Oasis Heat Exchangers Hot when Furnace off

[LK23]

Our Oasis Heat Exchangers in our Kitchen cabinets are hot when the Furnace is not running. We noticed the kitchen drawers are warm and the counter top is warm I grabbed the pipes leading to the heat exchangers and the pipes are hot, emitting heat inside our kitchen cabinet. We recently replaced a defective summer loop pump and the summer loop pump switch is in the Off position.

Any ideas what is causing this?

[LK23]

Update: The heat exchangers in the kitchen cabinets and the half bath are 120 degrees. Other heat exchangers in the bedroom and rear bath are 70 degrees. The Oasis pumps are not running. It is as if the kitchen loop is getting hot water when it should not. Is there a valve that controls where the hot water circulates when on Summer mode?

[ewlee]

Very interesting situation. You said that the summer loop pump was recently replaced and that the bypass switch is in the off position. So is this a new issue since then or has it been since delivery? How much disassembly was involved with the new summer pump? Could there have been lines crossed? With half the radiators hot and the others cold, that is the rub.

[LK23]

Wayne,

Thanks for the reply.

The summer pump was replaced three weeks ago and, since that time, the Oasis system has operated very well. This just happened after relocating to a new location.

The only disassembly with the summer pump was to disconnect the two electric wires to the pump, remove the hose clamps and replace the pump.

I think there are two loops on the furnace since there are two lights on the distribution panel in the basement.

Rex

[ewlee]

Originally Posted by LK23

Wayne,

Thanks for the reply.

The summer pump was replaced three weeks ago and, since that time, the Oasis system has operated very well. This just happened after relocating to a new location.

The only disassembly with the summer pump was to disconnect the two electric wires to the pump, remove the hose clamps and replace the pump.

I think there are two loops on the furnace since there are two lights on the distribution panel in the basement.

Rex

The replacement of the pump was straight forward, same here when I replaced mine. While the pump was malfunctioning, I had the bypass switch on and I would get hot water circulated through the Oaisis radiators, but all of them would be warm. I have now surpassed my knowledge so maybe someone else will chime in. Good luck.

[Norm Mac]

Originally Posted by LK23

Our Oasis Heat Exchangers in our Kitchen cabinets are hot when the Furnace is not running. We noticed the kitchen drawers are warm and the counter top is warm I grabbed the pipes leading to the heat exchangers and the pipes are hot, emitting heat inside our kitchen cabinet. We recently replaced a defective summer loop pump and the summer loop pump switch is in the Off position.

Any ideas what is causing this?

We are having the exact same issue so I am hoping someone is familiar with the issue.
It started on our coach a month or two ago with the exact same heat exchangers. We've been busy traveling so we haven't talked to Oasis or try to get it serviced yet.
For reference: We noticed the problem a few weeks after an annual Oasis service but don't know if it is related. There was no other service done to the unit and we have checked the pumps, summer loop, etc.

[ewlee]

Is there any way that fluid level could affect things, like a check valve or something? Have you checked the fluid level?

[LK23]

I contacted Oasis and it was determined that I have a defective check valve on the Furnace Pump #1 that provides heat to the front half of the coach. This check valve is located above the #1 pump in the distribution box. Oasis is sending the pump and I will attempt to replace it myself. I was told it is more difficult to replace than my previous replacement of the summer pump. See photo of the distribution box and location of the check valve.

Rex

[barnegatepic]

So is it the pump or the check valve that is bad? I believe I have the same issue and was wondering where the heat was coming from under the kitchen cabinet.
What information did Oasis need before they would send you the parts?

[ewlee]

Originally Posted by LK23

I contacted Oasis and it was determined that I have a defective check valve on the Furnace Pump #1 that provides heat to the front half of the coach. This check valve is located above the #1 pump in the distribution box. Oasis is sending the pump and I will attempt to replace it myself. I was told it is more difficult to replace than my previous replacement of the summer pump. See photo of the distribution box and location of the check valve.

Rex

Very interesting. What did they say about dealing with fluid loss when you pull the check valve. When we changed the summer pump, it was the check valve that kept it from being messy and we pinched the line on the down side of the pump.

[LK23]

It's not the pump. It is the check valve above the pump, circled in the photo. If the check valve does not close, any demand on hot water faucets or shower will cause the hot water to circulate through the heat exchangers, even though the furnace is turned off and fans are not running.

Before replacing the check valve, you pinch off the hose above the check valve.

Kevin at Oasis suggested I tap on the check valve to see if I can get it to close. I plan to try that first.

Rex

[LK23]

I crawled into the compartment, removed the front panel on the distribution
box and tapped on the check valve. I will wait to see if if that loosened the check valve and the heat exchangers cool down. Here are a couple of photos. The pump #1 check valve is on the left. In the first photo, you can see the bronze hex cap on the inside of the stainless steel cover over the check valves.

[Itsourtime]

We too are having this issue in our 2017 DS 4369 and as other posters have stated it is intermittent and have yet to have it serviced. For now I'll try tapping it to hopefully get the check valve back into the correct position.

[LK23]

Update:

Two hours after tapping the check valve the heat exchangers have cooled to 75 degrees. They were 120 degrees earlier.

It appears that tapping the check valve worked, at lease temporarily. Note: I used the backside of a crescent wrench to tap the bronze hex end of the check valve in the photo.

Rex