Is my AC cold enough?
- Thread starter Jonas
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if one of the high speed relays is bad, it would stop that fan dead. One wouldn't get a ground, the other wouldn't get 12V
I really don't know anything about your car, so don't take any of this as gospel. But that's how it worked on other cars with 2 fans and 3 relays.
if it would cause the compressor to cut out too soon, that would impact vent temps at low speeds yes.
Well, more good news. The manifold gauge set I borrowed from Auto Zone didn't work. I hooked everything up, kept the top valves closed, and opened the couplers. The low side went up, but the high side read 0. Now I'm lower on refrigerant and I can't get a reading.
FWIW, the AC on recirculate in my '02 Silverado blows 39°F at the vents regardless of outside temp. Creeps up to mid-high 40's if it sits idling long enough. 207K miles on the original components.
Usually when the air temps won't maintain while idling, it could be simply a sign of a less than efficient compressor. How the age/mileage of said vehicle?
Usually when the air temps won't maintain while idling, it could be simply a sign of a less than efficient compressor. How the age/mileage of said vehicle?
The car is the car is 12 years old with a hundred ninety thousand miles. However, air compressor is 2 months old.
Compressor. Sorry voice to text
What else was replaced with the compressor? And why was the old compressor replaced?
JHZR2
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I’ve always read that 38F is the right temp. I don’t know that I’ve ever seen it in testing. Too many variables related to the ambient conditions, the humidity, airflow obverse the condenser, etc.
X2. If the old compressor grenades and packed the condenser with shrapnel it won't ever cool right. In today's cars the condenser is considered a throw away if the compressor failed.
Interestingly, the compressor didn't fail while running-I don't think. The AC worked all last year and then I had the engine rebuilt over the winter. When I tried to charge the AC, the compressor would not turn on-I don't think. The car idled up when it built up enough pressure, but the compressor didn't compress anything. Low and high side were the same. So maybe I'm okay? Maybe it just seized or was already seized from being out in the open so long with no oil.
When a compressor fails. Be it just worn out or complete destruction the wear parts go directly into the condenser and plug or partially plug it up.
Would that explain my symptoms? 8-10 degrees warmer at idle, vs driving. Also very ambient temperature dependent-The hotter it gets outside, the warmer the AC gets? It will get down to 40 and below easily if it's 80 or below outside.
A
Actually, that makes sense because the condenser removes heat. But, does this apply to compressors that have a control valve and shut off when there's something wrong? My mechanic mentioned "cleaning" everything, but he also said he didn't know why it wasn't very cold. smh.
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*update*
Well, it turns out my belt is slipping. It was making a hissing noise, rather than a squeal, so I didn't notice. I sprayed some belt dressing on it and it started hissing louder, then quieted back down. That might also explain my intermittent low alternator voltage. If that was the problem all along, I'm going to be happy and angry lol.
Well, it turns out my belt is slipping. It was making a hissing noise, rather than a squeal, so I didn't notice. I sprayed some belt dressing on it and it started hissing louder, then quieted back down. That might also explain my intermittent low alternator voltage. If that was the problem all along, I'm going to be happy and angry lol.
A clogged or partially clogged condenser can absolutely cause cooling issues and do you know if the orifice tube or whatever metering device that is used on your car was replaced?
It's a thermal expansion valve and no, it was not replaced. I don't know how to tell if the condenser is clogged, but it would make sense since more airflow makes such a dramatic difference in cooling.
Here are my pressure numbers from this morning:
80 degrees outside, doors/windows open, max recirculate, fan medium high:
Static: low side-64, high side-122
Idle: Low-27 to 34, high-170 to 190
1800 RPM: Low-22 to 25, high-200-210
Vent temperature at idle: 51 degrees
Vent temperature at 1800 RPM: 46 degrees
Your static pressures seem off. Both sides should be close to the outside ambient temp if your charge is correct. That was taken with the gauges hooked up and the car off?
For testing purposes your blower motor should be set on high. Your high side pressures seem pretty good given the outside ambient temp. The low side may be a little low but maybe not for your system.
I would definitely think you would be getting higher vent temps at idle. Are you checking the vent closest to the evaporator?
For testing purposes your blower motor should be set on high. Your high side pressures seem pretty good given the outside ambient temp. The low side may be a little low but maybe not for your system.
I would definitely think you would be getting higher vent temps at idle. Are you checking the vent closest to the evaporator?
I just arbitrarily listed the static pressure. It was taken shortly after the car was shut off, so I guess the pressures hadn't equalized yet?
Someone from another forum suggested the blower be on medium high-I don't know why.
Higher vent temps at idle? 51 degrees at 80 ambient seems pretty weak to me. It was technically the second closest vent, but both the center vents read about the same temperature. One outer vent by the window has good airflow and reads about 2 degrees warmer, but the one on the other side, hardly any air comes out. I haven't checked the temp on that one, I just keep it closed.
I should add that later during a trip on the interstate, it was 85 and sunny-the center vent read 38 degrees (recirculate/medium high fan)
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I meant to say lower vent temps at idle. LOL 38 degrees seems pretty good going down the road.
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