Dash AC compressor froze up.

[Acker1]

Troubleshooting my dash AC and found the compressor has froze up. The belt is gone and you can see where it had been slipping.
Compressor---TAMA 488 45018
Expansion valve---134-112
Dryer---Can't find a number.

I have found the compressor listed on some sites, cannot find the expansion valve & the number of the dryer #. Do places sell these 3 items as a kit? Or have to buy them separately? Any ideas on where to find the expansion valve? Dryer #??

Also--amount of R134A & type/amount of compressor oil needed?

Thanks
DICK

[walt2137]

Dick try this link, I know there was 3 different Endeavor, diesel, ford and chevy and the SCS Frigette AC unit could be a little different on them.

SCS / Frigette - Climate Control Products for a World in Motion

[Mike Canter]

The problem is SCS is out of business. I apologise if you know all this already but let me tell you then you can ignore what you don't want.

The receiver dryer is no problem because they are basically all the same. All you have to do is match the fittings and exterior dimensions so it fits. The expansion valve is a little different but the understanding is that they are keyed by the four hose fitting size. So if you get one that will fit all the hose ends then it is going to be close to correct. We do have a guy here that repairs all the MH AC units for John Bleakly RV and he is an expert on MHs. I will be going out to my MH this weekend and will get his phone number for you if you need it. This guy will also tell you what amount of oil you need also.

There are two basic viscosities of refrig oil. You need to make sure that you use the right one for your compressor. There is PAG 46 and PAG 100 oils. You can look up your compressor on this chart and see which oil you need http://www.wrenchead.ca/pub/PAG_oils_application-05.pdf One thing I learned is that if it is a Sanden compressor it takes PAG 100 and all other compressors take PAG 46. The instructions that come with the compressor should tell you how much to put in it. Warning here. Drain all the oil out of the compressor and put in the correct amount of oil. They are know to be off on the amounts.

The unit is going to take around 4 lbs of R-134 maybe even 4.5 lbs but normally you want to put in a lesser amount and then hook up gauges to read low side and high side pressure. Then you read the temperature of the air going into the evap coils and use this chart to know what pressures you need. All R-134a systems use the same temp to pressure charts. You can buy a can of freon that comes with the pressure gauge and chart from an automotive parts store.
R134a Refrigerant Pressure Temperature Calculator

One thing that you need to do with that system is to flush it out the whole system with AC flush because if the compressor froze up then you are going to have small metal pieces in the whole AC system. You will probably need about a gallon of flush. You pour it into and open hose and blow it through with compressed air. I normally blow it until it starts coming out the other end then stop and let it sit awile then blow it out again and do this several times. Once clean I leave the air hose attached an blowing for about 10-15 minutes to make sure it is dry.

I guess you know that you are going to have to evacuate the system?

[Acker1]

Mike--Thanks for the links and info.
"The expansion valve is a little different but the understanding is that they are keyed by the four hose fitting size. So if you get one that will fit all the hose ends then it is going to be close to correct."
That confuses me--I only see an input, output fitting & 2 small copper tubings coming out. The numbers on it are 134-112 & 1557C.

DICK
Currently in Richmond Hill, Ga.

[Barlow46]

Originally Posted by Mike Canter

The problem is SCS is out of business. I apologise if you know all this already but let me tell you then you can ignore what you don't want.

The receiver dryer is no problem because they are basically all the same. All you have to do is match the fittings and exterior dimensions so it fits. The expansion valve is a little different but the understanding is that they are keyed by the four hose fitting size. So if you get one that will fit all the hose ends then it is going to be close to correct. We do have a guy here that repairs all the MH AC units for John Bleakly RV and he is an expert on MHs. I will be going out to my MH this weekend and will get his phone number for you if you need it. This guy will also tell you what amount of oil you need also.

There are two basic viscosities of refrig oil. You need to make sure that you use the right one for your compressor. There is PAG 46 and PAG 100 oils. You can look up your compressor on this chart and see which oil you need http://www.wrenchead.ca/pub/PAG_oils_application-05.pdf One thing I learned is that if it is a Sanden compressor it takes PAG 100 and all other compressors take PAG 46. The instructions that come with the compressor should tell you how much to put in it. Warning here. Drain all the oil out of the compressor and put in the correct amount of oil. They are know to be off on the amounts.

