[Mikes7.3]

My ac isn’t blowing cold in the cab, it’s cold going into the evaporator but the hose coming out of the firewall isn’t. Right where the hose hose into the evaporator it’s blowing cold into the engine compartment. Your thoughts please
Freon is correct, compressor is working.

 

[Gnathv]

Do you have good air flow into cab? Does the air come out the vents like it should? Did you put gauges on it and read pressures? Is there any condensate from evaporato?

 

[Mikes7.3]

G

Do you have good air flow into cab? Does the air come out the vents like it should? Did you put gauges on it and read pressures? Is there any condensate from evaporato?

Good air flow in cab.
Air comes out vents.
Yes I used gauges.
Condensation at the point where the orfice line enters the evaporator.
Is it possible that the evaporator is so clogged that air is getting through it and is blowing back through the dog house?
I have over 400,000 miles on this truck.

 

[Gnathv]

If you have good air flow the evaporator should be fairly clean. Do you have condensate on the suction line to the back of your compressor? What were your readings with your gauges?

 

[Mikes7.3]

(Correction) Isn’t getting through it.

If you have good air flow the evaporator should be fairly clean. Do you have condensate on the suction line to the back of your compressor? What were your readings with your gauges?

No condensation at the back of compressor.

low side 30-45
Hi side. Holding pretty consistent 150

 

[Mikes7.3]

(Correction) Isn’t getting through it.

No condensation at the back of compressor.

low side 30-45
Hi side. Holding pretty consistent 150

I’ll try to send a picture of where the condensation and possible leak is coming from shortly.

 

[Mikes7.3]

 

[Mikes7.3]

View attachment 206916
View attachment 206915 View attachment 206915 View attachment 206916

It’s leaking where it goes into the evaporator box

 

[Gnathv]

I think your charge is low, unless it was 65 to 70 the day you checked it. Here is a chart for 134a, look at the outdoor temperature and then look at the pressures you should have. The place where the cold air is leaking out of the evaporator box isn’t unusual. It should have a tape type caulk wrapped around the pipe to seal it. It also looks like that seam isn’t meeting and sealing as well as it could.

 

[Mikes7.3]

Th

I think your charge is low, unless it was 65 to 70 the day you checked it. Here is a chart for 134a, look at the outdoor temperature and then look at the pressures you should have. The place where the cold air is leaking out of the evaporator box isn’t unusual. It should have a tape type caulk wrapped around the pipe to seal it. It also looks like that seam isn’t meeting and sealing as well as it could.

View attachment 206917

Thank You! I’ll add some Freon and let you know.

 

[Gnathv]

Most likely as it reaches the correct pressures you’ll see the condensate creep along the suction hose to the back of the compressor. You’ll also see a healthy condensate drip out of evaporator tube at bottom of box.

 

[Mikes7.3]

That

Most likely as it reaches the correct pressures you’ll see the condensate creep along the suction hose to the back of the compressor. You’ll also see a healthy condensate drip out of evaporator tube at bottom of box.

That did it 50psi low 250psi hi blowing 60* in the cab!
Thank You!!!

 

[Gnathv]

Glad to hear it.

 

[Robbo-9425]

My ac isn’t blowing cold in the cab, it’s cold going into the evaporator but the hose coming out of the firewall isn’t. Right where the hose hose into the evaporator it’s blowing cold into the engine compartment. Your thoughts please
Freon is correct, compressor is working.

I’d still say your evaporator is clogged internally and externally. And did you really get 150 lbs on the high side? That’s the top of the range. Also, 60 degrees is only good if it’s over 95 degrees ambient temps. Which also sounds like the orifice tube is obstructed. But now that you’ve charged it, you may want to change the evaporator, orifice tube and accumulator if it starts malfunctioning again in the near future, rather than mess with it again now.

 

[Mikes7.3]

Temps

I’d still say your evaporator is clogged internally and externally. And did you really get 150 lbs on the high side? That’s the top of the range. Also, 60 degrees is only good if it’s over 95 degrees ambient temps. Which also sounds like the orifice tube is obstructed. But now that you’ve charged it, you may want to change the evaporator, orifice tube and accumulator if it starts malfunctioning again in the near future, rather than mess with it again now.

Temps are below 60* now, not going to do anymore unless I have to for now. Thanks for the information.