ac check valve

[Ramster]

I looked at the elect. coolant valve as suggested on this forum and it helped with the A/C, the valve was stuck open so hot water was going in, thanks, air blows colder now. The problem is still is going on with the air shutting off under load and going to defrost.

I talked to a a/c guy and he says to look at the check valve on the engine does anyone know where this is? any pics?

If that does not fix it then I guess I look at the vacume canister right?
Thank you

[ValleyCenter]

I was told my electric heater box valve (some call it other names, allows hot water into heater box) was bad and needed to be replaced. I got to looking at it this morning, run some simple tests, and found the hose coming from engine is going direct to heater box. the out hose from the heater box goes to the electric value then returns to engine. this is backwards. it's allowing hot water to enter the heater box even when the AC is running. Granted it's now flowing but still driving in the heat. I talked to a mechanic friend this morning and he confirms the hose from engine should go to valve ahead of the heater box, not the other way around as mine is currently configured. Will re-plumb hoses next week. As for the AC turning off when you drive it may not actually be a problem but a sensor in the engine will turn AC off when the load exceeds a certain amount thus keep the engine from overheating/overload. what type engine do you have? Mine ford V-10. Does the AC stop and convert to defrost sound when your going up hill? On straight away it's fine? If so, like what I explained is happening. going up hill, turn on the fans and the roof ac with gen.

[Ramster]

ValleyCenter... the air does divert to the defrost.

I am in contact with Evens Tempcon to replace the elect. valve your talking about. Mine was stuck open some and hot water was coming through, the air was not as hot as should be.

I took off the elect. valve from Evens myself (easy to do) put on a manual valve for $13.00. Works fine now the new elect. valve is $169.00 with a new wire harness and adaptor for it!!

I asked the board about this air fix, do a search on my post, there is a vacume problem with the air going to defrost. Evens sent me a fix from ford they say the are to blame?

P.M me i'll send it to you

Mine is a V10

[ValleyCenter]

still trying to figure out how to do PM. A copy of what you indicated would be much appreciated. On the AC electric valve could you take a look at your hose plumbing and verify the "Hot water In" hose coming from the engine is going direct to the valve or heater box? On mine it's going to the heater box and I'm certain that is wrong configuration, on mine. The electric value is plumbed after the heater box and on return hose to engine. My value works fine since the hose on the "out side", return to engine is cold while the hose going into valve is hot.

[George Z]

I believe the airflow changing to defrost is due to a lack of vacuum. The air flow flaps are usually vacuum operated and the default due to a vacuum leak is defroster air. You might check for a disconnected vacuum line or a leaking hose. Also we installed a 1/2 inch brass ball valve in the heater supply line that we just turn off when in an area where we will not need heat.

[ga traveler]

George Z is right. your defroster is spring loaded to the defrost position. This is for safety. If you are pulling a hill and lose vacuum your windshield will stay clear. Check for a vacuum leak. If no leaks you can install a larger vacuum canister. Make sure you check the old canister, they are plastic and tend to crack.

[Ramster]

Valley if you want to P.M. you click on the name Ramster or anyones name that has posted click and you'll see send a private mess. click there and follow instructions.

Can anyone tell me how to get to vac canister?

[ga traveler]

Quote:

Originally Posted by Ramster Valley if you want to P.M. you click on the name Ramster or anyones name that has posted click and you'll see send a private mess. click there and follow instructions. Can anyone tell me how to get to vac canister?

The easiest way is start at the intake manifold. Find a rubber hose about 3/8 of an inch. It will be larger than most. Follow it till you get to the cannister. It will go forward, toward the radiator.