Combines Air conditioner pressure

[Ilnewholland]

I'm not sure what the correct pressure should be, but maybe around 20-30IJ If you have a vaccum then it's to low. See if you have a lot of bubbles in the site glass also. With 134a you will always have some bubbles running even if it's full. You may want to open the top of the cab up and check to see if it clean up there. I had that get all stuffed up and wouldn't cool anymore one time. Ilnh

 

[Silver4life]

Your low side should be about 17. I wouldn't worry about the low, instead look at the high side. Should read about 190 on a 70 degree day. In general 134A will be 10-20 higher than R-12. Sounds more like a air flow problem then a charge like Ilnewholland says.

 

[justapurrin]

when the pump runs for a few seconds how long does it take for it to kick on again after it kicks outIJ

 

[Shane_IN]

It will run for about 5 seconds then shut off for about 15 or so. I think the system is overcharged, there is almost 30 psi in the low side. I will have to get my relative to come out and check for sure and reclaim the freon if necessary. Thanks for the help.

 

[justapurrin]

if the pump constantly is cycling in and out every 5 to 15 seconds then the system is nearly completely empty. the system should not cycle very often at all weather it is hot or cold and the gauges are very misleading it can show 30 psi on the low side and still be nearly empty!

 

[tv140]

You need to jump the compressor clutch with a 12v power supply. Then record what the ACTUAl low side pressure is at this time. Also, very important to make note of high side pressure as well. If the system is overcharged, theoretically, both pressures should be high. If the expansion valve is stuck, you may see a extremely low low side pressure, and a high high side pressure. Check it out some more and post the results.