Cold AC

OUMike · May 29, 2004

Well after months and months of no AC, its finally done. Although I do regret to inform that I wasn't able to take photographs of the process like I said I would, I did assist in the work that was done. I feel confidant I can answer most any questions about this job. My AC blows in the mid 40s now..burrr. Only problem is my evaporate does in fact have a small leak..bummer. But I try to keep the AC running as easy as it can to prevent condensation into my cab. Its amazing too, because before when my AC worked (or I thought it did) I'd have to run it on high speed fan, max AC all day long in order to get it cool and keep it there. Now I start on high speed fan-max AC and within 5 minutes I'm turning it down. Guess it just goes to show how much a screwy compressor can effect your system.

If someone would like, I can take a few photographs of the finished product and maybe try to put together a how-to. Won't be as effective as if I'd done it during the installation, but I'd be willing to try. Thanks for everyone that helped me here on the board

SteveCZ · May 30, 2004

Thank god mine is still cold.....

But out of curiosity, what did the new compressor run? A few Hundred? Plus the recharge of the gas, obviously..

Also, to keep my compressor running smooth, I've been thinking about going out and buying a can of the oil to keep it oiled up. Is this a good idea or should I just drive it?

OUMike · May 30, 2004

The compressor was a rebuilt unit that ran me about $180 or so. The freon (R-134) ran about $6 a can, and the accumulator ran about $40. Labor was free, because the work was done by a close friend of ours. I spend somewhere in the neighborhood of $220 or so, tax and the whole nine yards.

That could be a good idea. Pull your compressor and accumulator and re-oil your system. If you do this, it'd be a good idea to put a vaccum on your system for a good hour. Then recharge it with about 2.5 cans of freon.

snoman · May 30, 2004

The compressor was a rebuilt unit that ran me about $180 or so. The freon (R-134) ran about $6 a can, and the accumulator ran about $40. Labor was free, because the work was done by a close friend of ours. I spend somewhere in the neighborhood of $220 or so, tax and the whole nine yards.

That could be a good idea. Pull your compressor and accumulator and re-oil your system. If you do this, it'd be a good idea to put a vaccum on your system for a good hour. Then recharge it with about 2.5 cans of freon.

You should never open a R12 or 134 system and not vacum it out. With a new accumulatory/drier there is no need to pull it down for a hour to get moisture out. Just pull it down and hold it for 5 to 10 minutes to confirm that there is no leaks and then charge it up! (assuming that you added/adjusted then needed oil as well too for any component changes)

SteveCZ · May 31, 2004

OK, I'm not quite following you guys here...

My A/C is ice cold still, but I'm just wondering if I can plug a can of the oil into my system's high side or low side (whichever it is, I can't think this early in the morning before coffee).

Let me know

snoman · May 31, 2004

If it is functioning well and not been opened up to loose factory oil charge, there is no need to add to it at this time just for the sake of doing it.

OUMike · May 31, 2004

My A/C is ice cold still, but I'm just wondering if I can plug a can of the oil into my system's high side or low side (whichever it is, I can't think this early in the morning before coffee).

Oil is added directly into the parts. You would have to remove the compressor in order to add oil.

snoman · May 31, 2004

My A/C is ice cold still, but I'm just wondering if I can plug a can of the oil into my system's high side or low side (whichever it is, I can't think this early in the morning before coffee).

Oil is added directly into the parts. You would have to remove the compressor in order to add oil.

Not entirely true. It is possible to loose oil visably through a leak in system and have to add a ounce or two to it to top it off when recharged.

frdfandc · May 31, 2004

Oil is only added during a part replacement. If you have a leak somewhere, that part must be replaced. Or you will continue to waste money in adding oil and refridgerant. In the vehicle service manuals, they have a limit of oil that must be installed per component (lines are usually not included).

But when dealing with either R-12 or R-134a, the a/c system should be evacuated first with a machine, then the system needs to be vacuumed down from anywhere from 3-10 mins, depending on the size of the system. Also, just be cause the system is holding vacuum, doesn't mean there isn't a leak. The leak can appear when pressure is added (recharging the system). You should use a type of U/V dye/oil to verify there are no leaks. This takes the guess work out of replaceing components if there is a leak.

snoman · May 31, 2004

Oil is only added during a part replacement. If you have a leak somewhere, that part must be replaced. Or you will continue to waste money in adding oil and refridgerant. In the vehicle service manuals, they have a limit of oil that must be installed per component (lines are usually not included).

If you have a loose fitting or a bad hose you can lose oil over time with freon requiring a top off. How much of a waste it is depends on size of leak. I had a toyota that I converted to R134 that leaked not quite one can of R134 a year thru a crimped on hose fitting. It cost me less to add a 4 dollar can a year myself than to replace a 75 dollar hose. ( I was not please with conversion anyway but used it to experiment a bit, I will use MP 52 or R12a for any future conversions) You have to take it case by case as there is not 100% solid blanket rule here.

OUMike · May 31, 2004

Also, just be cause the system is holding vacuum, doesn't mean there isn't a leak. The leak can appear when pressure is added (recharging the system). You should use a type of U/V dye/oil to verify there are no leaks. This takes the guess work out of replaceing components if there is a leak.

Good point. However if your holding a vacuum then your leak if definatly elsewhere. My truck held a strong vacuum, but I do have a slight leak inside my evaporator. Those electronic leak detectors are a great investment.

snoman · May 31, 2004

Agreed!

frdfandc · May 31, 2004

Snowman and others who still want to use r-12 in the future.

R-12 is getting very, very expensive. A single LB. of R-12 costs anywhere from $80-$100. If you try and buy a keg (30 lb bottle), they cost around $1500-1800. Also you must be a licensed in HVAC on refridgerant handling (evacuation and storage) for you to even THINK about buying.

Also, within the next 5 years, don't be surprised if R-12 is no longer being made.