A/C will not take any more refrigerant - cannot fill to spec
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Joined: Dec 2009
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2005 CL65 (current), 2001 CL600 (chopped)
A/C will not take any more refrigerant - cannot fill to spec
01 CL600. Car bought in winter. AC never worked. Just getting around to fixing it now because it wasn't necessary before.
Vacuumed out all old refrigerant, tried to put in some new R134. It took a can and a half, but not enough to spec. I put it in the low side. Now it's stuck at 6-7 bar of pressure, and if I try to put any more in it just won't take it. When I touch the hoses I don't feel any flow through the low or high. I can see the (torque limiter) shaft turning on the compressor. No, the "EC" button is not on, though after a while it will be forced on and will throw the code "refrigerant low". Low side has same pressure as high side. Both hi and low indicate about 75 psi. I hear some rattling in the area, not sure if it's from the a/c compressor or power steering pump (ABC tandem pump). I manually engaged the compressor through diagnostic computer and it still won't suck any more freon into the low side.
Is my compressor bad?
Vacuumed out all old refrigerant, tried to put in some new R134. It took a can and a half, but not enough to spec. I put it in the low side. Now it's stuck at 6-7 bar of pressure, and if I try to put any more in it just won't take it. When I touch the hoses I don't feel any flow through the low or high. I can see the (torque limiter) shaft turning on the compressor. No, the "EC" button is not on, though after a while it will be forced on and will throw the code "refrigerant low". Low side has same pressure as high side. Both hi and low indicate about 75 psi. I hear some rattling in the area, not sure if it's from the a/c compressor or power steering pump (ABC tandem pump). I manually engaged the compressor through diagnostic computer and it still won't suck any more freon into the low side.
Is my compressor bad?
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Joined: Nov 2001
Posts: 4,260
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From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
01 CL600. Car bought in winter. AC never worked. Just getting around to fixing it now because it wasn't necessary before.
Vacuumed out all old refrigerant, tried to put in some new R134. It took a can and a half, but not enough to spec. I put it in the low side. Now it's stuck at 6-7 bar of pressure, and if I try to put any more in it just won't take it. When I touch the hoses I don't feel any flow through the low or high. I can see the (torque limiter) shaft turning on the compressor. No, the "EC" button is not on, though after a while it will be forced on and will throw the code "refrigerant low". Low side has same pressure as high side. Both hi and low indicate about 75 psi. I hear some rattling in the area, not sure if it's from the a/c compressor or power steering pump (ABC tandem pump). I manually engaged the compressor through diagnostic computer and it still won't suck any more freon into the low side.
Is my compressor bad?
Vacuumed out all old refrigerant, tried to put in some new R134. It took a can and a half, but not enough to spec. I put it in the low side. Now it's stuck at 6-7 bar of pressure, and if I try to put any more in it just won't take it. When I touch the hoses I don't feel any flow through the low or high. I can see the (torque limiter) shaft turning on the compressor. No, the "EC" button is not on, though after a while it will be forced on and will throw the code "refrigerant low". Low side has same pressure as high side. Both hi and low indicate about 75 psi. I hear some rattling in the area, not sure if it's from the a/c compressor or power steering pump (ABC tandem pump). I manually engaged the compressor through diagnostic computer and it still won't suck any more freon into the low side.
Is my compressor bad?
Thread Starter
Member
Joined: Dec 2009
Posts: 141
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2005 CL65 (current), 2001 CL600 (chopped)
If I vacuum out again, replace drier, and that doesn't solve the problem, can the same drier be used again after I replace compressor? Or should I go straight to replacing the compressor? Thanks for your response.
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Joined: Nov 2001
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From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
My suggestion to you is to take it to a GOOD airconditioning shop that works on MB's and have it at least diagnosed. Then make a decision as to how you want to proceed. Just throwing parts and your time at it without knowing whats actually wrong is not the way to go about this. The money to do this will be well spent
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2005 CL65 (current), 2001 CL600 (chopped)
Pressure gauges I have. Temp I can read through diagnostic computer from sensors already in place in the system. Drier is bolted on - can be easily replaced. By evap/dryer I assume you mean the accumulator that attaches to the condenser.
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From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
You seem to be having difficulty finding out exactly whats wrong. You have a set of the dual gages and valves used to work on refridgeration?? You have the temp conversion chart ?(not just the temp thermometor) You have the leak check equipment? The evap/dryer may be bolted to the car but I believe its soldered in to the refridgerant line. There is no accumulator that I am aware of. My final suggestion is what I said before have it professionally diagnosed and then make a decision. By the way, Compressors are quite expensive. Not trying to be funny or sarcastic but seems that you have enough knowledge to be a bit dangerous and thats not going to resolve your issue.
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98 Brilliant Silver E320 Wagon
Just a minor point. Accumulators are used with Orfice tube pressure regulators and Receiver/Dryers are used with Thermal Expansion Valves. Their function is pretty much the same -- keep liquid refrigerant from reaching the compressor. People tend to use the two terms interchangeably.
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MBWorld Fanatic!
Joined: Nov 2001
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From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
Just a minor point. Accumulators are used with Orfice tube pressure regulators and Receiver/Dryers are used with Thermal Expansion Valves. Their function is pretty much the same -- keep liquid refrigerant from reaching the compressor. People tend to use the two terms interchangeably.
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From: SoCal
98 Brilliant Silver E320 Wagon
I agree with the advice to see a A/C tech for almost everyone with A/C issues. It's not really a very good candidate for DIY. Just having a set of gauges isn't much good unless you understand the principles. And considering the high side pressure you'll be in for a surprise if you guess wrong.
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From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
Yes, definitely change the drier if the system has been running without a charge or a conversion from R12 to R134. As far as I know the accumulator does not have a drying/cleaning function just accumulates the liquid refrigerant.
I agree with the advice to see a A/C tech for almost everyone with A/C issues. It's not really a very good candidate for DIY. Just having a set of gauges isn't much good unless you understand the principles. And considering the high side pressure you'll be in for a surprise if you guess wrong.
I agree with the advice to see a A/C tech for almost everyone with A/C issues. It's not really a very good candidate for DIY. Just having a set of gauges isn't much good unless you understand the principles. And considering the high side pressure you'll be in for a surprise if you guess wrong.
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From: Louisiana
03 E500 and Corvette
If the expansion valve has failed closed you will be able to pull a vacuum but not able to fully fill the system. I normally use the first can with vacuum as a wet fill. The rest are gas fill.
I suspect the expansion valve is defective. This can be seen with gauges indicating very high, high side pressures and close to normal low side.
I suspect the expansion valve is defective. This can be seen with gauges indicating very high, high side pressures and close to normal low side.
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1985 300cd 1994 E320 cab.
if your gauges read the same pressures and your compressor is on the reed valves are bad and you need a compressor also go ahead and put in a expansion valve in and inspect it for debris when you pull it out and a drier if you find debris flush the suction line and the evaporator so it does not happen again
Last edited by mbwhat; May 8, 2010 at 12:13 PM.
