thebird00
1/2 ton status
I have a huge A/C in my M1010 CUCV ambulance. With the A/C on, the relay for it constantly clicks. Is this normal?
CK5
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Constantly Clicking Relay
- Thread starter thebird00
- Start date
thebird00
1/2 ton status
I asked about this on steelsoldiers.com. One person suggested it may be low coolant and the low pressure switch was kicking on and off.
mdm365
1/2 ton status
pressure switch
There is a pressure switch that will cause it to cycle on off because it is
1.Low on freon
2.Bad pressure switch
You can jump the 2 wires to see if it will stop cycling,I did this on the old r12 systems when I was doing service to it because it will cycle when adding freon because the gauges would fluctuate.If it is low on freon I would look for leaks.If that's the case they will have to be fixed and the system will have to be evacuated before it's recharged.
I would try to add some r12 if you can get it or it will have to be converted to 134a that will require some other changes to the system to be right.the pressure switch typically looks like this.
Hope it helps!!! Mike
There is a pressure switch that will cause it to cycle on off because it is
1.Low on freon
2.Bad pressure switch
You can jump the 2 wires to see if it will stop cycling,I did this on the old r12 systems when I was doing service to it because it will cycle when adding freon because the gauges would fluctuate.If it is low on freon I would look for leaks.If that's the case they will have to be fixed and the system will have to be evacuated before it's recharged.
I would try to add some r12 if you can get it or it will have to be converted to 134a that will require some other changes to the system to be right.the pressure switch typically looks like this.
Hope it helps!!! Mike
thebird00
1/2 ton status
Thanks for the info Mike. The guy I bought it from "said" he had it blowing cold last summer after he had some work done to it. If I have to pay to convert it then I'll probably just run with the windows down. I'm gonna check that pressure switch if I can find it just to make sure.
thebird00
1/2 ton status
Ok. There was zero coolant in the system. I'm suspecting a leak, but I have picked up 6 cans of Freeze 12. It's supposedly a replacement for R-12. No license required to buy it. Now I just have to get a set of gauges with the right fitting.
I also picked up 8 oz of oil. The guy told me 2 oz should be enough for the whole system.
I also picked up 8 oz of oil. The guy told me 2 oz should be enough for the whole system.
mdm365
1/2 ton status
evacuate the system first,For one you will know if you have a leak.The second is evacuating the system will remove all the air from the system and some contaminates.If this is not done you will most likely have an issue with getting the full amount of freon in the system this is because it will create a vacuum(if you will) to pull in the freon charge.It will pull some in in most cases it wont.Make sure the freon does not have oil added to it if there is to much oil in there it will cause issues.
Mike
thebird00
1/2 ton status
How do you evacuate the system?
mdm365
1/2 ton status
You will need a vacuum pump like this http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=92475
and a set of gauges like these http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=92649
These are from harbor freight.Now the gauges there are for 134a freon could not find them in r12 but you might find an adapter for them.
now you could pull the system down with just the pump but it will be hard to tell because the ac gauges have a grid on the dial that tells you if the vacuum is pulling down,This is also how to test for a leak because it will show on the gauges that the vacuum is 1 not pulling down 2 vacuum will not hold on gauges.
If you end up with the last one there are 2 things to do here look around the system ie compressor,lines,condenser ect for wet areas.I have found the most common place for a leak is the compressor.
The other is to put in as much freon as you can and see if its leaking sometimes you can see it other times you can't you will have to use a die in the system or sniffer like this http://www.harborfreight.com/cpi/photos/92500-92599/92514.gif
You might check auto zone or a buddy to see if they have some of these tools you can barrow,It,s not that hard to do but the equipment is the worst of it.
Hope it helps,like I said the tools referenced are hf tools(cheep)I have used some of this stuff and had good results. Any more questions just ask! edit--I foud something else that might help you http://www.redhillsupply.com/how-to-vacuum-pump-ac.htm
Mike
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thebird00
1/2 ton status
This is really good info. I'm hoping I can borrow a set of gauges and rent the pump. I have been told that all you really need to do to convert this system to 134a is change the fittings and get all the R12 out.
Most folks say that you have to change the drier and the compressor. Anybody know if you can get by with just changing the fittings? I'm just trying to get some cold air for a fishing trip Monday that is about a 2 hour drive. After that I could look further into the possibility of a leak, which I'm sure is present.
Most folks say that you have to change the drier and the compressor. Anybody know if you can get by with just changing the fittings? I'm just trying to get some cold air for a fishing trip Monday that is about a 2 hour drive. After that I could look further into the possibility of a leak, which I'm sure is present.
thebird00
1/2 ton status
One more question. If I evacuate the system and add the first can of coolant, what do I do for the rest of the cans?
