Air conditioning not working

anbran123 · Post by **anbran123** » 19 Aug 2012, 17:44

I have "zero" A/C. I've tested the refridgerant pressure and its "full"...The compressor doesn't run for some reason...I am curious...could it be a fuse or a relay or something?!

1999 XC70 275,000 km

Post by **tjts1** » 19 Aug 2012, 17:50

When you say its full, how many PSI in the system with the AC clutch disengaged? Full with the AC clutch engaged is in the 30-40PSI range while full with the AC clutch disengaged in the 100PSI+ range as measured at the low side port. If the pressure is too low in the system to begin with, the AC clutch will never engage.

anbran123 · Post by **anbran123** » 19 Aug 2012, 18:12

I am using a recharging gauge. The pressure is represented by colors... It is at the top of the blue range...

My other V70, the needle was in the green range and the compressor was cycling on and off every 3 -5 seconds...Which is apparently indicative of low pressure. When I topped it up...the air was cold and the comp. cycled much less frequetly...

madspeed50 · Post by **madspeed50** » 19 Aug 2012, 19:15

did it just stop worjung all at once or has it been getting worse for some time?

Yep, sent from my rooted, rommed Galaxy Nexus....

Post by **tjts1** » 19 Aug 2012, 19:23

anbran123 wrote:I am using a recharging gauge. The pressure is represented by colors... It is at the top of the blue range...

My other V70, the needle was in the green range and the compressor was cycling on and off every 3 -5 seconds...Which is apparently indicative of low pressure. When I topped it up...the air was cold and the comp. cycled much less frequetly...

You need a pressure gauge with numbers on it. Most gauges like that assume the clutch is engaging which means the green range is 30-40psi. If your pressure is that low with the clutch not engaged, you probably need a recharge. Some recharge kits come with a hose and gauge. I would start with that. Turn on the engine, AC and fan on high. Connect the recharge hose to the low side and check the pressure. Take note if the AC clutch is engaged or disengaged. Then start adding gas until the AC clutch engages and pressure on the gauge drops. The numbers on gauge are only relevant with the AC clutch engaged.