134a Conversion Question
Thread Starter
Melting Slicks
Joined: Nov 2001
Posts: 2,214
Likes: 0
From: Casa Grande AZ
134a Conversion Question
I'm still working on my AC. Got a couple of questions.
1. When converting I understand I should adjust the POA valve. Where is the adjustment? When I look inside the POA valve on the end that goes to the evaporator, all I see is a plate with three slots around it's perimeter. On the bottom end I do see a nut and post but no slot on the post for adjusting. I understand the adjustment is a lock nut/screw setup.
2. How much oil should I put in the compressor? The instructions say to "consult manufacturers specs" or to go by what came out of the old one. There isn't an old one! I understand it should be PAG or POE oil.
Thanks!
1. When converting I understand I should adjust the POA valve. Where is the adjustment? When I look inside the POA valve on the end that goes to the evaporator, all I see is a plate with three slots around it's perimeter. On the bottom end I do see a nut and post but no slot on the post for adjusting. I understand the adjustment is a lock nut/screw setup.
2. How much oil should I put in the compressor? The instructions say to "consult manufacturers specs" or to go by what came out of the old one. There isn't an old one! I understand it should be PAG or POE oil.
Thanks!
Melting Slicks
Joined: Aug 1999
Posts: 3,123
Likes: 13
From: Hollywood, Florida
Re: 134a Conversion Question (lbell101)
Larry,
If I remember correctly, Zwede is the one who posted about the POA valve adjustment. Hopefully he will still have that info for you.
Best of luck!
If I remember correctly, Zwede is the one who posted about the POA valve adjustment. Hopefully he will still have that info for you.
Best of luck!
Race Director
Joined: Sep 1999
Posts: 11,358
Likes: 379
From: Plano TX
Re: 134a Conversion Question (lbell101)
On my POA valve there was a slot on the thing with the nut. I got my POA valve from NAPA and I don't know if the factory POA valve has this adjustment???
The adjustment is on the side that goes up when installed.
I adjusted mine 1/4 turn CCW.
The adjustment is on the side that goes up when installed.
I adjusted mine 1/4 turn CCW.
Thread Starter
Melting Slicks
Joined: Nov 2001
Posts: 2,214
Likes: 0
From: Casa Grande AZ
Re: 134a Conversion Question (zwede)
Thanks!
I think I'll go to Napa tomorrow and order one. There isn't an adjustment on the top side at all. Did you order an expansion valve too?
I think I'll go to Napa tomorrow and order one. There isn't an adjustment on the top side at all. Did you order an expansion valve too?
Le Mans Master
Joined: Nov 2000
Posts: 5,210
Likes: 104
From: Fort Worth TX
St. Jude Donor '06
Father & Son St. Jude Donor '09
Re: 134a Conversion Question (lbell101)
Quoting from a book I bought, ". . . for HFC-134A use, be sure to get an expansion valve calibrated for the new refridgerant."
Elsewhere in the book, the author states clearly that outlet air temperatures will not be as low or lower than R12 without a properly calibrated expansion valve. With a properly calibrated expansion valve, lower duct outlet temperatures are common with 134A.
All that said, I haven't looked into any of the specifics yet . . . I've been meaning to call and check on a new evaporator and see if the new replacements have a properly calibrated valve or if you have to have it modified somehow or replaced with another valve.
Zwede, what did you do about your expansion valve?
Elsewhere in the book, the author states clearly that outlet air temperatures will not be as low or lower than R12 without a properly calibrated expansion valve. With a properly calibrated expansion valve, lower duct outlet temperatures are common with 134A.
All that said, I haven't looked into any of the specifics yet . . . I've been meaning to call and check on a new evaporator and see if the new replacements have a properly calibrated valve or if you have to have it modified somehow or replaced with another valve.
Zwede, what did you do about your expansion valve?
Thread Starter
Melting Slicks
Joined: Nov 2001
Posts: 2,214
Likes: 0
From: Casa Grande AZ
Re: 134a Conversion Question (74-Roadster)
I have a new expansion valve coming in tomorrow. However, I am unable to find a new POA valve. ALL the parts stores say they can't get it. ALL the Vette sources don't have it either. I'm thinking of staying with the R12 for now as I know it will cool better if I can't adjust the POA.
Any idea of the amount of oil to add to a brand new compressor??
Thanks!
Any idea of the amount of oil to add to a brand new compressor??
Thanks!
Race Director
Joined: Sep 1999
Posts: 11,358
Likes: 379
From: Plano TX
Re: 134a Conversion Question (74-Roadster)
Quoting from a book I bought, ". . . for HFC-134A use, be sure to get an expansion valve calibrated for the new refridgerant."
Elsewhere in the book, the author states clearly that outlet air temperatures will not be as low or lower than R12 without a properly calibrated expansion valve. With a properly calibrated expansion valve, lower duct outlet temperatures are common with 134A.
All that said, I haven't looked into any of the specifics yet . . . I've been meaning to call and check on a new evaporator and see if the new replacements have a properly calibrated valve or if you have to have it modified somehow or replaced with another valve.
Zwede, what did you do about your expansion valve?
Elsewhere in the book, the author states clearly that outlet air temperatures will not be as low or lower than R12 without a properly calibrated expansion valve. With a properly calibrated expansion valve, lower duct outlet temperatures are common with 134A.
All that said, I haven't looked into any of the specifics yet . . . I've been meaning to call and check on a new evaporator and see if the new replacements have a properly calibrated valve or if you have to have it modified somehow or replaced with another valve.
Zwede, what did you do about your expansion valve?
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