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EDCivic
30-11-2014, 02:47 PM
A few years back the low pressure sensor went west in our ED Civic and so in having it repaired, the R12 (now banned) was replaced with R134a which has resulted in a cabin cooling system which feels like the same as placing an ice block in each vent and turning the fan on high. It has also caused the vanes in the compressor to rattle at idle. Is there a better gas to use that has the same cooling efficiency as R12 (with the exception of LPG) ? Could one retro fit a R134a setup into the ED from a slightly later model e.g. EG ? When we had R12 I must admit it was dam good though the car lost about 50% of its power !

AusVTi-R
30-11-2014, 03:22 PM
Correct me if i'm wrong, but I don't believe it's as easy as just replacing the gas from R12>R134a. I thought an entire retro-fit kit had to be installed to begin with?
Once again if i'm wrong with the retro-fit kit, maybe inspect for leaks in the system (your local mechanics should be able to this with the right gas recovery system and not charge you for a full drain and replenishment of the gas).

EDCivic
30-11-2014, 04:13 PM
You are totally correct, but the problem is that R12 is now illegal to use so that is why took the cheap option put R134a in. The poor old ED had a A/C system specifically designed for R12 which from what I have read has different properties to that of R134a and hence how it performs poorly if you replace one gas with another. I have read about other refrigerants (http://hychill.com.au/products/minus-30) that have similar characteristics as R12 but I would like to hear from others with ex R12 setups and what they did to overcome the poor performance with R134a. I found this article regarding R12 over R134a in a R12 setup....." There is no question that R12 performs better than R134a, but by how much? According to statistics, for an R134a system to have comparable performance to R12, the condenser must be increased by 30%. That is a huge feat. I am not whether that correlates which stating that it performs 30% worse when in the same systems, but one can make a pretty good judgement that if it requires 30% greater surface area to meet prior performance, it is safe to say R12 or CFC-12 is far superior. "

dove grey 64
30-11-2014, 04:39 PM
Dont know but ive got r134a in my ee wagon which has the same setup as a ed and its cold as, hurts your chest cold.

EDCivic
30-11-2014, 04:46 PM
Wish ours went as well ! Our ED has also an additional issue since the R134a was used in that the vanes in the compressor rattle like cardboard against the spokes of a bicycle wheel at idle. It never did that before and only goes away anything above 1,000 rpm.

AusVTi-R
30-11-2014, 05:54 PM
You are totally correct, but the problem is that R12 is now illegal to use so that is why took the cheap option put R134a in. The poor old ED had a A/C system specifically designed for R12 which from what I have read has different properties to that of R134a and hence how it performs poorly if you replace one gas with another. I have read about other refrigerants (http://hychill.com.au/products/minus-30) that have similar characteristics as R12 but I would like to hear from others with ex R12 setups and what they did to overcome the poor performance with R134a. I found this article regarding R12 over R134a in a R12 setup....." There is no question that R12 performs better than R134a, but by how much? According to statistics, for an R134a system to have comparable performance to R12, the condenser must be increased by 30%. That is a huge feat. I am not whether that correlates which stating that it performs 30% worse when in the same systems, but one can make a pretty good judgement that if it requires 30% greater surface area to meet prior performance, it is safe to say R12 or CFC-12 is far superior. "

Ahhh now I understand your dilemma a bit better. Can't say I've heard of this Minus 30 refrigerant before but would seem to save you the hassle of swapping to a full R134a system. However the fact it basically says it take 30% more compressor efficiency to run R134a over R12 added to the fact that 'dove grey 64's' same setup is running well would indicate your compressor could be on the way out...regardless if you change to this Minus 30 stuff.

EDCivic
30-11-2014, 06:15 PM
Maybe the compressor is on its way out as the old girl has now 400,000k's on the clock, though after buying it some 14 years ago with 90,000k's, the compressor was running perfectly just days before the low pressure sensor died. Have sent a message to HiChill for advice/local contacts.

Thanks all for following up.

grifty
30-11-2014, 09:47 PM
If you really want the A/C system to be cold as on R134A i'd use a EK compressor and install a parallel flow condensor. You'll need the original compressor lines modified with EK fittings.

Or get a refurbished compressor, install a new receiver/dryer, o-rings and get the whole system vacuumed + gassed.

Or look into hychill.

dove grey 64
02-12-2014, 10:48 AM
Wonder if they topped up your compressor with ac oil stuff, maybe they didn't and that's why its rattling

grifty
02-12-2014, 12:41 PM
Rattling is quiet common with R12 converted to R134a, I think it's due to old compressor age.

My brand new compressor from Honda never rattled when I ran R134A.

cbauto
02-12-2014, 12:43 PM
I have 134a compressor FS if interested.

EDCivic
02-12-2014, 08:53 PM
Wonder if they topped up your compressor with ac oil stuff, maybe they didn't and that's why its rattling
Unfortunately there is enough oil in there for a decent sized fish and chip shop. Maybe after 400,000 ks it has finally died but..........

EDCivic
02-12-2014, 08:55 PM
I have 134a compressor FS if interested.
OK....I could be interested pending further diagnostics and price ???

cbauto
02-12-2014, 09:12 PM
OK....I could be interested pending further diagnostics and price ???
off a 97 obd2a dc4
$40 plus ship

pretty sure all compressor mounting is the same. only difference is the brackets. powering it up is only positive signal.