Think I blew out my AC today..

Grabbed two refill cans because I was low, put one in and still wasn't up to where I wanted, loaded up the second and about halfway through it started blowing gas from under the truck. Multiple times. I feel like an idiot. Anyone know how much damage I might have done? AC is blowing warmer than before the refill

Thanks,
Tamer

 

who needs ac anyhow

 

You probably over filled it. There is a pressure relief valve on the compressor that opens when there is too much pressure in the system to protect the components. i.e. overfilling or if there is blockage in the lines.

You need to take your truck to a mechanic asap if you want your a/c to work.

 

This.

Most likely, you've blown an o-ring.

Do NOT run the compressor until it is fixed.
At this point, you might be able to get away with $150 or so for a system check and o-ring replacement, system purge, evacuation, and recharge.

Run the compressor and you might be in for $1200 or more.

You may already be there if you blew the compressor's front seal.



It's hot.
It's humid.

Auto AC, especially R134a, will NOT blow "ice cold" when it's 100 degrees at 50% humidity.
There was likely nothing wrong with your AC to begin with.

 

That was quick. Thanks guys, I'll take it in tomorrow and see what he says.

 

I was hoping there would be a relief valve that was letting it go, but sounds like that's not the case..

 

Yes, it could well be the relief valve. I have seen that one before.... "Multiple times" will happen as the compressor cycles on and off and lifts the relief valve. This usually causes no damage but you really need to get the charge dialed in correctly.

 

You can't just throw R134 in, there is no way of telling if it full or not with out gauges. Yes there is a over pressure valve you may have lucked out.

 

I got lucky. It is supposed to have 1.3lbs in it, and it had 1.9lbs, but no damage was done. The dealer unloaded it down to spec and all is well. The idiot mistake cost me $189 My normal mechanic wouldn't touch it because I used the stop leak stuff.

Anyways, the mistake I made was reading the pressure when it was running. He explained that I need to read the pressure with the system and engine off not running.

 

no the mistake you made was messing with it at all, you do not have the proper equipment to do a evac/vacuum/refill... and those cans are garbage...

 

The stop leak is garbage, which does more harm than good. The cans without the stop leak are fine, but you have to know what you are doing. As stated before, adding Suva to an already full system is not good for it. Gauges are inexpensive, knowledge on how to use them is easy to find, but leak detectors and evacuators are expensive...

 

That is not true.

The pressure needs to be read while running, but what matters is the balance between the low side and the high side, as well as the temperature of the air moving through the condenser.

Ambient temperature will impact the pressures in the system, as well as the balance.


But more importantly, PRESSURE is not the only factor. What is critical is the quantity. You can get 45psi in the system, and MIGHT even show the the correct pressures on both the low side and high side, but have too little refrigerant in the system.
The quantity of oil is equally important.

This is why DIY recharge kits are not a good idea.
They don't tell you the balance.
They don't tell you the liquid levels.

They just give you low side pressure.

 

Can anybody tell me the proper operating pressure for both the Low and High side. What the readings should be? I have read that low should be 25 to 40 PSI and the high 225 to 250 PSI. Is that right? thanks!

 

Low side is good at 25 to 40.
Ballpark for the high side is to multiply ambient temperature by 2 and add 50, so at 80 degrees ambient, a good high side will be around 210... but that is only a rule of thumb.

Also a rule of thumb, low side pressure plus 5 will be close to the evaporator temperature when in the 0 to 50 degree range.
It's a curve with there being a bigger difference when colder, and the numbers cross where 70 low side is roughly 70 degrees, and above there, pressure climbs away from temperature (300psi is roughly 160^f).

But.... Ambient temperature matters. A low side pressure of 30psi at 65 degrees ambient would be closer to 50psi at 85 degrees.


According to Arizona Mobil Air, you can expect to see:
http://www.ackits.com/aacf/ptchart.cfm
16-29psi = Evaporator 33-50^f = high side 115-200psi = ambient temp 70-80
19-39psi = Evaporator 33-60^f = high side 140-235psi = ambient temp 80-90
25-43psi = Evaporator 40-65^f = high side 165-270psi = ambient temp 90-100
37-51psi = Evaporator 48-65^f = high side 210-310psi = ambient temp 100-110

Measure ambient temp 2" in front of the condensor and work backwards from there... If it's 80 degrees, you're looking for a high side of 115-200, low side of 16-29, and evaporator temp of 33-50^f
Given the range 70-80 for those pressures, at 80 you'd expect to see the numbers in the higher end.... more of a balance between the 70-80 and the 80-90 numbers.

If the numbers don't add up... you're over 235 high side and under 19 low side, and the evaporator is 60, then you likely have an issue with the volume not being correct... or a part of the condensor or evaporator is not working.

 

Thanks man! I am checking mine tommorrow and needed some numbers, I live in GA and we been having 90+ degree days here. I will check what the temp it is tomorrow when I do it to make sure I get a good balance.

 

You really need to have a big fan blowing air over the condenser and the a/c set on recirc with the inside fan on high. Also be aware that the pressures change a lot when the engine revs. Highs will go up and lows down as the compressor does more work. Just taking pressure readings at idle with little or no air flow over the condenser and evap tells you very little.

 

Thus the HUGE expanse of "expected" pressures for each given temperature.

It really is not a DIY job unless you've got the experience to know what to expect.

 

I kinda chucked when I read TWO cans of refill LOL