Air condition in the Ford motorhome

[Karl06greyhawk]

When I'm pushing the gas while driving my motorhome my ac quits blowing air when I let off it blows just fine why is this ?? It never use to do this could it be low in freon ??

[Robbbyr]

Originally Posted by Karl06greyhawk

When I'm pushing the gas while driving my motorhome my ac quits blowing air when I let off it blows just fine why is this ?? It never use to do this could it be low in freon ??

Does it instead blow air out of the defroster outlets for a bit? Many Fords use engine vacuum to operate the different "doors" in HVAC system, defrost is usually where they fail to when vacuum is low or gone.

There usually is a vacuum reservoir that stores vacuum to "hold" the settings when the throttle is open wider (climbing hills) and vacuum drops off. A check valve holds vacuum in the system when engine vacuum is low. Two things I suspect are a possible vacuum reservoir or check valve problem.

[Karl06greyhawk]

Originally Posted by Robbbyr

Does it instead blow air out of the defroster outlets for a bit? Many Fords use engine vacuum to operate the different "doors" in HVAC system, defrost is usually where they fail to when vacuum is low or gone.

There usually is a vacuum reservoir that stores vacuum to "hold" the settings when the throttle is open wider (climbing hills) and vacuum drops off. A check valve holds vacuum in the system when engine vacuum is low. Two things I suspect are a possible vacuum reservoir or check valve problem.

Yes sir this is exactly what is happening so I am assuming it's a vacuum problem or valve thanks

[Robbbyr]

Originally Posted by Karl06greyhawk

Yes sir this is exactly what is happening so I am assuming it's a vacuum problem or valve thanks

If a leaky reservoir or cracked hose you migt be able hear a "hissing" at idle. If a bad check valve you won't hear anything leaking, it just doesn't "hold" it anymore. Sorry I can't give you more specific troubleshooting ideas.

[TWP723]

I think Robbbyr may be right. On top of the evaporator case is a oblong reservoir and a check valve in line with it. We sell both on a normal basis. I'd check them. Relatively cheap.


reservoir-$41
valve-$8