Temporary AC Charging Solutions - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

biasword · 06-13-2022, 01:51 PM

Hi all, for transparency, im shit with hvac. I have a s14 with all ac components that isnt cooling. Can I just use one of those auto part store recharge systems to fill the system to see if the compressor will build pressure and turn on?

If it does then ill take it to a shop to vacuum and recharge it, but figured id start there.

yeah, i know its a dummy question, but a learning opportunity nonetheless

AKADriver · 06-13-2022, 02:46 PM

Was the system working and then just one day stopped? Or was it taken apart? If it was taken apart at any point do not pass go, don't try to do anything without replacing the dryer and evacuating the system.

If it just stopped working a while ago you may just have low charge. However, the gauge on those A/C kits is only designed to read correctly when the compressor is running. The green zone on the gauge corresponds to ~30psi which is what the low side pressure should be with the system on. With the compressor off, on a full charge the low and high sides will equalize to about 50-60psi typically which would show as overcharged (red zone) on the gauge.

So with the compressor not running, my take on the gauge reading would be if it's at or below the green, it's definitely undercharged, and you might try a few blips of the trigger to see if it goes up and the compressor kicks on. Anything above the green I wouldn't try adding more or you could damage the system very quickly.

silviaks2nr · 06-15-2022, 06:57 AM

You need to vacuum the sytem and check for leaks before recharging. But even before you do that you should check and see if there is pressure in the system. If there is, your problem lies elsewhere, like the pressure switch, compressor, or clutch. You can hard start the compressor by giving battery power to the 12v clutch signal if there is pressure in the system. That will let you know if it's the compressor or the pressure switch/wiring.

06-13-2022, 01:51 PM	#1
biasword Join Date: Mar 2018 Location: FL Age: 36 Posts: 45 Trader Rating: (0) Feedback Score: 0 reviews	Temporary AC Charging Solutions Hi all, for transparency, im shit with hvac. I have a s14 with all ac components that isnt cooling. Can I just use one of those auto part store recharge systems to fill the system to see if the compressor will build pressure and turn on? If it does then ill take it to a shop to vacuum and recharge it, but figured id start there. yeah, i know its a dummy question, but a learning opportunity nonetheless

06-13-2022, 02:46 PM	#2
AKADriver Post Whore! Join Date: May 2002 Location: Springfield, VA Age: 43 Posts: 3,517 Trader Rating: (1) Feedback Score: 1 reviews	Was the system working and then just one day stopped? Or was it taken apart? If it was taken apart at any point do not pass go, don't try to do anything without replacing the dryer and evacuating the system. If it just stopped working a while ago you may just have low charge. However, the gauge on those A/C kits is only designed to read correctly when the compressor is running. The green zone on the gauge corresponds to ~30psi which is what the low side pressure should be with the system on. With the compressor off, on a full charge the low and high sides will equalize to about 50-60psi typically which would show as overcharged (red zone) on the gauge. So with the compressor not running, my take on the gauge reading would be if it's at or below the green, it's definitely undercharged, and you might try a few blips of the trigger to see if it goes up and the compressor kicks on. Anything above the green I wouldn't try adding more or you could damage the system very quickly.

06-15-2022, 06:57 AM	#3
silviaks2nr Users Awaiting Email Confirmation Join Date: Nov 2004 Location: SC Posts: 2,193 Trader Rating: (10) Feedback Score: 10 reviews	You need to vacuum the sytem and check for leaks before recharging. But even before you do that you should check and see if there is pressure in the system. If there is, your problem lies elsewhere, like the pressure switch, compressor, or clutch. You can hard start the compressor by giving battery power to the 12v clutch signal if there is pressure in the system. That will let you know if it's the compressor or the pressure switch/wiring.