R12 -> R134a 1989 Porsche Kit Questions

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HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Fri Jul 21, 2017 4:54 pm

I think the process would be:
- starting with pump running and manifold wheels open
- close manifold wheels
- turn off pump
- attach can and secure service hose at both ends
- puncture can
- bleed service hose at manifold to the outside
- close service hose at manifold
- slowly open manifold wheels, first high side then low side
- let the R134a flow until it stops (how do I know when it stops, sound or watch pressure?)
- the instructions (see my first post) say to stop at 10 psig on the initial fill (will do this twice)
maybe just let the pressure go above 10psig to empty the can, the total fill will be 36 oz. (see inst. above)
- after filling is stopped then back out the quick disconnect wheels
- close off the can (can this be done with the valve I get at the auto parts store?)
- now what to do with the punctured can if there is anything left and I can't seal it

Thanks and sorry to review the obvious to all of you that do this often
HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Fri Jul 21, 2017 4:55 pm

forgot to add:
- disconnect QD fittings
- install plastic caps
HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Fri Jul 21, 2017 6:42 pm

It does not appear to be super easy to buy a small can of pure R134a at a local auto parts store in CA.
It seems there is a deposit and return process involving a valve that I guess is permanently attached to the can.
I have to return the empty can? Anyone know how this goes here in CA?
Please advise which place(s) to try first: Autozone, OReilly, PepBoys, etc. etc.
Thanks.
HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Fri Jul 21, 2017 11:37 pm

Looks like Wally Mart is providing the best listing for a small can of pure R134a. I'll go there tomorrow and see if I can get a can.

https://www.walmart.com/ip/R-134a-Refri ... y/16888798
HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Sun Jul 23, 2017 6:46 pm

At this point I'm going to try making and letting dry air back in.
I bought a desiccant filter and I'm thinking if I very slowly bleed air back in I'll have low moisture air back in the system waiting for the shop appointment in Aug.
HC3
Posts: 47
Joined: Thu Jul 06, 2017 6:46 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby HC3 » Thu Aug 03, 2017 7:44 am

Got the system charged on Tuesday.
The process:
1 - evac for 20 minutes and charge with R134a to 15 psig (look for leak down)
2 - recover and evac for 20 minutes and charge with R134a to 15 psig (look for leak down)
3 - recover and evac for 1.5 hours and charge with 36 oz. of R134a (at idle low press. 22 psig, high 210 psig at 85F outside temp.)

No leaks found.
Testing so far outside temp. 93F min. vent temp. 43F. This is cruising at freeway speed.
When I park in the garage there seems to be water dripping out for quite awhile.
I'm pretty happy at this point, everything appears to be working as anticipated.
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Cusser
Posts: 271
Joined: Sun Apr 24, 2016 6:29 am

Re: R12 -> R134a 1989 Porsche Kit Questions

Postby Cusser » Thu Aug 03, 2017 1:11 pm

HC3 wrote:Got the system charged on Tuesday. No leaks found.


Good


HC3 wrote:Testing so far outside temp. 93F min. vent temp. 43F.


Very good


HC3 wrote:When I park in the garage there seems to be water dripping out for quite awhile.


Yep, the moisture from the cab air is condensing on contact with the cold evaporator, and then is "leaving the building" !

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