MarineAir System Issue

SG · Aug 18, 2019

Hi - I have a 2004 Hunter 44 DS and there is an issue with the aft air conditioner, forward unit works fine. The Passport control does not seem to want to switch from the heat cycle (heat works fine). I’ve run it through test mode and the air conditioning kicks in and runs fine so I’ve ruled out the reversing valve. Anyone have a similar issue and solution? Is there a re-set on the Passport control panel back to factory settings?

I'm confused, does the Cooling work or doesn't it? I would have guess the reversing valve too.

SG · Aug 18, 2019

If the control unit is the same for both the forward and aft units, you might try swapping them to see if you can isolate the issue to the control module. I think that's where the control boards are located.. Call "Marine Air" (now Dometic, I think) and ask them.

SEMPERAVANTI41 · Aug 20, 2019

I had to swap displays to find out the display was the problem when my salon A/C refused to allow temperature adjustment. On my boat, the displays were held in place with double stick tape. It was easy with a credit card or plastic scraper to get between the cabinet and the display to free it, in less than 5 minutes. Then just plug the "good" display in and you will know immeadiatly where the problem lies.

JamesG161 · Aug 20, 2019

I am experiencing the same problem on my Newest Dometic Turbo 8KBTU unit.
I am not through trouble shooting yet, but will know for sure by the weekend.

In the test mode, the cooling cycle worked fine and I made sure the seawater flow was maximum and it was heating in the cooling cycle.
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The start up relay "chattered" on my unit.
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I bought a new control cable since it appeared that the "plug in" at the power box was the problem.
So we will direct plug from display to power box for a test.

I think it is the power box printed circuit board, at this point.
You will need the serial and model number for the newest Dometic products.
Jim...

JamesG161 · Aug 20, 2019

I will take pictures and let you know. Going to boat tomorrow morning for testing.
Jim...

SEMPERAVANTI41 · Aug 20, 2019

Jim, if the relay is "chattering" the problem could be the control board, the connecting cable, the connection for the cable on the board, the display or the relay itself. Sometimes I have found the problem just to be a weak connection between the cable and the board. You might want to try spraying the connector on the board with electronic cleaner and re insert the cable.

JamesG161 · Aug 20, 2019

SEMPERAVANTI41 said:
Jim, if the relay is "chattering" the problem could be the control board

That is my guess too. We took out the board and double cleaned and verified it was the possible board control cable cord.
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jhagg said:
I found a copy of the Passport control manual

I was going to PDF mine to you but mine is Dometic 2016 version.
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My 16kBTU front cabin unit keeps on chugging along.

Jim...

JamesG161 · Aug 20, 2019

For future reference , here is a picture of the 2016 Dometic circuit board.

The Marine Air Display Jack is what we thought at first.
Jim...

JamesG161 · Aug 22, 2019

It was the circuit board.

The display cable plug "Marine Air Display Jack" apparently fatigued and broke the clip to circuit board.
Hard to find, but explains the chattering from slight vibrations on startup.

I am trying to verify the most updated PCB from Dometic.

New Tip: Make sure your display cable has strain relief inside the power box.

Jim...

SEMPERAVANTI41 · Aug 23, 2019

Sounds like something that could be repaired with a soldering iron. I wonder how much the board will cost?

JamesG161 · Aug 23, 2019

SEMPERAVANTI41 said:
Sounds like something that could be repaired with a soldering iron. I wonder how much the board will cost?

In my youth, and a pinpoint soldering iron, I would have done that.

Cost about $280

But the kicker is the PCB release number. Mine is release "00F" which I heard was now OLD [late 2016]
If you look at the picture above it was release "00D"

SEMPERAVANTI41 · Aug 23, 2019

FYI, I replaced the salon A/C last year in my 41DS with a new Dometic replacement unit. It came with a new display, with a different design from the old one. I was able to use the old display with no problems with the new replacement unit, just plugged in the cable. I bet the control board is also the same even though there might be different release numbers.

JamesG161 · Aug 23, 2019

Ok after finding the correct place to call, I got the newest control board called

"Unity Board"

Guess why?

SEMPERAVANTI41 said:
I bet the control board is also the same

Where is my beer?

I called Dometic Tech service, got a Tech , told him the problem and he gave me the part number "223100502".
Told him the "fatigue" issue he said they normally make a loop with excess cable and wire wrap that loop for
"sail boat" strain relief.

He asked my location for a Distributor near me. Long story, but that Distributor is mad at me since I didn't buy a new Grunert Frig unit for $5200. [I replaced the compressor for $500]

He gave me the Dometic "Big" Distributer in Texas "AER Marine" 800-767-7606
Called them and will get the board on Tuesday, total cost $279 [saved $21, no tax , no shipping]
Jim...

PS: Dometic auto caller and they listed 6 brand names of marine Air systems. Unity is needed.

JamesG161 · Aug 27, 2019

Just got my new board. Version 00K.
Look close at the solder break on my old board.

I had to press down on that connecter to show the breaks. Hard to find at first.
Jim...

PS: The new board came with mounting screws also.