W22 Dash Air Hot

[kschoon1]

I have the "intemittent" dash air blows hot issue as I have seen others describe as caused by the Evans tempcon valve. I have traced the coolant lines from the heater core connection to the engine and the radiator and cannot locate this valve. The A/C system is a Denso. The coach is a 2003 Fleetwood Southwind 35R. If it doesn't have this valve can anyone tell me what type of control switches the unit from A/C mode to Heat? Sometimes the A/C runs nice and cold and then other times it seems to run hot. Mystified!

[abarkl]

Welcome to the club! My '01 has had the same problem since day one.

[max49]

My '04 P32 is like that too. However, as long as I'm moving it stays pretty cool, not 'freeze you out' cold but acceptable.
Stop & Go traffic, I may as well turn it off and put the window down, it's useless withoiut air blowing thru it.

[oemtech]

Run it on Max Air so you don't draw "Hot Engine Air" via the air box intakes. Also Check the "Similar Threads" at the bottom of the page.

Evans Valve


Air Intakes

[kschoon1]

Thanks for your replies and Friendly Welcome! Trust Me - I've spent days researching other posts on this. They all point to the Evasn valve, BUT I am not locating such a valve on this coach. AS I stated I have followed the coolant lines from the heater core connections to the engine and to the radiator - there is no valve in either line. This leads me to believe some other system is being used to cut off the flow or reroute the air flow. Does anyone have any ideas? Mine is very intermittent - sometimes it works great, other times it's as if the heater is running. My control for the A/C is a push button. I've pushed it onand off many times when it isn't working and it doesn't change anything. Still Mystified.

[jdsr]

Quote:

Originally Posted by kschoon1 Thanks for your replies and Friendly Welcome! Trust Me - I've spent days researching other posts on this. They all point to the Evasn valve, BUT I am not locating such a valve on this coach. AS I stated I have followed the coolant lines from the heater core connections to the engine and to the radiator - there is no valve in either line. This leads me to believe some other system is being used to cut off the flow or reroute the air flow. Does anyone have any ideas? Mine is very intermittent - sometimes it works great, other times it's as if the heater is running. My control for the A/C is a push button. I've pushed it onand off many times when it isn't working and it doesn't change anything. Still Mystified.

Mine did the same thing. It took me forever to find out the vac lines were defected. As soon as I replaced them it worked great. BTW I replaced the blue and green because they had very,very small cracks(dryrot) in them . I dont know if this is your problem but it fixed mine. ps the vac lines I replaced ran back to the dash switch.

[kschoon1]

Thanks for that info - that just may be it. I'm in AZ and dry rot could definitely be an issue. It seems as if this A/C unit doesn't have the shut off valve in the coolant lines. It must just redirect the airflow by clsoing a panel or somethng and that must be where the vacuum lines come in. I'll check it out - thatnks for the info.

[kschoon1]

JDSR - did you just use same diameter lines or did you have to purchase specific replacments?

[jdsr]

Quote:

Originally Posted by kschoon1 JDSR - did you just use same diameter lines or did you have to purchase specific replacments?

I took the old line to a local auto parts store and we matched it up. Old line was plastic but I replaced with rubber. It worked for me. I fought that problem for the longest time. Even had ac guys try to fix it with no luck. Im not sure how I found out about the vac line could cause my problem(probly right here) But It fix mine. Good luck

[depchief]

Looking at the above picture you will note the air intake is located in the engine compartment. When the engine is running, the hot air is sucked into the box and thus tempers the cold air with the hot.
By operating in the MAX air position the cold air circulates in the cabin area and does not draw in the heated air.
It would be nice to add a duct from the air intake down to a lower area to avoid sucking in the heated air.
For the present when you are in traffic run in MAX, on the road you can use Normal

[oemtech]

Quote:

Originally Posted by depchief It would be nice to add a duct from the air intake down to a lower area to avoid sucking in the heated air.

DC,

This is on my project list.

[abarkl]

Quote:

Originally Posted by depchief Looking at the above picture you will note the air intake is located in the engine compartment. When the engine is running, the hot air is sucked into the box and thus tempers the cold air with the hot. By operating in the MAX air position the cold air circulates in the cabin area and does not draw in the heated air. It would be nice to add a duct from the air intake down to a lower area to avoid sucking in the heated air. For the present when you are in traffic run in MAX, on the road you can use Normal

In the Southwest US in the Summer there is no cool air inside the cabin or outside!

[Ding-a-ling]

I, too, learned early on to just change the setting to MAX A/C. Works well for us!

[jdsr]

I was changing to max ac when I was stopped or in traffic untill I found this problem. The hoses looked fine but as soon as I handled them the cracks showed. I couldnt understand how other mhs and veh I drove didnt need to switch to max ac when stopped or in traffic. Since I replaced the hoses I never have to switch to max while stopped now and I live in the south. I dont know , maybe I got lucky. It cost me all of 5.00 to fix mine. good luck with yours