CruiseAir issue.

[WanderIVth]

We have a cruisair 12k btu and 16k btu unit is installed on our catamaran. The system as a whole worked perfectly well since we got the boat in April, but that’s changed the past few weeks. The 12k system is now having issues.

The first issue we had was with the breaker tripping for the aft cabin AC. The first time it flipped off, we turned it back on and it ran fine for a little while, then started switching off after only a minute or two, then tripping immediately. We saw that the breaker capacity on that line was too low for the load, a 15 amp breaker when the minimum suggested was 20. We replaced it with a 25 and it seemed to fix the problem. May not be connected, but I don’t know.

Last night, I noticed that it wasn’t as cool as usual with the AC on. When I listened for the compressor to turn on, I heard it make the initial quieter hum that it does as it prepares to kick in, but then it just shut off instead of cycling up. This happened about once every minute or two, and I could tell it was trying to turn on, but something was stopping it. So I turned the lower AC off from the control panel, but that started VERY loud buzzing noise coming from the pump relay box in the hallway I turned the system back to “cool”, and the buzzing stopped, but the AC still could not kick on. I hit “off” again and the loud buzzing noise came back. We determined it was coming from the pump controller. I intended to hit the “cool” button again to make the noise stop, but accidentally hit “off” again. That stopped everything. And here we are.

I have purchased a clamp amp meter to try to evaluate the compressor but was wondering if anyone else had ideas.

The water pump is shared between the two units and the second unit is functioning normally.

[Chili Palmer]

I don't know much about the AC unit but I would be worried about sending too much current through that wire that originally had a 15amp circuit breaker.

[WanderIVth]

Originally Posted by Chili Palmer

I don't know much about the AC unit but I would be worried about sending too much current through that wire that originally had a 15amp circuit breaker.

The installation guide called for a 20-30 amp breaker for it. I went with a 25, right in the middle.

[Act Three]

I have a similar setup on my cat. Cabin AC working great, saloon AC would not kick in. Went back to sea water pump and check power to pump from each unit. Cabin unit was sending power to pump, Saloon uni was not. Change the leads and ran test again, still the Saloon uni would not send power to pump. That is as far as I would go. Called service man and he ended up replacing circuit board in Saloon unit and replacing a couple burnt wires. He left me the board and the connection area of a couple sites looked crispy. About $375 for board plus labor.
Hope this helps.

[Tin Tin]

Have you checked that sea water is being expelled out the side of the boat when you start the aircon. You may have an air lock in the water pump">raw water pump and it may need to be bled, or the pump may be stuffed. What model cat?

[WanderIVth]

Originally Posted by Tin Tin

Have you checked that sea water is being expelled out the side of the boat when you start the aircon. You may have an air lock in the raw water pump and it may need to be bled, or the pump may be stuffed. What model cat?

I have. The water pump was running the whole time and cooling the other AC just fine.

[Tin Tin]

So you have one pump that services two units, so maybe the raw water feed to the non performing unit is blocked or restricted assuming it does not have its own outlet. If it does not have a separate outlet, then you can disconnect the feed to the good unit at the T after the pump, block the end of the T and see if it still comes out through the dud unit.

[WanderIVth]

Originally Posted by Tin Tin

So you have one pump that services two units, so maybe the raw water feed to the non performing unit is blocked or restricted assuming it does not have its own outlet.

The pump goes through a tee that goes to each unit and then back out a single through hull. It's possible it's clogged up on just the one side, but I don't know why that would affect the compressor starting up.

[Coolerking]

Does the pump run when the affected unit tries to start?
Was the condenser tubing hot,( where the seawater passes through)?

What kind of control does it have and is there a fault code shown?
There is a high pressure cutout that will prevent the unit from running, it will take a minute to happen the first time but it will begin to shut down quickly as the heat buids, eventually causing the system to pull too many amps and thus either shut down on the overload on the compressor itself or trip the breaker.
Please keep in mind the fact that the breaker is sized to the wire, not what is running on it.
What size is wire on the main power feed to the unit (L-1 And N/L2)?
I would start the unit that works, then confirm water and put hands on the condenser shell, then while that is running start and compare it to the unit with issues, if the pump is running and the unit runs then you have a bad pump relay trigger, if the pump runs and the unit gets hot, then you have a blockage or a fouled condenser, and it can be cleaned by flushing it out with a diluted solution of barnacle buster.
I assume that you have a separate breaker for the seawater pump?

[Tin Tin]

The other thing that goes on these units is the trigger solenoid, easy to replace, the ac will run, but the solenoid will not trigger the reversing valve or the valve is stuck, they can burn out and are obvious if they have.


Example is https://citimarinestore.com/citiguid...Price-List.pdf part number 4071603 (for 230V)

[geoleo]

Originally Posted by WanderIVth

We have a cruisair 12k btu and 16k btu unit is installed on our catamaran. The system as a whole worked perfectly well since we got the boat in April, but that’s changed the past few weeks. The 12k system is now having issues.

The first issue we had was with the breaker tripping for the aft cabin AC. The first time it flipped off, we turned it back on and it ran fine for a little while, then started switching off after only a minute or two, then tripping immediately. We saw that the breaker capacity on that line was too low for the load, a 15 amp breaker when the minimum suggested was 20. We replaced it with a 25 and it seemed to fix the problem. May not be connected, but I don’t know.

Last night, I noticed that it wasn’t as cool as usual with the AC on. When I listened for the compressor to turn on, I heard it make the initial quieter hum that it does as it prepares to kick in, but then it just shut off instead of cycling up. This happened about once every minute or two, and I could tell it was trying to turn on, but something was stopping it. So I turned the lower AC off from the control panel, but that started VERY loud buzzing noise coming from the pump relay box in the hallway I turned the system back to “cool”, and the buzzing stopped, but the AC still could not kick on. I hit “off” again and the loud buzzing noise came back. We determined it was coming from the pump controller. I intended to hit the “cool” button again to make the noise stop, but accidentally hit “off” again. That stopped everything. And here we are.

I have purchased a clamp amp meter to try to evaluate the compressor but was wondering if anyone else had ideas.

The water pump is shared between the two units and the second unit is functioning normally.

I inherited a 12000 Cruise Air late 90s model on my boat. The plastic plug between the unit ant the controller was led over the compressor . Over time this plastic deteriorated from the compressor heat below--- it has 5 wires. I saw the light and bought a new Webasto.

[Chili Palmer]

Originally Posted by WanderIVth

The installation guide called for a 20-30 amp breaker for it. I went with a 25, right in the middle.

What size wire is behind that CB? Can it handle the 25 or was it designed for the 15?

[a64pilot]

I don’t have a Cat, but I do have two AC’s.
I know most often multiple AC’s for purposes of saving money run off of one thru hull and one water pump.
I don’t like that as it’s too many single points of failure for me, lose a pump, strainer clogged, relay box that drives the one pump etc and you lose all Airconditioning, not just one.
I just got through replacing the AC in our Stateroom last week. Luckily it was on sale at Defender, but until it came in, we stayed cool by running a fan in the Salon and blew air into our Stateroom, even a few days without AC would have been miserable stuck in a Marina with zero wind and it raining every day.
Having independent systems pretty much guarantees one will continue to function.

For Gods sake for things like AC units etc, run 10Ga wire, yes it’s overkill, but it’s just pennies difference in price and why not have extra current carrying capacity? Plus as I carry spare wiring, it’s much easier to carry 50’ roll of 10 ga for all AC wiring demands and a couple of sizes for DC.
Marine tinned wire can be hard to come by out in the wild, as can good CB’s so carry a few of them too.