A/C expansion valve? 1992 Vette
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A/C expansion valve? 1992 Vette
I know the receiver/dryer requires periodic maintenance, but does my 1992 Corvette have an A/C expansion valve, too?
If so where is it located? Should the expansion valve be changed if you convert from R12 to R134a?
If so where is it located? Should the expansion valve be changed if you convert from R12 to R134a?
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Screened orifice or expansion valve is located at the Evaporator Inlet. As the compressor wears, it sheds metal which is trapped in the screen. This reduces the metered amount of liquid refrigerant that gets into the Evaporator and raises operating pressures. To see if it's a problem, you need to hook up a manifold gage set. If rebuilding or converting, best to remove and clean it or just buy a new one - they're about $9. There are variable orifices for R134 conversions. Opinions seem to be all over the place about their benefit. Do swap out the Accumulator any time the system is exposed to the atmosphere.
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Originally Posted by SunCr
Screened orifice or expansion valve is located at the Evaporator Inlet. As the compressor wears, it sheds metal which is trapped in the screen. This reduces the metered amount of liquid refrigerant that gets into the Evaporator and raises operating pressures. To see if it's a problem, you need to hook up a manifold gage set. If rebuilding or converting, best to remove and clean it or just buy a new one - they're about $9. There are variable orifices for R134 conversions. Opinions seem to be all over the place about their benefit. Do swap out the Accumulator any time the system is exposed to the atmosphere.
I can get the valve locally for $5 at AutoZone or NAPA and the dryer for about $55. I can also get the replacement R134a for about $22 a can.
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Found out over the weekend my R134a got contaminated with trace amounts of R12. Apparently, the conversion was not done properly.
I'm taking my Vette Monday to an HVAC/radiator specialty shop and have them put it on a machine called a "Scavenger" by Robinair.
It's a dedicated, recovery-only machine built for this purpose. This process involves pulling a vacuum on the system, and allowing the machine to purge the air automatically.
This process, however, can take upwards of an hour to complete and may not be able to remove all air. Still, it's my best option to date. We'll keep you posted....
I'm taking my Vette Monday to an HVAC/radiator specialty shop and have them put it on a machine called a "Scavenger" by Robinair.
It's a dedicated, recovery-only machine built for this purpose. This process involves pulling a vacuum on the system, and allowing the machine to purge the air automatically.
This process, however, can take upwards of an hour to complete and may not be able to remove all air. Still, it's my best option to date. We'll keep you posted....
Last edited by onedef92; Jun 27, 2005 at 02:00 PM.
