Air Conditioning.

[BIGdaddy]

Well, the temps are already rising here in san diego. (used to be 30-40 degree's at 5:30 when I'm leaving for work...now its 50-60)

I suffered through not having A/C last summer, since I had just got my truck,and was happy to simply have a good car to get to work in. Just not feelin' like roughing it through 107 degree heat spring/summer. :sombrero:

To that end, I went today and got a quote of about $150.00 to convert my r12 system to r134, discharge the system of the old freon, and re-charge with r134...

My system now is showing bubbles, which, to me, means that I have air in my system and not enough pressure to even turn on the compressor, though the blower works...

Does this sound about right? buck-fifty to get it converted,and then maybe more work if it doesn't blow cold after the install?

 

[StumpXJ]

Im not sure about the work being done being worth the money, as A/C is something I know very little about. BUT, I would gladly pay 150 bucks not to have to ride around in a hot vehicle all summer... They dont call it Hotlanta for nothin. I would imagine its the same in your neck of the woods.

 

[rambrush]

To convert it they will have to remove the R-12 and change a few parts. While they are drawing it down they should let it sit on vacuum and confirm no leaks. If the system has not been used in quite awhile the compressor shaft seal possibly will need to be replaced. But all connecting points will need a visual to see if there is a accumulation of oil and dirt indicating a possible leak point.
You are correct in that seeing bubbles should indicate system is low on freon. So maybe the system is actually holding pretty well just a small seepage from not being used in quite awhile.

Well, the temps are already rising here in san diego. (used to be 30-40 degree's at 5:30 when I'm leaving for work...now its 50-60)

I suffered through not having A/C last summer, since I had just got my truck,and was happy to simply have a good car to get to work in. Just not feelin' like roughing it through 107 degree heat spring/summer. :sombrero:

To that end, I went today and got a quote of about $150.00 to convert my r12 system to r134, discharge the system of the old freon, and re-charge with r134...

My system now is showing bubbles, which, to me, means that I have air in my system and not enough pressure to even turn on the compressor, though the blower works...

Does this sound about right? buck-fifty to get it converted,and then maybe more work if it doesn't blow cold after the install?

 

[chasespeed]

Well...ASSUMING you know nothing about A/C....

Bubbles in the sight glass, indicate non-condenseables., i.e. air and moisture in your system, or a low charge.

Anyway, it is unlikely that you still have refrigerant in the system, AND air got in, at 20*, R22 is at 42psi, and at 80*, its at 145psi.

IF you have refrigerant, and the compressor, wont start, it could be EITHER the low pressure switch, or the high pressure switch, both protect the compressor. (most likley a low pressure switch isnt closed, preventing the compressor from operating)

IF there is no pressure at all in the system, and there are bubbles, yes, you have moisture/air.

Any of these can be solved, BUT, you should check all hoses, and fittings for any signs of leaks... a film of oil is a good indicator of a leak.

IF the system has been exposed to atmosphere for any length of time, you are going to want the filter drier changed. The rest will be solved by putting it under deep vacuum.

The oils in R22 and 134a are different as well as the operating pressures...

If they say they will have your A/C running for 150.... let'em do it......

Chase

EDIT: I will leave the info, but, I must have misread the R12 vice R22( I do residential, and commercial stuff, so, only R12, and 134a I come across is in reefers, and such)

 

[iflypropjobs]

Ditto what Chasespeed said - I would add that if you have any nitrogen available - pressure the system up to around 150psi & do your own leak check with some soap bubbles - it will save you some cash if you replace o-rings & such by yourself. Fixing the "extras" is where all the shops around here make their money on the refrigerant conversions.

Good luck with - 4 wheeling with AC is the only way to fly!

 

[cruiser guy]

The conversion for $150 is a good deal in my books. Let us know how it works. I'd also be interested in the shop 'cause I'll need to have mine recharged and a new dryer and I was going to do it in Mexico but for $150 I'd do it stateside.

 

[Deleted member 13060]

$150 for an A/C conversion = an illegal hack job!!!!! Remember if it sounds too good to be true..... it probably is.

The bare minimum for a legal/correct job would entail a reciever dryer, a complete system flush and a new pressure switch. The oils that are carried by the freon to lube the system are NOT compatible with the old oil and MUST be completely removed. Even so a compressor failure down the road is most likely in the works.

R-134 is nowhere near as efficient as R-12 and functions best at much higher pressures. Your old R-12 parts might not be up to the task. Your old "smaller" (remember 134 is not as efficient) condenser might need to be changed to a newer one designed for 134 in order to cool as well as it used to.

The chances of an old R-12 system holding R-134 for a year are slim to none. 134 molecules are approx 1/2 the size of R-12 molecules and a "tight" R-12 system might (and probably will) leak like the proverbial sieve.

Also STAY AWAY from any replacement freon that isn't 100% R-134. A lot of these "replacement" products use flammable gasses as a carrier. Such as PROPANE!!! If you want a leak in your system to blow propane into either the engine compartment or the passenger area, be my guest. I've seen an old Ford Pickup that was convereted with some crap with propane in it. The cans were in what was left of the bed. Long story short, what should have been a fender bender killed the driver when the a/c system ruptured in the engine comp. There was a piece of shin bone under the gas pedal!!!!!

Sorry to be a party pooper and so negative. Do it right once and be done with it...... RON

 

[chasespeed]

That catch is, Propane is an excellent refrigerant.

I would have to say that there was more that an propane involved in that. Considering most small A/C systems, use around 2lbs of refrigerant, so.. how much LPG could really be in there? There just isnt wouldnt be enough LPG in there to have more than a flash over, IF that....certainly not enough to cause an explosion.

We have a LOT of vehicles in our company that are FUELED by propane, which put more propane into the engine compartment, than would certainly be contained as a thinner in a vehicle A/C.

That said, I wouldnt use it anyway, I always try to use virgin refrigerant when I can.

No