Hot air coming out of the A/C...Compressor, hot/cold door or leak?

[Boost N Juice]

I've searched for "A/C heat" and "A/C hot" but still need more info...

Upon several searches, it says to see if the compressor cycles normal...I checked and this is how it cycles, it turns on for a half second, stays off for three seconds and keeps doing that...Is that normal? I'm told to check the wire on the hot/cold door...Is there a how to for this? I'm not sure how to get access to the back of the HVAC controls nor what to do when I access it...

 

[BBQ_HotDogs]

Boost Ur Juice, you need to look for the flap door issue. It's not your A/C. This was a very common issue with Explorers. It's not called the flap door though, but right now I can't think of the correct wording. I think Blend Door. It is under the dash and a pain in the rear to fix. I had the same issue, but under warranty. It took them 2 tries to get it right.

 

[BBQ_HotDogs]

Here is a link. http://userwww.sfsu.edu/~dmf/blenddoor.htm You can also hit the search feature and type in blend door and come up with a thousand others just like you.

 

[Boost N Juice]

Thanks for the info...I wasn't sure if my compressor was cycling normally or not...

Is there a test I can do to see if the blend door is the problem?

 

[BBQ_HotDogs]

You will have to read up on it. But if I remember correctly, with the A/C on and blowing hot air, touch the A/C lines and if they are cool, then it is more than likely your blend door. This is a very common problem with the 2nd gens.

 

[Bob K]

A/C hot - would be more helpful if you stated the air temp coming from the center register with A/C Max and fan speed high.

When you switch from A/C Max to A/C the blend door will open to let in outside air. A/C Max operates with recirculating the cabin air. The noise is the vacuum release of the blend door. If you don't hear a noise, then chances are you have a blend door problem, but could be other things as well.

Checking refrigerant lines will also help confirm wanted thought you should have more information to pinpoint problem.

 

[Glacier991]

Cycling that rapidly in warm weather strongly suggests you have a low charge. Before you go suspecting the blend door, you should make sure you have a full charge of refrigerant. That is a higher probability as the culprit than the blend door IMHO.

 

[wingot]

compressor should stay on longer than a second...

 

[Boost N Juice]

Great info, looks like I need to do some tests after work...

What is the normal cycle? XX seconds on and XX seconds off?

 

[Glacier991]

Actually the cycle will vary depending on ambient temperature, cabin temperature, engine RPM etc... but as a general rule (as if there IS one) 1- 2 cycles per minute at normal summer time temps, and the cabin cooled to about 75 degrees, engine at about 1500 rpm.

 

[Boost N Juice]

Check what I could, I hear the vacuum noise when switching from A/C to Max A/C...

I don't know much about an A/C compressor, but it doesn't seem like it's engaging, it just kinda clicks for that half second...Anyone now how I can see if I'm low on refrigerant? Also, does the engine need to warmed up in order the A/C line to feel cold? Or can I start the car, put the A/C on, and if it's working, the lines should be cold right away?

 

[Glacier991]

based on what I'm hearing, I'd advise you to take it in to an AC shop and have them check the charge and add refrigerant if necessary (betting 10-1 it is).

 

[monkeydude3]

sounds like you are low on charge. May as well have them leak test it while they are at it.

From my experiences it is normal to need maybe one can of refridgerant per year. This accounts for the winter and constant change in temperature and movement of all the a/c fittings. These are bound to leak, because they are only snap in connectors with O rings. Charge it up (make sure they put in about 6 ounces of a/c compressor oil WITH the coolant) and see what that yields.

This will allow your compressor to stay on longer, thus giving ocnsiderably more cool air.


George

P.S. I took and passed the ASE A7 heating/air conditioning test. I've also diagnosed and repaired pretty much every a/c leak that has sprung on my 1994 exploder. Done a good deal of other diagnosing too.

 

[Boost N Juice]

Cool...I just didn't want to pay the A/C service if that wasn't the problem...Thanks...

 

[mckenzieslayer]

I agree it is "short cycling" - due to low pressure
throw a can in

 

[Boost N Juice]

Got the $25 134a DIY kit and it made the AC cold...Hopefully, it's lasts for a while/not a major leak...