| Re: Strange Issues with Air Conditioning |
Subject: Re: Strange Issues with Air Conditioning by Churchkey on 2012/9/27 9:11:30 You can check the amount of charge in a system by checking the low side pressure. Have the vehicle in shade & insure the interior is at ambient temp. A floor fan or box fan blowing at the condenser is recommended. Windows up, start engine, AC set to lowest temp setting, recirculate, max blower fan speed, exit vehicle, close doors. Use some type of device to hold the throttle open @ 1500 rpm. Allow the system to operate approximately 5 minutes to normalize before reading pressure. The low side quick read: up to 80* ambient temp 28# up to 90* 28-32#, over 90* 32-36#. Pressure below above #'s = add more freon. Pressure above stated #'s = let some freon out via recovery equipment. Its not an exact science as some would lead you to believe, a difference of say 2# will show minimal if any difference in vent discharge temps. Center vent discharge temp = 36 to 48* Discharge temps vary dependent on temp blend door, recirculate door operation, cleanliness of the evaporator, fan speed of the blower motor, loose vent ducts etc. Rinsing the condenser aids freon cooling. A garden hose works, commercial condenser solvents are available. The compressor will run without freon in the system for charging purposes. To enable the compressor: Remove the E connector plug from the low pressure switch. Use a jumper wire or paper clip to connect the terminals inside the E connector. Leak testing with an electronic tester = best results. Mine will pick up a leak as small as 1/4 ounce yearly. Good luck |
