ac not cold enough
 

i have a 70 c-10 and the ac blows just cold enough to keep you from sweating. the system has a full charge. where should i start first

Re: ac not cold enough
 

Check your heater shutoff valve. If it is not closed when the A/C is on, the heater core will get hot, and work against the A/C.

Re: ac not cold enough
 

Make sure that your heater valve is working and is cutting off the flow of coolant to the heater core. This will cause the air to be heated.

Re: ac not cold enough
 

the heater hoses are not hooked up

Re: ac not cold enough
 

So check to see if the door in the unit is moving all the way and sealing.Another cause could be debris in the ductwork.

Re: ac not cold enough
 

Check your cowl fresh air vent (under the hood, passenger side firewall) to make sure it is closed when the A/C is on. I will bet this is your problem. If it is open, it is allowing outside air to mix in, and thus robbing you of cold air. Also check to see that the recirc vent (in the cab on the pass side kick panel) is open when the A/C is on, or you will have a huge loss of airflow

Re: ac not cold enough
 

Couple of questions: Has it worked before? And is it an original A/C truck with the old compressor?

Many years ago, I fought a similar problem on another vehicle. Finally, I got tired of messing with it and bought a new compressor and that took care of the problem.

If your compressor is old it may be that it's just not working effeciently. I'd check all of the things mentioned and then you may have to bite the bullet and go the whole way.

Re: ac not cold enough
 

If all of the above checks out,feel the return line going towards the compressor.It should be very cool (40-50 deg.) . If not you could have an overcharge condition or other problems,such as a stuck expansion valve,restricted screen,or maybe the "power element bulb" is loose in it's fit against the evap.outlet tube.The entire length of the of the bulb must me in tight contact or you will get poor cooling.

Re: ac not cold enough
 

You might want to wash out the evaporator in the fiberglass housing under the hood. I,ve seen em real dirty this will not cool as good. Did you measure your refridgerant with a scale when charging system

Re: ac not cold enough
 

thanks for all the replies. i want be able to check everything until sunday. i will post after that.

Re: ac not cold enough
 

What are your refrigerant pressures on the high and low side? Is it still R-12?
By the way, Welcome!

Re: ac not cold enough
 

the recirc vent is open. ac has been converted to 134, lowside has 50 psi, how can i tell if the cowl fresh air vent is closed, any pics would be appreciated, thanks

Re: ac not cold enough
 

Look underneath the cowl on the passenger side. The door is controlled by an actuator on the firewall (you will see the setup when you pop the hood) You might need a flashlight to see it in the cowl.

I am at work, and don't have a camera or pic, but I am sure someone else will post one if needed.

Re: ac not cold enough
 

when u look at it through the cowl it appears to be flat, when i press the actuator it puts it at 45 degree angle, so with it being flat is this the closed position

Re: ac not cold enough
 

yes, that is correct. it needs to be closed when the A/C is on. check to make sure that is the case with the truck running, and a/c on. if that is functioning properly, you could have some dirt/debris in the evap case housing, or an expansion valve problem as described above.

Re: ac not cold enough
 

ok F.a.v. is closed with ac on and truck running. what do i need to do to clean evap. also how much is a expansion valve. thanks