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Old 04-21-2008, 07:06 AM   #1
streetstar
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Denied ! (ac still not cold)

Wel, i put some r-134 service fittings on my compressor and voila! Low side pressure is at 60 and its still not getting cold

Anything else that can go wrong with these things?

I have a giant York compressor that does not appear to have a clutch on the front, so i dont know if its engaging or not, or if its always engaged ---

for now its lookin like 2 wasted cans of refrigerant

pic of compressor ---

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Old 04-21-2008, 07:35 AM   #2
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Re: Denied ! (ac still not cold)

All r134 systems that I seen have about 25-30psi on the low side. Almost sounds like there is a restriction somewhere.
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Old 04-21-2008, 01:23 PM   #3
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Re: Denied ! (ac still not cold)

28 # is the freezing point for R-134A . In the picture there is no belt . Also looks like there could be a wiring problem . It appears the clutch wire has a wire nut on it . Might make sure you have power to the clutch . For safety reasons always make sure you monitor the high pressure side of the system as well when charging .
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Old 04-21-2008, 05:00 PM   #4
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Re: Denied ! (ac still not cold)

Quote:
Originally Posted by hotrod 80 View Post
28 # is the freezing point for R-134A . In the picture there is no belt . Also looks like there could be a wiring problem . It appears the clutch wire has a wire nut on it . .
its an old pic -- it has a belt now -- i just posted the pic to show the type of compressor

did not know about the 28# freezing point -- the 12-134 conversion instructions stated to pressure it to 50-55# at 80 degrees outside air.
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Old 04-21-2008, 05:05 PM   #5
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Re: Denied ! (ac still not cold)

you have been giving proper info. check you pressure switches, checked fuses and relays. get the low side between 30 and 40 psi and the top side should take care of itself. remember dont use as much 134 as you would 12
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Old 04-21-2008, 06:05 PM   #6
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Re: Denied ! (ac still not cold)

The 28 # s is directly from the pressure to temperture chrt for 134 A . anything below that and the evaporator will try to freeze . to much suction pressure will result in high suction super heat or liquid flood back . Your compressor cannot pump liquid .

Also on top of the liquid line filter/drier ( passenger side fender well ) is a sight glass . You may have to clean it with a rag and maybe add a drop of oil to the glass , but you should see refrigerant moving through this glass . If you have a fixed restricter you may see some vapor in it when fully charged . Go by your pressures . If discharge gets above 275 and you still have low suction you more than likely have a problem . If it is an expansion valve system that has been open for some time it may have a stuck valve due to moisture .If i am not mistaken the front of that compressor will be spinning when the clutch is engaged .
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Last edited by hotrod 80; 04-21-2008 at 06:14 PM.
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Old 04-21-2008, 10:11 PM   #7
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Re: Denied ! (ac still not cold)

The dryier is on the fender well can you see liquid running through it or is it just sitting there. I wouldn't trust those two radiator clamps on the black hoses either. Quick way to check compressor is run a jumper to the compressor straight to the battery see if it comes on. Then you know there is a problem in your wiring some place.
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Old 04-22-2008, 02:22 AM   #8
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Re: Denied ! (ac still not cold)

On a York, if the middle of the pulley is turning the clutch is engaged, if it's stationary it's not. I run a 209 for my suspension.
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