A/C Question....Need Help please

[FHP89LX]

I had some a/c work done to the explorer. It blows ice cold. The only thing thats wrong is when I am on the highway less and less air blows from the vents. Then I put the a/c to high and still blows very little from the vents. When I get to a dead stop it still blows very little on high. I usually have to wait about 20 minutes for it to work correctly again. City driving is fine, but when I go high speeds in the highway that's when it blows very little air. I checked around for any broken vacaum lines and did not find any. Does anyone know what can cause this?

 

[Jason94sport]

I have a simlar issue but only when the AC is on a long time like 2 straight hours. I hit max AC & full fan & I hear it, but little air comes out.

 

[Maniak]

If the AC has been on a while, and the fan is still going, but no air is coming out.. You froze your condensor.. its not a block of ice.. As I understand it, the A/C is supposed to cycle the compressor so that doesn't happen.. On our '92 it doesn't cycle and if I leave it on low fan but max a/c for a while (few hours) it will freeze up. To unfreeze it, I switch it from max a/c to panel and turn off the a/c for a few minutes.. It doesn't take long for it to unfreeze.. and the air is still cold as it comes in since it is blowing across a block of ice.

~Mark

 

[Longjohn119]

Maniak is most likely correct except it's the evaporator coil that freezes up not the condensor coil which is in front of the radiator

 

[Maniak]

yea.. thats what I meant.. I seem to get the names backwards 50% of the time.

~Mark

 

[vrytired]

as was said your evaporator is freezing. this is caused by low Lo side pressure. a bum clutch cycle switch can cause this or a low system charge.

 

[FHP89LX]

So you think I should change the switch? This is weired because I just came back from a road trip from Miami, Florida to New York and back. By the time I got back by central florida, thats when It started to happen.

 

[Jason94sport]

Low charge hey? It blows cold. Doesn't happen alot, only sometimes with mine. I do think my compressor might be going though. I sometimes have a burning smell from the AC. Could that mean the compressor is frying?

 

[Lynnrb]

So you think I should change the switch? This is weired because I just came back from a road trip from Miami, Florida to New York and back. By the time I got back by central florida, thats when It started to happen.

The switch is adjustable, it needs to be set to cycle off at appox 30# at the low side. Higher humidity in Florida is why it only happen there. A low charge
will cause the system to cycle more often which will allow the ice to melt,
the problem is not low charge.

 

[FHP89LX]

Thanks guys, I will look into that