Do I just shove them in there behind the first?
Do I just shove them in there behind the first?
mdm365
1/2 ton status
Ok after reading through this some more I see you have a M1010 CUCV ambulance,Does this have rear ac(separate form the front) or is it all the same unit??
The reason I ask is It will most likely take more freon to charge it because most vehicle's that have and extended ac(if you will) will have a second evaporator and fan for the rear unless it's 2 separate units.
One more question. If I evacuate the system and add the first can of coolant, what do I do for the rest of the cans?
Do I just shove them in there behind the first?
Yes! just follow with the rest
Most folks say that you have to change the drier and the compressor. Anybody know if you can get by with just changing the fittings? I'm just trying to get some cold air for a fishing trip Monday that is about a 2 hour drive. After that I could look further into the possibility of a leak, which I'm sure is present.
I have done both,There is times were a person does not have much money to do both.I would change the dryer and clean out the old oil from compressor from the (r12 )because it's not very compatible,the dryer will trap contaminates and moisture from the old r12and not easy to flush because it has a sack in it to trap the moisture and such,Then adapt the ports. What I have found is the radial compressors handle 134a well the york compressors don't like the higher pressers the 134a creates.Make sure all the lines are not swollen (rotten) they will pop.
As for Monday it will be nice to have ac for sure ,With you there!! You stated you have some freeze 12?? This is the replacement for r12,There is no other things to be done is the unit is in good shape.You could try to put it in and see what happens you might get lucky just for your trip although I would still try to evacuate it first it just makes it easier.
Just a thought, r12 is very expensive not an option, freeze 12 is out there and hard for me to find at this time and the price is not bad.134a is every were and cheep that's why there is a lot of conversions done in West Virginia
Mike
The reason I ask is It will most likely take more freon to charge it because most vehicle's that have and extended ac(if you will) will have a second evaporator and fan for the rear unless it's 2 separate units.
One more question. If I evacuate the system and add the first can of coolant, what do I do for the rest of the cans?
Do I just shove them in there behind the first?
Yes! just follow with the rest
Most folks say that you have to change the drier and the compressor. Anybody know if you can get by with just changing the fittings? I'm just trying to get some cold air for a fishing trip Monday that is about a 2 hour drive. After that I could look further into the possibility of a leak, which I'm sure is present.
I have done both,There is times were a person does not have much money to do both.I would change the dryer and clean out the old oil from compressor from the (r12 )because it's not very compatible,the dryer will trap contaminates and moisture from the old r12and not easy to flush because it has a sack in it to trap the moisture and such,Then adapt the ports. What I have found is the radial compressors handle 134a well the york compressors don't like the higher pressers the 134a creates.Make sure all the lines are not swollen (rotten) they will pop.
As for Monday it will be nice to have ac for sure ,With you there!! You stated you have some freeze 12?? This is the replacement for r12,There is no other things to be done is the unit is in good shape.You could try to put it in and see what happens you might get lucky just for your trip although I would still try to evacuate it first it just makes it easier.
Just a thought, r12 is very expensive not an option, freeze 12 is out there and hard for me to find at this time and the price is not bad.134a is every were and cheep that's why there is a lot of conversions done in West Virginia
Mike
thebird00
1/2 ton status
It just has the large unit for the rear. Nothing up front.
I hit autozone today and rented a vacuum pump and a set of gauges. I bought the conversion kit which is just basically the fittings, 3 cans of 134a and a cheap gauge to fill with.
I could never get my hands on a set of gauges to put the freeze 12 in with.
Thank you for the time you have spent explaining this stuff to me. Your info has been great.
I have 50 oz total of 134a. I should have bought another can or two, but I'll just run back to autozone if it's not enough. Thanks again.
I hit autozone today and rented a vacuum pump and a set of gauges. I bought the conversion kit which is just basically the fittings, 3 cans of 134a and a cheap gauge to fill with.
I could never get my hands on a set of gauges to put the freeze 12 in with.
Thank you for the time you have spent explaining this stuff to me. Your info has been great.
I have 50 oz total of 134a. I should have bought another can or two, but I'll just run back to autozone if it's not enough. Thanks again.
mdm365
1/2 ton status
Mark, no problem glad I could help!! Any time!
I could never get my hands on a set of gauges to put the freeze 12 in with.
This is also getting to be and issue they are hard to find unless someone wants to spend alot on them,like snap on ect.
Have fun Fishing wish I could go,To much to do around here just moved and cant' find any thing!!
Mike
thebird00
1/2 ton status
It'll be my first 2 days off in over a year so I hope the fish are biting.