The unit is going to take around 4 lbs of R-134 maybe even 4.5 lbs but normally you want to put in a lesser amount and then hook up gauges to read low side and high side pressure. Then you read the temperature of the air going into the evap coils and use this chart to know what pressures you need. All R-134a systems use the same temp to pressure charts. You can buy a can of freon that comes with the pressure gauge and chart from an automotive parts store.
R134a Refrigerant Pressure Temperature Calculator

One thing that you need to do with that system is to flush it out the whole system with AC flush because if the compressor froze up then you are going to have small metal pieces in the whole AC system. You will probably need about a gallon of flush. You pour it into and open hose and blow it through with compressed air. I normally blow it until it starts coming out the other end then stop and let it sit awile then blow it out again and do this several times. Once clean I leave the air hose attached an blowing for about 10-15 minutes to make sure it is dry.

I guess you know that you are going to have to evacuate the system?

Mike,
Help me out here with the Calculator. If I have R-134 and my system holds 4 lbs and the ambient temperature is 92 F what should my high side and low side read on my gauges? Not sure if I need to add the 14.7 as a constant. Thanks

[Mike Canter]

Don't know where your 14.7 comes from. For filling the most important thing is your low side pressure. The high side is wide on its range and usually only used for troubleshooting. It is NOT ambient air temp you need but the tem of the air going into the evap which is uuasully under the front of the MH if a diesel pusher or in front of the radiator for a gas motor in the front. For 92*F the pressure should read 107.52 psig and the high side should be between 165 and 270 psig. If the low side is low then add R-134a if high then bleed it off a little.


Acker1, yes there are two designs for expansion valves. I have a four hose expansion valve. Why do you think the expansion valve is bad? The sure way to tell is to have the compressor working and you will show a super low psig on the low side and a super high psig on the high side. Like I said I will get you the phone number for this MH AC expert and you can call him Monday and he will tell you exactly what expansion valve to use. If you are coming through Marrietta, GA just NW of Atlanta you can get this guy to fix or I will take you to an AC parts warehouse that can get you everything at a pretty good price.

I am not absolutely sure but I think that expansion valve number 134-112 is really 134- 1 1/2 meaning one and half tons

[Acker1]

Mike--I'll Google that number and see what I get. I was thinking that the expansion valve should be replaced when replacing a frozen compressor, along with the dryer and flushing the hoses.

Does the warehouse you mentioned ship? what is the name/website?

Will you PM me the phone # of the AC expert? Just in case I need it.

Thanks
DICK

[Mike Canter]

The place for parts is Marietta Radiator phone 770.428.5900 and I just talked to them and they do ship parts. The place to fix your AC is Wizards Automotive. The guys name is Donald (the Wizard) and they are just down the road from John Bleakly RV (Fairburn Rd). Donalds place is on Gurley Rd which is close to downtown Douglasville just off of Bankhead Highway. The address is 8841 Gurley Rd, Douglasville, GA and his phone is 770.489.5567.

I just talked to Donald and he said yes you need to change your expansion valve if you had a compressor freeze up but the most important thing he said is to flush out that system or it will fail again. He also said that I was correct on the expansion valve being 134-112 being for a ton and a half unit.

If you are going to come this way and need assistance then feel free to give me a call at 678.777.3672.

I have to warn you that the dip going down into Donalds place is a little steep. Because my Signature sits so low I had to raise my air suspension so I didn't hit my trailer hitch.

[Acker1]

Mike--
I have to put this project on hold for a week. Death in the family and I have to go up to the Catskill Mtns, NY. Leaving the MH here (Richmond Hill, Ga) and just driving my truck up there.
Thanks for all the info and I'll update you when I get back.
DICK

[Mike Canter]

Dick, I am sorry to hear that. Please accept our condolences.
Anytime you are ready to start up again and you want help then you have my mobile number and my email is mike.c@mindspring.com

[Acker1]

Mike--When I got back here, my nephew & his friend (certified mechanic with proper AC tools) had replaced, flushed, charged--did everything. It's working great. I am parked in his driveway and they just decided to do it.

Thanks you for all your help.

DICK