A/C not blowing cold air

Hi,

When you check it with the engine off and the gauge is at max, what is the high pressure side pressure? Is it high or low?

If the low side is too high and the high side is low, chances are the compressor is going bad. If both sides are too high, it's over charged.

The pressure shouldn't really change when you refit the connector, so we need to figure that one out.

When you have it running and it shows 29 - 39 psi, I need to know what the high side pressure is. Also, the outside temperature plays a role in this as well. The pressures (29-39) are normal low pressures for temps between 65°F and 80°F. So I will need to know what the temp is when checked.

Here is a link that explains how to vacuum and recharge the system. I'm adding it because it discusses the AC manifold gauges that will be needed.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

I hope what I said makes sense. LOL I started rambling.

Let me know.

Joe

Hi Joe, thank you for replying.the psi I got was using the recharge gun gauge I don’t have the twin gauge set yet trying on eBay but no connectors so waiting reply from seller. The temperature outside was 98f with recharge on low psi line , I suppose I will have to get the gauges to check both psi as you say.

Hi,

The low pressure at that temperature should be around 55 psi. So, it was low, but I'm not sure why it would change when you disconnect and reconnect it.

If I know the high pressure side info along with the low side, I will have a better chance to determine what is happening.

Let me know if you get the gauges. If you can't, let me know and we'll try to figure another way to check.

Take care,
Joe

Hi Joe, ordered gauges. can walk in and buy them anywhere? should have them this coming Thursday; I’m off work then so will be able to see what I can do then. thanks again for you help.

Hi,

You are very welcome. I hope I can help you resolve this. Hopefully, the readings will provide the info I need. I'll watch for your reply.

Take care,
Joe

Hi Joe,

Gauges came today I have connected them and taken a static reading just now , it’s 21.00 here.
The result is:
High pressure gauge 62 psi.
Low is 71 psi.
Temperature is 90f.
Yep I know 90f England 21.00.hours..
I don’t have vacuum gauge so can I carry on and get more info oh this car has an expansion valve I see they can block up or stop allowing flow of gasses?

Wow! Based on that, I think the compressor is bad. What are the pressures with the engine running?

Joe

So not long in from a 20 mile trip home from work, I have connected gauges up and found the following:

Static hot engine air con not been switched on.
Low 80 psi High 70psi .
Air con switched on fan on full power and compressor clutch engaged,
Low 30psi. High 130psi.
Temperature of hoses from compressor Low 162f. High 163f both rising slowly condenser temperature taken on front 91f .
My coolant cooling fan was not running at a high speed although it was cooling the engine sufficiently on the way home , oh yes the air temperature is approx 96f at present, thanks so much could any of this be due to not vacuuming the system before I gassed it up it had been idle as condenser was u/s, or am I clutching at straws haha. thanks Joe.
Loads of pre owned compressors on eBay but can I trust them don’t want to buy one in same condition as mine.

Was the outside temperature when checked below 70°F? If it wasn't, it sounds like it is low on Freon. Let me know the outside temperature.

Joe

Hi Joe, did what you said and gassed it up again and I have A/C.
Just got back from GP visit cold all the way home thank you so much I was going to ring a garage to evacuate the gas and vacuum it. you have saved me a load of cash thank you very much.

Great, and you are very welcome. I'm glad to hear it's working for you.

Take care and feel free to come back anytime you have questions.

Joe