I forgot to add that you would have high low side pressures if there was no orifice tube or somehow refrigerant was bypassing it. David Teitelbaum --- In dmcnews@xxxxxxxxxxxxxxx, "jtrealtywebspannet" <jtrealty@...> wrote: > > High low side pressures can be caused by air in the system, a blockage to the compressor, too much refrigerant, and not enough air movement over the condenser and/or evaporator coil. Not all cans have the same amount of refrigerant. Some are 12 oz, 14, and 16. When using -134 you are supposed to use 10% less than the -12 fill (rule-of-thumb). That means you should put about 2# in by weight. You fill by watching the low side AND the high side. If you do not know if the system is functioning properly you should fill by weight and only watch the gauges in case the pressures get way out of range. The motor should be running around 1,000 RPM, Mode switch on Normal, the low pressure switch jumpered, the fan speed on 4 and the cooling fans running. I fill with liquid into the low side through an orifice so I am pushing in droplets of liquid, not large slugs of liquid. Once you get the low side up to around 20 psi you can remove the low pressure jumper. Finish filling till you get the weight you need or the compressor cycling as it should. Might require adjusting the low pressure switch, especially if you are using -134. You are looking for a discharge temp from the vents of about 20 degrees lower than the ambient (outside) air. If it is 80 outside, 60 would be acceptable inside on Normal. > David Teitelbaum > > --- In dmcnews@xxxxxxxxxxxxxxx, Stephen Rice <stevedmc@> wrote: > > > > Thanks for the info everybody. It was late last night when we were > > filling it with r134a and I guess I was just being super careful. At > > first we had to jumper the compressor to get the clutch to engage but > > after getting some r134a into the system I plugged the compressor back > > into its 12v line and it stayed engaged by itself. I never did rev > > the engine, but looking back I guess I should have. It was just super > > late when we were finishing up, I was tired, and I was scared of > > adding a second can because the gauge was reading 40 pounds of > > pressure at idle. I didn't want to risk adding another can, putting > > too much pressure in the system and then popping a hose. > > > > The good news is I will be close to Drew's apartment tonight. I'll > > put an extra can of r134a in my car, bring my gauges, and offer to > > stop by tonight. I'm curious to see what pressure the gauge reads > > once we rev the engine a little bit. > > > > I don't remember having to rev the engine last time I filled my car, > > but I may have it set to idle higher than Drew's. I guess we will see > > what happens tonight. > > > > -Steve Rice > > #16510 > > > > On Wed, Jul 25, 2012 at 7:27 AM, content22207 <brobertson@> wrote: > > > You need 2 cans of freon. With one can only the compressor should be cycling like crazy when the engine revs up. > > > > > > First can is indeed sucked right in, but the second can can take forever. > > > > > > Here's a trick I use to speed things up: hold the second can in your hand. As soon as the compressor disengages (which you can force it to do by simply unplugging the clutch power lead), turn the can upside down. Low side pressure at that time will be ~30 psi -- well below can pressure. The can will empty much more quickly as a liquid than as a gas. You don't want to pour liquid freon into the compressor while it's spinning. I can empty a second can in just a minute or two this way. > > > > > > Normal A/C pulls outside air over the evaporator rather than inside air. It's only useful if temps inside the car are higher than outside temps (after sitting in the sun for example). Otherwise you want to use Max A/C, which recirculates inside air just like your household A/C. > > > > > > Also avoid the temptation to use Fan Speed 4 -- the more time air spends in contact with the evaporator, the more heat transfer can take place. > > > > > > Bill Robertson > > > #5939 > > > > > > > > > --- In dmcnews@xxxxxxxxxxxxxxx, stevedmc@ wrote: > > >> > > >> Tonight I spent a few hours helping someone flush his AC, put ester oil in the compressor, vacuum it, and then fill it with r134a. > > >> > > >> To my surprise we were only able to get a little more than one can of 134a in his system before the gauge started reading 40lbs of pressure. > > >> > > >> He took a drive down the highway and got vent temps of 60 degrees on the normal setting. Unfortunately the max setting is not working in this car and I only know the max setting gives me a vent temp of 44 degrees. He has my thermometer so I won't be able to check my vent temp on normal tomorrow. > > >> > > >> Can anyone share what vent temp they get with r134a in the normal setting? I just want to know if a 60 degree vent temperature is common on the normal setting. > > >> > > >> Thanks > > >> > > >> > > >> -- > > >> Steve Rice > > >> #16510 > > >> > > > > > > > > > > > > > > > ------------------------------------ > > > > > > To address comments privately to the moderating team, please address: > > > moderators@ > > > > > > For more info on the list, tech articles, cars for sale see www.dmcnews.com > > > > > > To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! 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