Low pressure ac switch location

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1BADI5

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I replaced my low psi switch on Friday......not the compressor is working correctly. I think its time to get the R34 evac'd and replaced.
 

TheBigDirty

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Ok so to summarize....

A freezing evaporator can be caused by several different conditions.
A) Inoperable blower motor
B) Clogged filter or clogged coil
C) restriction in the metering device
E) low freon charge
F) improper compressor cycling

There is no low suction pressure cutout on the tahoe, only a low system pressure cutout.

If system charge has been verified to be correct, hi & low pressure's are within range (before the evap coil is frozen) there is plenty of air moving across the evaporator....

The culprit appears to be a faulty evaporator temperature sensor. Apparently this sensor is prone to failure and determines the cycling rate of the compressor to keep the discharge air a constant temperature dependent upon blower speed and temp of air entering the coil.

In the OP's case, it sounds as though, given all system components check out, that the evap temp sensor is keeping the compressor running too long and causing the evap coil to freeze up, because its simply running the compressor too long.

In my case, I feel as though its satisfying pre maturely therefore the discharge air is coldish but not ice cold. I still need to do verify my system charge with real pressure gauges, but Im fairly certain it's fine. I dont think my orifice is clogged, because the line becomes cold and sweaty directly after it but this will be confirmed when I get some real hi/low gauges on it.

Feel free to tell me if im way off on this one.
 

TheBigDirty

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Trying to find information on the location of the low pressure ac switch for the 2011 Chevy Tahoe. Suspect it needs to be replaced but can’t locate it.

I looked up the evap temp sensor,
found it on Amazon for $24 & the best part is.... almost all reviews said it fixed their evap freezing prob

Part number 15-51267
 
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Cjherndon

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Thanks BigDirty for posting that. I assumed my evap temp sensor was the culprit. My next question is...anyway to replace this part without pulling the dash and steering col out?
 

kbuskill

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Found a pic in my phone of my low pressure switch on my '08 Burb. Mine is on the accumulator...

rps20200727_195533_115.jpg
 

TheBigDirty

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Thanks BigDirty for posting that. I assumed my evap temp sensor was the culprit. My next question is...anyway to replace this part without pulling the dash and steering col out?

There is one video on youtube. But other reviewers have described a similiar method...

Removing the air bag to get to the connector, and cutting a hole somewhere in the evap box, top or bottom, dealers choice, to fish the new one in place, then plugging or patching the hole
 

Indy1K

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So, I am dealing with Evaporator Freeze up on my 2007 Tahoe. There has been discussion that the Evaporator Temp Sensor is the culprit. I cannot find any reference to this sensor for the 2007 Tahoe. It appears to be available for 2008 and up.
Can someone tell me if there is an Evap Temp sensor on the 2007 Tahoe that controls the compressor cycling?
People are saying it is the LP sensor that controls the compressor clutch. I dont think that would be the case on a fully charged system.

Thanks ahead of time.

Kevin
2007 Tahoe LTZ
2002 and 2008 Avalanche
 

cbb468

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I have 2016 gmc yukon denali 6.2 liter. I dont see the location of the low pressure switch. Any help i dont see the dryer on the firewall either.
 
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