Funny water pump leak

waynefi wrote:
Thanks JBarca, I think you nailed it. Starting with a cold hot water tank, I turned on the heater and did not flow any water. It started dripping 10 to 20 minutes later. I flowed some water, and it stopped.

The water was dripping from the bottom of the pump. Both inlet and outlet connections felt dry. Since this is a brand new trailer, I’m not sure whether I should go back to the dealer, or put in some kind of accumulator myself.

At least I have a work-around. When I turn on the heater, wait 10 minutes and flow some water. Then don’t turn off the heater until I really need to.

You are welcome and maybe you can help me too. See below after I comment on your post.

Thanks for reporting back and glad you found the issue.

By chance did you look outside at the water heater safety relief to see if there was any weeping of water by the time the heater shut off?

Did you have a typo I highlighted in red on your response above, on never turning the water heater off? Assuming this is a typo as leaving it on will aggravate your issue if you are not using it.

Now what to do, Yes it appears you have work around, a pain but it is something now under your control for the moment. I would personally take pics of the leak, send them to your dealer and request a warranty claim on the pump or ask them what to do. With the back log at dealers now, you may have to wait a good long time to have them troubleshoot, then get authorization, then change the pump. Taking the pictures and explaining the situation, hopefully they will just order a new pump if they do not have one and then schedule a day to install so you do not loose a lot of camping time waiting on this.

The pump should not leak under full system pressure, which is 150psi by the water heater relief valve. Since you have no pressure gauge in the system, and it only took 10 to 20 minutes of cold water heating to start the drip, I suspect from my tests, the pressure may have only rose to 120 or 130 psi. So the pump could be leaking at a pressure lower then the 150psi relief pressure. That lower pressure is what normally can happen if the air cushion in the water heater gets dissolved and even with that air cushion, it will still rise some. Granted your pump pressure or city water pressure is not that high, but the water heater issue is real. I'm sure there are many campers that go undetected as nothing leaks and all is considered OK not realizing what lurks in the background.

As to do you install an accumulator yourself. That is a good thing to do for long term to address this thermal expansion issue, but I would not use that as the fix for the pump. That leak has to be addressed, as leaks generally never get better, they usually get worse and you may end up with a water damage mess. That may not be covered under warranty. Ideally, all campers with a tank style water heater have a bladder type expansion tank. It's one of those things that have not been upgraded into new campers. I suspect it is a cost saving thing on the manufactures part but it is for sure a need.

I restore water damaged campers. It is a retirement hobby I have gotten into. I am now on my 15th water damaged camper, some minor and others major restorations. Maybe I'm nuts wanting to deal with rotted wood, but I enjoy the work and my friends are very grateful I help them out. I have seen so many kinds of camper water damage leaks it's sort of amazing they last very long at all. You do not want "any" leak to go undetected for any length of time. Your only good luck in a water leak situation is, you find the leak as soon as it starts, mop up the mess quickly, and create efforts in short order to stop any more leaking.

Something you can help me with is feedback on two things.

1. What brand/model water pump do you have?

2. What brand and model water heater do you have?

I'm trying to track down some more data on the new design Dometic/Atwood water heaters. I installed one of the new ones this spring to retro fit into an older Atwood location on a camper restore I was doing. There was some very immediate high pressure issues when water was heated, worse then yours. I have my own thoughts on why this happened, but I need more data from other users to help confirm my thoughts.

Let us know how you make out.

John