Oasis Heat Exchangers Hot when Furnace off

[RetireeKeith]

I had the same exact problem about 10 months ago on my 2016 Dutch Star. The same check valve was replaced and the problem disappeared.

ITR sent me a check valve for free.

Keith

[LK23]

Update: A week after tapping the check valve and the Oasis is still working properly. I received a new check valve and attached several photos showing the flapper valve. I also have photos of the location of the check valve in the distribution box. The system #1 check valve for the front half of the coach is on the left.

[LK23]

Once again, we are experiencing hot heat exchangers after the furnace shuts down—stuck check valve.

Today, I replaced the check valve in furnace system #1. System #1 controls the front half of the motor home. My biggest problem was removing the rubber hoses from both sides of the check valve. After removing the hose clamps, the hoses were stuck on the hose barbs and difficult to remove. Once the hoses were removed, I removed the screws from the stainless steel box around the check valves and the check valve fell out with hose barbs intact.

I replaced the pinch type hose clamps with airplane clamps—much easier to work with.

See Photos. The first photo shows the new check valve mounted inside the stainless steel box and the second photo shows the output end of the check valve on top of the distribution box.

[rewillia]

Good summary of the issue, cause and repair.
Thanks for posting.

[barnegatepic]

So this explains why I always felt the warmth coming from under the kitchen sink. I'm guess that you pinched off the hoses prior to removal and had little loss of fluid?

[dc3carl]

Be sure the rocker switch on top of your silver box is turned off. This switch will run the distribution pumps constantly and circulate hot fluid. I was erroneously told that switch needed to be on for heat to work.
That switch is for purging air from your Oasis system