A/C refrigerant too high?

[Ericsch83]

So, anytime I turn my AC on the engine rpm's get low, and the a/c compressor clicks off and on, so I figured it was because my refig. was too low. So I got a can of refig. that has a guage on it. I connected it up and the guage was in the red danger zone saying that I had too much psi? any thoughts?

 

[GoodysGotaCuda]

Was the engine running when you were looking at the gauge? how much psi are we talking? Assuming you were on the low side as well...

 

[pacodiablo]

There are low and high pressure lines. You are supposed to add to the low pressure one. Are you sure you were adding to the low pressure fitting?

 

[GoodysGotaCuda]

There are low and high pressure lines. You are supposed to add to the low pressure one. Are you sure you were adding to the low pressure fitting?

They are two different sizes. Can't really get the low side fitting on the high side. If you do, thats impressive

 

[LittleHorse]

What was the actual psig reading on the gauge?

 

[Ranger44]

As previously mentioned, on R134A systems the low and high sides are different sizes. Can't really be confused.

Those cans aren't the best at all, and to properly add refrigerant you need a manifold set that has actual gauges on it.

If the compressor is cycling on and off rapidly it can mean there is a blockage some where and the pressure switch keeps cycling the compressor off, or there's not enough refrigerant in the system and the other switch keeps cycling the compressor off to save the compressor from burning up. Now.....those cheapo cans/gauge sets are not reliable for an accurate reading, but showing a red reading may tell you that the pressure is way to high and may have a blockage of some sort.

If indeed the refrigerant is low, you need to find out why its low. It just doesn't evaporate. Did you try to add it when the vehicle was running or off?

 

[4x4junkie]

It's normal to lose maybe an ounce or so of 134A a year due to permeation through the rubber hoses & seals.

But yes, you should get a proper set of gauges on there and see what's going on with it. Those stupid little gauges attached to refill cans don't really tell you anything useful at all, even if it were reading "normally".