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View Full Version : What is the pressure for 134a in a refrigerator maytag?


lukatush
Jul 9, 2011, 04:40 PM
Hello all:

I am having problem charging my Maytag refrigerator.
After I found two leaks on the high side I brazed them and pulled a deep vacuum although gage was showing 30 inch Hg. I left it like that for some time to see if the gage would move, but did not. At this time I proceeded to charge the unit. The problem I am running into is that the suction line is freezing up and only when I go over 30 psig the frost goes way.

Question is, what is the proper charge "psig" for 134 A on the refrigeration system?

Name plate shows 5 oz.

Thanks.

drtom4444
Jul 10, 2011, 10:17 AM
You need to weight the charge in. It should hold 5 oz. of freon and no more. It sounds like you have a major overcharge. A slight overcharge will frost the suction line coming out of cabinet. Release all gas and vacuum again. Then weight can of gas. Turn can upside down to get liquid only. If you have already charged from can getting gas out discard can and get new one as the R-134 freon is a mix of gases and you will have removed more of one gas than another and refrigerator will never work right. Pull good vacuum on unit. Hook up new can, turn upside down. Have gauge valve closed. Slightly crack valve on can to purge line of air. Close valve on can.Open valve on gauges to can to put vacuum on hose to can (the unit should still be under vacuum), but keep can valve closed. Then close valve on gauge and open valve on can to fill hose with liquid freon. A six foot hose will hold about 3-4 oz. of liquid freon. Keep can charging liquid at all times. When hose is full close valve on can and open to unit. Repeat once, close valve on gauge and can and you should read about -20°F when you turn unit on. Your gauge temp reading will be 20° less than the temp on outside of coils which should go down to at least 0° F or less. The actual pressure you should begin to see on gauge should be around 0 PSI and there may be a tiny bit of frost on line coming out of cabinet. Compressor should run cool and not be too hot as the gas cools compressor, but too much is not good. If you release gas from unit to get charge right it will unbalance gases. Do not have high side line hooked up while charging such a small unit as line will hold too much Freon and mess up readings. Hope this helps. DrTom4444

lukatush
Jul 23, 2011, 03:05 PM
Thank you drtom.