I have been trying to get my A/C to work properly but the clutch won't engage on it's own. I have recharged the system with Red Tek 12a and jumped a direct 12volts to the compressor clutch and it blows nice and cold. I have got power all the way down to the compressor clutch conndection but I am getting no ground for some reason. If I ground it with a jumper wire the system works fine but will not ground on it's own. There are 2 wires coming from the back of the compressor and I'm not sure what they are all about. One is a high preassure cut out and the other I'm not sure about. Anyone got any ideas?

Dave

WTF is red whatever???

www.redtek.com seems to only be avalible in Tennessee in the US. Many dealers in Canada.
from their site: "RED TEKŪ 12a, a HC-based refrigerant from Thermofluid Technologies, is a blend of environmentally safe hydrocarbon fluids designed as a direct replacement and retrofit refrigerant option for replacing R134a and R12 refrigerants in automotive air conditioning and refrigeration systems. 12a operates at lower head pressures and offers improved cooling properties and performance verses R134a and R12."
Hmm, not real clear on what it means...
"Compatibility: Compatible with most common refrigeration materials and lubricants including R134a, R12, metal components, mineral and synthetic(Ester and PAG) lubricants, seals, gaskets, hoses, compressors, and o-rings.
* Safety: Does not become caustic when contaminated with moisture or oxygen. Non-toxic, non-carcinogen, autoignition temperature above 1385F. No long term health risks have been attributed to RED TEKŪ 12a refrigerant."
It's and HC zeoptrope composition, whatever that means. Seems to me just another R12 alternative, like freeze 12.

quote Originally posted by Dave E Bouy: One is a high preassure cut out and the other I'm not sure about. Anyone got any ideas?

The high preasure cut out switch is either unplugged or bad.

It's Flammable.

I really wish people wouldn't use stuff like this - it's a flammable gas and could turn a small accident into a much worse situation.

But since you've already done it: This gas mixture operates at a much lower pressure than R-12 did - the low pressure cutout switch isn't seeing enough pressure to allow the compressor to operate. The low pressure cutout switch is screwed onto one of the fittings on your accumulator (silver tank under the hood); pull the connector and jumper it to see if this allows the compressor to start. If so, you can try adjusting the switch (not a great idea) or get a switch that's calibrated for this mystery mixture.

quote Originally posted by USFiero: www.redtek.com seems to only be avalible in Tennessee in the US. Many dealers in Canada. from their site: "RED TEKŪ 12a, a HC-based refrigerant from Thermofluid Technologies, is a blend of environmentally safe hydrocarbon fluids designed as a direct replacement and retrofit refrigerant option for replacing R134a and R12 refrigerants in automotive air conditioning and refrigeration systems. 12a operates at lower head pressures and offers improved cooling properties and performance verses R134a and R12." Hmm, not real clear on what it means... "Compatibility: Compatible with most common refrigeration materials and lubricants including R134a, R12, metal components, mineral and synthetic(Ester and PAG) lubricants, seals, gaskets, hoses, compressors, and o-rings. * Safety: Does not become caustic when contaminated with moisture or oxygen. Non-toxic, non-carcinogen, autoignition temperature above 1385F. No long term health risks have been attributed to RED TEKŪ 12a refrigerant." It's and HC zeoptrope composition, whatever that means. Seems to me just another R12 alternative, like freeze 12.

RED TEKŪ 12a refrigerant - another creative name for propane/butane mix. At leastt some of the purveyors of these products include odorants so you can smell a leak. Most don't.

[This message has been edited by sanderson (edited 07-05-2005).]

I agree with Electrathon. If there is voltage at the clutch, the accumulator switch must be closed, or you have a V5 compressor. If it’s a DA/HR6 compressor, one side of the clutch winding is grounded through the high pressure cut out switch in the compressor body. If you have a V5 compressor, the high and low switches are both in the compressor body and they are connected in series to ground. Either way it sounds like either a switch is bad (unlikely) or the wiring around the clutch or switch(es) is bad.

The Red Tek site video is a bit scary. No need to pull a vacuum? Put the stuff in with the engine running and use no eye protection? And how come the woman was so much cooler after she turned up the temperature control?

