Dometic STX12

[tonyiiiafl]

I was running the new rudder indication for my Ray Auto Pilot today and had to get under the bed in my 390 CPMY. I was aghast at what I saw on the rear AC. Doesn’t’t seem to be leaking, but have never seen this before. I guess I am about to BOAT? Beak Out Another Thousand? Is there a direct replacement that anyone k owns where I could just replace the unit and leave the controls and wall thermostat in place. I guess I am glad I saw it, but again, NO leaking, just ugly!

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[RGrew176]

Good catch.

[tonyiiiafl]

I NEVER leave it on 24/7. I will turn it on a few hours sometime before we arrive or leave it on if we go ashore, but this could have been devastating for sure!

[bud37]

That seems to be a bit of what appears in the pics to be corrosion.......how is the bonding for that particular unit, all clean and good connections...??

[Midnightsun]

Hard to tell by the picture but it looks like you have quite a bit of standing water in the bottom of pic 2. Almost looks like mineral buildup which would really not matter all that much.

A pet peeve of mine is water in the AC tray. I always have modified or corrected the unit by shimming it so water flows almost entirely out when at rest at the marina as a base. No matter how you slice it or dice it, standing water becomes stagnant which is not a good thing. Maybe just a clean up and rethink the drain on your unit is all that is needed.

[tonyiiiafl]

There is a lot of water in the drain pan, and there is dried minerals like salt all over. The drain hose is plugged from the pan. I was thinking of taking a fresh water hose from outside washing the unit down gently without hitting the electrical parts and then seeing if there is a leak. I never saw that until this year, so it is very possible it is just plucked I would think?

[tonyiiiafl]

I am going to take a shot at cleaning the corrosion off. I figured the bilge pump activity is due to the drain pan over flowing rather than going to the shower drain pump. There is a lot of griat and mineral deposits in that pan. Last year it was pristine. I was going to lightly brush the corrosion away and then use either air or a slight spray from a fresh water hose. The pan will be a challenge to get clean, but I am sure I can. What would you all use to spray on the corrosion to try and help my brushing? I was going to use a baby bottle brush and a nipple brush and tediously brus away, then hose it all down. That way I can give it a week to dry off before testing it. It still cools and heats GREAT! I hate to spend $2500.00 if I don’t have to!

[tonyiiiafl]

Here is some more of the ugliness. I got the fan shroud off and the TEE, it looks like the pan Darin is plugged causing the water to over flow, and also splashing of drain water to create the corrosion. I am. Going to clean it all up, and see what it does. I now do NOT think it is a water leak, just crud, and perhaps a bad bonding wire. I have to hunt that wire up!

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[Viper]

Source of the post...perhaps a bad bonding wire. I have to hunt that wire up....

I don't think there is one.
On first glance it looks like salt deposits so my first suspicion is that you have a raw water leak. Disconnect the raw water inlet and outlet, plug one end and make up a rig to do a pressure test. Then you'll know for sure.

[bud37]

Now those particular pics do look like a water leak......it was the earlier one with the green/white dry deposit that looked a little funny. I agree, clean it up and see.