Jump to content
HybridZ

Best Ac options?


jvanen

Recommended Posts

Sorry if this is a repost. I couldn't find the info searching. Wanting to convert my Ac over to 134. I have a 77280z. I've heard some say to replace the pump and drier, and I've heard others say to just use and air compressor to blow out the old oil and freon and go back in with new oil and 134. I just want some nice cold AC So tell me whats up and what my best options are.

thanks and boost on

Link to comment
Share on other sites

Yes, propane is a very efficient refrigarant, but I'd never put it in my cars A/C system.

 

Why is that Dan?

 

It is my understanding that There has never been a recorded catastrophic failure of LP refrigerants in automotive use. it is also my understanding that most Taxi cabs in Australia and Germany use some sort of Propane based refrigerant.

 

I would think that If the system would suffer a leak of some sort, that it would be SO SO small and minute that the risk of ignition would be a 1 in a bazillion chance, and even if a large scale failure were to occur, that the small amount of LP (whatever that average system requirements are in ounces) would be nearly dissipated instantaneously.

 

Is there some other reason as to why you would use this type of refrigerant?

Link to comment
Share on other sites

Pure propane gas in a refrigeration system is a prescription for an potential explosion in the event of an auto accident involving the condenser. There is a big difference between "propane based" and a blend containing propane.

 

If you look at the drop in substitutes for R-12, (EPA Approved) Frig C (FR-12) or Autofrost, etc., all of them contain Propane in a mixture below the explosion limit. The idea is to blend the propane with inert items which diminish the explosion potential and not diminish the cooling potential.

 

Check the following link if you are interested in R-416a or Frig C. http://www.refrigerantsinc.com/fr-12.htm

 

IMHO the risk to family, friends and myself is to high for me to use pure propane in my Z and I work with Industrial Refrigeration/compliance on a daily basis. The cost of the substitutes, while higher than R-12 used to be are still doable.

 

Dan has the right perspective, as usual.

 

Ed Palmer/ecp48

Link to comment
Share on other sites

If you want to use 134-A replace all the O-ring seals with silicone seals. Basically black rubber O-rings dipped in Blue silicone is what they gave me. Then it would'nt hurt to get a new compressor since you opened the system or just flush out the old one if it still works. Flush out the whole system with an A/C flush solution to push out all the old oil and whatever contaminants are in it. Then replace with new drier, get a filter if you can, leave the old condenser. When filling up the system make sure you only fill it up 80% of the specification. If you over fill it 134 will actually make it warmer. Since 134 is warmer it would'nt hurt to put an auxilliary fan in front or you could get a bigger condenser, kinda like putting in a 4 row radiator to replace the 2 row.

Link to comment
Share on other sites

  • Administrators
Pure propane gas in a refrigeration system is a prescription for an potential explosion in the event of an auto accident involving the condenser.

Is there not the same risk with vehicle powered by gasoline? 14 - 20+ gallons in a tank in the rear, routed under the car to the engine compartment? What about propane powered vehicles?

Link to comment
Share on other sites

The short answer is No.

 

I don't have the LFL/UFL handy for either gasoline or propane, but if you look at the potential for release (and resultant explosion or flammability), the evaporative condenser is in front of the radiator.

 

In searching for a replacement unit (used) for my Volvo, it seems that almost all of the cars I found had been hit in the front or front quarter and all of them had lost system integrity (refrigeration) in the crash. None of the preceeding appeared to have lost system integrity with regard to the fuel system.

 

Since the Pinto/Vega/Toyota cases of the seventies and early 80s the fuel system is better protected/packaged with regard to crash protection. This is not true of the Refrigeration systems.

 

Further, I believe you will find that the the LFL (lower flammability limit) is lower for the propane (I haven't checked it). Normally when the fuel system explodes, rather than burns, it is because of a spark in the confined space of the tank, the liquid gas just burns. In the case of the propane, it is a pressurized gas/liquid in the system, any breach will result in a volatile and potentially explosive event.

 

If there are any chemists on the site, they could give you a better educated response.

 

Ed Palmer/ecp48

Link to comment
Share on other sites

  • Administrators

Did a little searching and found some interesting info:

Propane has a narrow range of flammability when compared with other petroleum products. In order to ignite, the propane/air mix must contain from 2.2 to 9.6 percent propane vapor. If the mixture contains less than 2.2 percent gas, it is too lean to burn. If it contains more than 9.6 percent, it is too rich to burn.

 

Propane won't ignite when combined with air unless the source of ignition reaches at least 940 degrees Fahrenheit. In contrast, gasoline will ignite when the source of ignition reaches only 430 to 500 degrees Fahrenheit.

 

The odds of a person dying from a direct result of a propane transportation or storage accident involving loss of cargo are about the same as those of getting struck by an airplane falling from the sky.

 

If liquid propane leaks, it vaporizes and dissipates into the air.

 

Link to comment
Share on other sites

Sumo. or Anyone else. So when switching to R-134, you mentioned Bigger condesor. has anyone hung a bigger condensor on their car? and what was it?

 

Well I do appreciate the help .. from all aspects. just wondering what others had done to their Z.

thanks for the help,

boost on

Link to comment
Share on other sites

No i havent hung a bigger condenser and the swap i did was on a different car not a Z. But I can tell you that the coldest i got the car was from being parked in the sun during 98-99 heatwave 130 degrees in the car with the windows cracked open then made a run to the freeway for my next job and it got cold down to 44. During idling in stop and go traffic, however the temps would rise up to 52, a little warm but i had no choice because the R12 even back then would have cost me $900 to be done by a mechanic and i only spent $450 for everything including having a guy vacuum it for me and putting in the 134. I suggest an auxilliary fan in front of the condenser to cool it down more efficiently since 134 is warmer by about 5 degrees in my case. In comparison my 99 Lumina is usually right around 40-42 in 95 degree weather with the stock system built for a 134.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...