Also wonder why a Tennessee company is sending pine scented butane to Canada? Maybe orange or lemon fragrance would be more noticeable.

I really wish people would not put a flammable gas into an 18 year old leaky air conditioning system. That just scares me thinking about it. R134a is not a drop in replacement, but it works well enough. And the vapors won't ignite.

Anyway to answer your question you are only charging to 33% of R12. You are going to have to bypass your low pressure switch. But if your refrigerant leaks out your compressor is toast, but it won't matter because the entire car is going to be toasty warm from the fire.

Ach you guys worry too much. The way I see it the if the product did not meet Canadian Safety Standards they would never have allowed the product to be marketed in the first place and in my experience the Canadian Safety Standard guys are pretty doggone sticky. In any case the deed is done. I honestly do appreciate your concern, but I don't feel particularly threatened by the fact that the system has flammable gas in it. If there is a leak it would take an open flame or spark to ignite it and even then it's very unlikely that the leak would provide enough gas to sustain a flame unless the leak were sudden and all at once and then we're still only talking about 16 ounces of ignitable gas. On the other hand I still haven't solved the electical issues with the clutch yet but I suspect the High Pressure Cut-out Switch as well. When and if I do get the system running I'll let ya know how it works out. Thanx for all the input.

Dave

quote Originally posted by spark1: I agree with Electrathon. If there is voltage at the clutch, the accumulator switch must be closed, or you have a V5 compressor. If it’s a DA/HR6 compressor, one side of the clutch winding is grounded through the high pressure cut out switch in the compressor body. If you have a V5 compressor, the high and low switches are both in the compressor body and they are connected in series to ground. Either way it sounds like either a switch is bad (unlikely) or the wiring around the clutch or switch(es) is bad.

So is it possible to replace these switches? I've pretty much determied that that is where the trouble is! When I jump a wire from the wire that goes to the High Pressure Cut-out Switch to a known ground the clutch engages! I have 2 leads running into the back of my compressor so can I assume that this is the V-5 compressor? If not what is the other wire for? It has a little probe that sticks into the compressor itself and clamps onto a flange of some sort! Any help appreciated. . .

Dave

The switch is held into the rear of the compresser by an snap-ring. The refrigerant needs to be evacuated. The snap ring removed, the switch pulled out, the o-ring seal replaced and a new switch installed.

The stuff you have in it is literally a bomb. I can not suggest strongly enough that yu should fix this properly! I know, for many years people carreid dynomite around in the back of thier wagons, and only some of them died. That still did not make it safe! It is not that hard to do a proper conversion to 134A, it will work for years and be safe at the same time.

The second wire on the compressor is the radiator fan switch. The fan should turn on whenever the A/C is on. Switch info and part numbers are here.

If you put that stop-leak stuff in the first time don’t add it again when you recharge. Also, get a set of gauges. That’s the only way to tell how well your system is working.

I really don’t know how dangerous it is to use hydrocarbon refrigerants. In Arizona it’s use is banned. In all the surrounding states except Utah, it’s legal (to replace R134a only, a federal rule). Haven’t heard any news stories of California cars blowing up due to hydrocarbon refrigerant use. I think it’s most dangerous to people servicing the units.

My alt-fuel work vehicle carries 26 gallons of propane plus 20 gallons of gasoline and that concerns me more than what’s in A/C system. The propane tank has vented a few times while parked in the sun and that’s scary.

Thanx guys. I know a lot of people are concerned about the hydrocarbon refrigerants and I honestly have not decided wether or not it stays or goes. I hate to just blow it off (thats a joke) because it blows soooooo nice and cold and it's a cheap fix. What is involved in converting to 134a and more importantly can I do it myself? I will likely leave this stuff in for this season anyway and if it's not too expensive add it to my list of things I want to improve over the winter! Many thanx to all all who piped in!

Dave

BTW Spark1 love the link you gave me, I've bookmarked it for future use!

[This message has been edited by Dave E Bouy (edited 07-12-2005).]

quote Originally posted by spark1: The second wire on the compressor is the radiator fan switch. The fan should turn on whenever the A/C is on. Switch info and part numbers are here.

