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A/C receiver -dryer popped on 134a convert system. Need special?

YY1

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Gasket (I think) vented all the gas.

Thinking about getting a new unit.

Any thing I need to be aware of?

This is a factory RV2 R12 system that was converted to R134a some time ago.

Is there anything different between a 134a receiver/dryer and a stock part?

TIA
 
I've got a factory replacement 134 dryer from RockAuto that has worked fine for me. I've even had it up to 400 psi with no problems.
So no I don't think there's any difference.
 
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No I also used one from RA no problem.
 
Thanks.

Maybe I'm still unclear...

So, are they different, in a different 134a section, or with the OEM parts in the drop down for the year of car?
 
Thanks.

Maybe I'm still unclear...

So, are they different, in a different 134a section, or with the OEM parts in the drop down for the year of car?

I would say no. If I were you, I would replace the expansion valve and the drier and have it re-charged with 134 by an AC shop. Not sure why your drier blew up but they can raise to a very high pressure at idle. May have been the weak link or had too much freon. My 68 charger uses all of the factory style R12 parts except the compressor. Charged with 134 and has worked fine for the past 3 years.
 
The dryers are the same.. But once a dryer has been used with one refrigerant it can not be used with a different refrigerant... The different oils are not comparable with each other... Because of that when converting all components that are to be reused need to be throughly flushed...

R134 pressures to tend to be higher than R12... But shouldn't be a problem if the system is operating properly.... However if the air flow to the condenser is insufficient the pressure can get upwards of 4-500 PSI & at that point relief valves lift or sometimes parts fail....
 
I know some systems have an orifice valve that is the wrong size for 134 vs 12.

IIRC systems of a different design (our OEM?) have a different component that is not compatible between the two refrigerants.

Just trying to sort that all out. Figured the knowledge base here would know definitively.
 
Expansion valve, new ones are calibrated for R134..
 
The other aspect when converting from R12 to R134A and using the Chrysler RV2 compressor is the EPR (Evaporator Pressure Regulating) valve, located in the suction inlet of the compressor MUST be removed. As R134A refrigerant has different operating characteristics and pressures this valve is not necesssry. R12 refrigerant required this valve, to maintain the evaporator at a constant or nearly constant pressure, slightly above 36-38 psi to prevent icing. The thermostatic expansion valve, located in the liquid feed line to the evaporator, was cross connected to the suction line, providing a relatively constant pressure/temperature of the evaporator, maximizing cooling efficiencies and air temperature off the evaporator coil.
BOB RENTON
 
RV-2 is a poor choice for R134... The front seal is a common leak with R-12... The R134 Molecule is about half the size of an R-134 molecule so whats a slow leak on an R-12 system will drain an R-134 system in a couple weeks....
 
Except for the dryer, my seals appear to be in relatively good shape.

I needed to add about 1/2 pound every 2 years.

I can handle that.

It did have somewhat of an issue with lots of condensation on the outside of the evaporator case, which would eventually drip onto the carpet.

It never froze up and stopped cooling though.

I will definitely check for the EPR valve while it's discharged though. Thanks for that.
 
RV-2 is a poor choice for R134... The front seal is a common leak with R-12... The R134 Molecule is about half the size of an R-134 molecule so whats a slow leak on an R-12 system will drain an R-134 system in a couple weeks....

I'm aware....yes...the molecular size difference is significant between R12 and R134A. However, with a change to the shaft mechanical seal design of the RV2, which origionality was simple carbon vs ceramic single unbalanced design to that of a balanced design (relating to the operating pressures on the seal faces and not the rotational forces) would fix the leakage issues, but the axial flow and greater displacement of the newer compressors provide a higher efficiency yielding better cooling.
BOB RENTON
 
I think I'll be staying with the RV2. I like the period correct look on this car.

The cooling was pretty good, too.

Any ideas about the condensation issue?
 
Except for the dryer, my seals appear to be in relatively good shape.

I needed to add about 1/2 pound every 2 years.

I can handle that.

It did have somewhat of an issue with lots of condensation on the outside of the evaporator case, which would eventually drip onto the carpet.

It never froze up and stopped cooling though.

I will definitely check for the EPR valve while it's discharged though. Thanks for that.
Is your drain draining in the firewall.
 
No. It did have a folded portion of gasket material at the bottom of the case which was causing it to leak.

Also, the gasket shape partially blocks the drain hole area.

Both those issues are fixed. The first was a royal PITA.


What's happening now is condensation that eventually builds large enough droplets to drip off when I turn.
 
No. It did have a folded portion of gasket material at the bottom of the case which was causing it to leak.

Also, the gasket shape partially blocks the drain hole area.

Both those issues are fixed. The first was a royal PITA.


What's happening now is condensation that eventually builds large enough droplets to drip off when I turn.
Even in Florida that should not happen if the box is draining well. This is happening with all the windows closed and air on Max?
What temp do you have out of the vent?
What are your pressures?
 
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