A/C problem, done for the winter, need advice

I've been dealing with an A/C issue for the last few months. The compressor is cycling about every 10 seconds. I've had the system evacuated and recharged, replaced the compressor, compressor speed sensor and wiring harness. I've taken it to an automotive a/c "specialist" and was told nothing is wrong. I've checked periodically with a gauge manifold and confirmed there is a leak somewhere because the static pressure drops continually over time. But I just haven't found it yet. I'm afraid it's somewhere behind the dash, maybe the evaporator. Frankly, I'm sick of it at this point and need to take a break for a while. Plus, I live in the northeast, so working a/c is needless worry for about the next 7 months. I have read endless threads about rapidly cycling compressors and potential causes, so I'm not necessarily looking for troubleshooting advice, though it's welcome and appreciated.

So, on to the point of my post: I was thinking about just unplugging the binary switch on the high pressure line to prevent the compressor from constantly cycling (and wearing out the clutch) when I'm using the defroster this winter. Is this a bad idea? Would doing this cause any issues elsewhere in the system? My thoughts are it would simply (and harmlessly) disable the compressor.

Also, if I were to do this with no negative effects, does anyone know where I could get covers for the electrical connectors? (see picture)

Thanks in advance!

 

Did the same thing for well over a decade on my 2.2 Sonoma. [yeah yeah, GMC but was 100% reliable and a great cheapo winter truck with no frame rust issues for the 13 years I owned it]. Defrost won't work as fast but other then that, every summer I plugged it back in and it worked as intended.

The only time A/C works on heat mode is on the defrost setting where most will just cycle on and off to remove moisture from the inside of the vehicle.

 

did you have dye added to help find the leak?

 

Yes, the "specialist" added it during a recharge. It showed up on the underside of the compressor, so I replaced that along with the speed sensor and wiring harness on the advice of the shop. There are no other signs of the dye at the condenser (replaced during a frame swap last year), lines or high/low pressure ports. I removed the fan assembly under the dash and as near as I can tell there is no sign of dye there either. But, I'd have to pull the dash to be sure and I'm just not ready to do that. It's also possible the binary pressures switch is faulty, or there may be a very slow leak in one of the schrader valves. It's enough to make a person go insane!

 

This thread is useless without high side pressure, lowside pressure, ambient air temp, and duct temp.

 

High: 245 psi/Low: 39 psi at 2000rpm
Ambient temp: 82F
Relative humidity: 80%
Duct temp with blend door closed: 55F
Compressor cycling every 11-12 seconds.

The thread isn't useless, I just wanted to know if unplugging the pressure switch would cause any problems.

 

No, leaving the pressure switch unplugged won't harm anything. Dunno why you want to unplug it though; if you have a slow leak, eventually there won't be enough refrigerant left in the system to close the contacts on that switch anyway, meaning the compressor won't engage.

 

Good point! But as of today the static pressure is at 75 psi, so it might take a while. Perhaps I'm worrying about nothing, but cycling every ten seconds if I have to use the defroster for an extended period of time just seems like it would cause premature wear on the clutch. I probably should just have the system evacuated.

 

The "odd" thing about the A/C system is that leaks are not covered by the Platinum Warranty unless the dealer can identify that a part has failed. So, they want to charge you for a system charge unless they can see some gross problem like a cracked hose. Service writer stated that refrigerant is an evaporative (very big work for him) material and subject to loss over time. I explained to him that the A/C system is sealed and the only way that the refrigerant could "evaporate" was due to failure of a component. Needless to say, I got in my truck and left while he was still babbling.