seacock and water entered through but I never heard the pump come on.
It eventually threw the HI P5 code.
so I'm assuming it's either our pump went bad or possibly an issue similar to yours.
Unfortunately, it will be a few weeks before I'll have time to further investigate the issue.

Connect power direct to the pump to rule out any pump failure, then go from there.

Is there anything on the computer board that controls heat?

Heater turns on, i hear the click switching to heat mode as normal. Air blows out, but no heat.
I'm thinking of ordering a new board from the link above. But only 2 weeks left in season

Try "Flight Systems Inc" if control panel is bad. They recondition control panels.

Be careful and be sure to get the correct part numbers. I suspect your control board looks like the one in the link I posted as I also have the turbo unit that was new in 2014-15. The A-288D is the correct board. I would call Dometic if you have any doubt...

Bennett