Thanks for the info! I spent the WHOLE day looking for replacments for the fricken switches on the back of the compressor. Turns out they have been replaced with "new style" ones that have a different TWO PIN connector and need to be grounded externally. What pisses me off the most is that NO ONE's inventory had any one pin switches, and none of the two pin ones stated that they were a replacment substitute. Even the dealer had a difficult time helping me out. But that little bit of info is going to save me from tearing my hair (what little I have left) out. Curious, why is there a fan switch on the back of the compressor if the fan turns on with the A/C button on the controls? Redundant in case of failure like the fuel pump system?

Shoulda looked here first.

I can easily see why they replaced the switches with two wired ones. The only ground on the one wire ones was the rubber O-Ring, and the spring clip, neither of witch are all that great for grounding, and can easily render a AC system inoperative. But you heard it here, There are no 1 pin replacments available anymore, and you should get the two wire.

BTW, it is 113° F outside today. And my AC don't work... yet.

[This message has been edited by Fierobsessed (edited 07-13-2005).]

If you're switching refrigerants, make sure you are using compressor oil that is compatible with whatever you're doing ....

quote Originally posted by Dave E Bouy: Thanx guys. I know a lot of people are concerned about the hydrocarbon refrigerants and I honestly have not decided wether or not it stays or goes.

Something to think about, which is what prompted me to stay away from the flammable over-the-counter replacements.

Your a/c system has two shraeder valves in the front compartment. They are common sources of leaks.
You also have the HVAC blower motor up there, which is a run-of-the-mill DC motor which uses brushes. I have yet to see a (brushed) electric motor which does not have some measure of arcing taking place between the brushes & commutator when it's running.

Flammable refridgerant vented in to a relatively enclosed area which also contains a spark source = as far as I'm concerned.

quote What is involved in converting to 134a and more importantly can I do it myself?

The Ogre's Cave has a good article on this under the Interior->HVAC section. If you have the right equipment, all you need a shop for is to evacuate the old refridgerant, properly flush the system, and recharge it after you've replaced the necessary components. Note however though that since you now have a mix of R12 & hydrocarbon refridgerants in there, some shops may refuse to evacuate the system for you.

quote Originally posted by dguy: Note however though that since you now have a mix of R12 & hydrocarbon refridgerants in there, some shops may refuse to evacuate the system for you.

I thaught it was a legal requirement for a licienced AC service facility to recover ANY refrigerants? At least in Nevada Im pretty sure it is. But I can't say for elsewhere. Plus, what they dont know... YOU know. Heh, another good quote by me.

quote Originally posted by Fierobsessed: I thaught it was a legal requirement for a licienced AC service facility to recover ANY refrigerants? At least in Nevada Im pretty sure it is. But I can't say for elsewhere. Plus, what they dont know... YOU know. Heh, another good quote by me.

They're legally required to recover refrigerants. They're not legally required to work on your car.

Many shops have analyzers to detect refrigerant composition to avoid contaminating their recovery systems. The recovery systems have to be dedicated to a certain refrigerant. Once you venture outside the R-12 and R-134a arena, it's going to be tough to find a shop with a recovery system.

quote Originally posted by Fierobsessed: Curious, why is there a fan switch on the back of the compressor if the fan turns on with the A/C button on the controls? Redundant in case of failure like the fuel pump system?

May be for redundancy but also turns on the engine fan when "defrost" is selected on the V6's. The L4's are wired to turn on the engine fan for any A/C setting or defrost. For some reason the defrost setting on the V6 models doesn't turn on the engine fan directly, even though the A/C clutch engages.

quote Originally posted by Fierobsessed: But you heard it here, There are no 1 pin replacments available anymore, and you should get the two wire. BTW, it is 113° F outside today. And my AC don't work... yet.

Advanced auto has them listed

http://www.partsamerica.com/ProductDetail.aspx?mfrcode=FAA&mfrpartnumber=35962&parttype=432&ptset=A

Good luck, hope this saves some of your hair!

Dave