So it's about 103 here and my A/C doesn't really cool my truck at all. I actually sweat in my truck sometimes. I have seen at oreillys they have A/C recharge kits. Do those actually work? Is it normal for it not to cool down much in this heat? How hard is it to recharge? What kind would I need? I have no idea where to start. Should I just take it to a dealer?

 

Is the compressor cycling?

 

You don't have to take it to a dealer, but you do need to get the proper amount of freon in the system by a qualified AC tech. I know at some point the system amount was increased for the 03/04 models but I don't know the exact amount anymore. Just "adding a can" could cause you all kinds of (and maybe expensive) problems.

 

So what do you suggest I do. I don't even know any A/C guys. Can they check it at an auto parts store?

 

Ok so from what I found my truck takes 42oz of R-134a and 9oz of PAG-46. What I can't figure out is how to know what to add. All I can find out is how much pressure is in the system, if it's been recharged this way before there might not be any PAG-46 in there and only R-134a. I can't get it back to the right amounts without vacuuming out the system and I don't have the facilities to do that. I'm thinking I'm going to have to take it to a dealer to have it done properly.

 

Here is what I would do:

Turn the a/c on and make sure the compressor is cycling by watching it with the engine running.

If it is, check the freon level by using a gauge on the low side connection of the a/c line. It will only fit on one side.

When the compressor cycles you should see the gauge in the green area or about 35 psi IIRC.

If not then you need to ad freon, using the gauge to guide you.

Keep in mind its very hot today and your air would not be ice cold in most places.

Low freon is the most common problem but definitely not the only one that causes warmer air when the a/c is on.

Good luck

 

I found one of those recharge bottles with the gauge on it, it shows the pressure should be at 50-55 psi in this temperature. What's that all about? Everything I read says 35 but the bottle says 50-55. That's where my concern is. And you wouldn't worry about the PAG-46?

 

Too much freon can shut down the A/C too. It has a high side cut off switch that will stop the compressor in an overcharge situation.

 

You don't have to go to a dealer to get the A/C fixed if all it needs is charging.
If it needs some parts you can still go to a shop that does A/C
You should have the proper tools and the Certifications to go along with it.
Several things can happen and the least of which could non working A/C
The worst a big find from the Men In Black (EPA). But really unless you
do this and know what your doing take it to a A/C shop.

Sean

 

As a general rule of thumb if you get a 20 degree temp difference from the outside temp to what is coming out the vents your system is running efficiently. Purchase one of those little pocket thermometers and stick it in the vent. Dont forget to clean the A/C coils dirt and grime can affect the operation(the radiator no pressure washer it will bend the fins). The system is designed to be closed, but we all know what that means, seals and things begin to leak. I have been adding a lb of refrigerant to a system for years, works great. Yes you can have other problems but many times it is a slow leak, get a can add a little many YOUTUBE videos watch your temps inside if you get it down to about a 20 degree difference not bad...........don't be scared

 

correct amount with out running outside and looking is like 0.77kg

 

Pressure/ ambient temp./ humidity charts were developed for a reason as were hi/lo manifold gauges. Slug a compressor and you'll wish you'd taken it to someone that knows what they're doing. A slugged compressor has also been known to take out belts.

 

The pressure is higher with the temperature.

 

Came across this nice little write up.

Air Conditioning Temperature Basics