Put some Teflon tape on the threads of the Schrader valve leaving the first couple threads bare. Some pressure switches have an o ring all the way inside where that flat piece pushes the valve. Haven't looked at a fox pressure switch in a long time.
My switch is definitely not floppy. It's pretty tight actually. If your switch is moving around, it's going to leak as the seal makes and breaks depending on movement.
Have you tried another switch?
Also, try some of this stuff. It's an A/C sealant. Put it on the O-ring and contact surface of the flare. Will help seal.
Amazon product ASIN B008HOSQQQ
Have you tried another switch?
Also, try some of this stuff. It's an A/C sealant. Put it on the O-ring and contact surface of the flare. Will help seal.
Amazon product ASIN B008HOSQQQ
Not all of them, but the vast majority of modern short style cores are these.
Riseuvo 100Pcs Schrader Tire Valve Core - American/US Valve Stems Core for Most Automotive, RV, ATV & Air Conditioning, Tire Remover Replacement https://a.co/d/2jJCxQM
This is what was in my ac system. If you ask for an ac valve core, that’s typically what you get.
Riseuvo 100Pcs Schrader Tire Valve Core - American/US Valve Stems Core for Most Automotive, RV, ATV & Air Conditioning, Tire Remover Replacement https://a.co/d/2jJCxQM
This is what was in my ac system. If you ask for an ac valve core, that’s typically what you get.
The one in your pic is a looks like a standard 1/4" flare fitting, they will all use the same Schrader core. You might try an encapsulated pressure switch for a standard HVAC application. Several vendors make them with various cut-in & cut-out ratings. The bodies are brass or steel, & usually use a copper sealing ring. Alot better than that B.S. plastic & o-ring. Supco part #'s SLP-2045 & SLP-1535 are an example.
This is it, but I was only able to use it on the low side port. Not the high side. I did not try the port on the accumulator.
Price went up. A lot. Think I paid $45
Appion MGAVCT 1/4" MegaFlow Vacuum-Rated Valve Core Removal Tool https://a.co/d/fqsQ2pB
Confirm that the accumulator port fitting is the same size as the low pressure fitting. If it is, this will work.
I can also send you mine to use if you’ll cover shipping.
But this will allow you to swap cores on a fully pressurized system.
Price went up. A lot. Think I paid $45
Appion MGAVCT 1/4" MegaFlow Vacuum-Rated Valve Core Removal Tool https://a.co/d/fqsQ2pB
Confirm that the accumulator port fitting is the same size as the low pressure fitting. If it is, this will work.
I can also send you mine to use if you’ll cover shipping.
But this will allow you to swap cores on a fully pressurized system.
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It depends.
The switch is designed to open at ~25psi and close once pressure creeps up to 45psi. WHen this occurs all depends on ambient conditions.
Assuming a properly charged system, on a 95 degree humid day, the system will likely stay engaged indefinitely. System pressures will run higher and the low side will likely never drop to a pressure low enough to open the low pressure switch.
On a cooler day, the system pressures will likely be much lower, and it's possible to occasionally hit that 25psi limit. This might be true if running the defrost on a humid 45 degree rainy day for example.
There are other factors as well. Airflow through the condensor will play a role in pressures.
When folks convert to R134a, you should really adjust the switch down to around 20-21psi. The R134a has a wider pressure differential across the orifice so it's much more likely that the lower side will approach pressures in the 20 psi range. Since a lot of folks don't adjust the switches (or just don't have the meants) it's possible to hit the low pressure cutoff a lot sooner than necessary. So you get a cycling system. It's going to be a lot more common on these r134a retrofits, especially if done on a leaking system without an adjusted pressure switch.
My new R12 system behaves as i describe above. Hot day, it runs pretty much constant and gives me 35-40 degree vent temps. On a cool day, it cycles
The switch is designed to open at ~25psi and close once pressure creeps up to 45psi. WHen this occurs all depends on ambient conditions.
Assuming a properly charged system, on a 95 degree humid day, the system will likely stay engaged indefinitely. System pressures will run higher and the low side will likely never drop to a pressure low enough to open the low pressure switch.
On a cooler day, the system pressures will likely be much lower, and it's possible to occasionally hit that 25psi limit. This might be true if running the defrost on a humid 45 degree rainy day for example.
There are other factors as well. Airflow through the condensor will play a role in pressures.
When folks convert to R134a, you should really adjust the switch down to around 20-21psi. The R134a has a wider pressure differential across the orifice so it's much more likely that the lower side will approach pressures in the 20 psi range. Since a lot of folks don't adjust the switches (or just don't have the meants) it's possible to hit the low pressure cutoff a lot sooner than necessary. So you get a cycling system. It's going to be a lot more common on these r134a retrofits, especially if done on a leaking system without an adjusted pressure switch.
My new R12 system behaves as i describe above. Hot day, it runs pretty much constant and gives me 35-40 degree vent temps. On a cool day, it cycles