Dash Air Blowing Hot!

[DaveKingston]

Update #2

I finally got back out to the coach the other day to try some of the troubleshooting tips that have been posted here, thank you all.

I rechecked the function of the AC clutch and it does seem, at least to me, to be normal. It engages in both AC and Max AC modes and also in Defrost mode.

I clamped the "hot" coolant line from the engine between the Evap assembly and what looks like a valve or switch on the coolant line. On startup when the engine was cold The Ac seemed to work fine. I was getting 40 degree air from the vents, ambient temp was around 75. When the engine warmed up the air from the vents warmed up to ambient but at least not to blazing hot as before. see picture.



I am going to attach a few more pictures and if one or more of you fine folks can help me identify them and their possible role in diagnosing my AC problem I would be very appreciative. The Evap and Plenum assemblies are easy, they are labelled, LOLOLOL. As I said be gentle. As a commercial piot I have a pretty decent understanding of how various systems function but have zero familiarity with automotive AC systems. I also have an understanding with the A&P mechanics at my work, "I break it, you fix it" It is a job security thing.

[RamiDav]

I'm pretty sure the black device in the red hose is the water cut off valve
It may also be variable to serve as a temperature control .
Since the air is cold early on and then heats up indicates to me you are still not
getting the water flow stopped or at least not completely enough .
It appears it doesn't take much hot water flow to over power the cold .
I assume the blue device in the top picture is a clamp , I'm not familiar with it .
Can you adjust it , make it tighter ? The valve looks to have wires connected and
doesn't appear to be where you could see if anything is moving when you operate the
inside controls but maybe you can hear or feel if anything is happening within it .
Anyway I believe this is the area troubling your A/C .

When I move my inside control from hot to cold it takes quite awhile for the
heat to clear from inside the coils etc and begin to blow cold air .

Ray

[DaveKingston]

Yes the blue item in the first picture is a clamp as suggested by @RobRoy. It did seem to slow down or at least limit the amount of heat getting through but as you said not enough to allow the cold AC to over power it.

There are a number of screws on the valve and I was wondering if it is safe to remove them and the cover to check the function of the valve without getting covered in hot coolant. Also if I unplug the electrical connection wil the valve fail in the open or closed position?

Thanks

[shootist]

I would buy a simple cable controled valve and install it.Filing that eletronic one in the round cabinet.

[RamiDav]

Originally Posted by shootist

I would buy a simple cable controled valve and install it.Filing that eletronic one in the round cabinet.

Don't do anything while its hot the coolant can be under
pressure , blow out and scald you . An auto parts store can
provide you with a manual or cable controlled valve .
The new valve can be inserted in place of your present
valve . You can then shop for a new elect valve at
your leisure if you want to keep it original .
I would be tempted to install a simple manual valve that
I just turn off in the summer and turn it back on in winter .
Play it safe .

Ray


https://www.carid.com/four-seasons/h...06d900725b8830

[153stars]

Just in case .Look around engine bay to see if there isn't already a manual shut off that may have been added. Others have added them or had them. Not a bad idea to have shut offs with 60 to 80 feet of coolant hose.

[153stars]

Google Evens heater control valve I couldn't link a PDF
Edit ..try this
https://www.google.com/url?sa=t&sour...Kb4cv5cTkkR5H4
There other nearly identical units pop up low as $45 ....have to get a better look than I can get from your to their pics and need plug view.