AC blowing hot

Reply Subscribe

Thread Tools

Search this Thread

Jul 20, 2003 | 05:21 PM

jaim979

Thread Starter

New User

Joined: Jul 2003

Posts: 2

Likes: 0

AC blowing hot

The air conditioning on my '91 F250 diesel is blowing hot. I usually rely on my dad for help with this, but he's out of town and it's 115 degrees here! Help!!

Something was recently replaced with the AC (it wasn't blowing air at all a few months ago), and it worked fine for a few weeks. I'm not sure what was replaced. Yesterday the air started switching from hot to cold to hot, and by last night it was completely gone.

I don't know a ton, but I know some and would like to be able to fix this or at least know what's going on so that I don't get taken advantage of if I have to take it somewhere. Any help anyone could give would be most appreciated.

Thanks!

Jul 20, 2003 | 06:03 PM

94van

Posting Guru

Joined: Oct 2000

Posts: 1,577

Likes: 0

From: Southern MD

AC blowing hot

First thing ya gotta do, is put a set of gauges on and see if there is any refrigerant in the system. That's your starting point.

Jul 20, 2003 | 06:09 PM

GR8Diesel

Senior User

Joined: Jun 2003

Posts: 439

Likes: 0

From: Burnsville, MN

AC blowing hot

You could look to see if the compressor is engaged, if not it could need recharging.

If so, is the smaller of the two lines going into the firewall / heater unit warmer than the large one?
If so, some cooling is taking place.

Is the large one really cool?
Probably the mixer door in the heater is bad or not receiving a good vacuum source.

That is about as far as I can go on this...