THINK!! before removing your factory A/C!

[magnakansas]

well,

That is one I've never heard of before. And now I have.

Once again I learned something new.

Thanks for the pictures.

william

 

[cadillackid]

That is one I've never heard of before. And now I have.

Once again I learned something new.

Thanks for the pictures.

william

the first time i saw one i thought it was a total hack, then I emailed TRANS / AIR and they said there were some ,made like that.. I didnt really Like the design

but i guess the result is the same, provide a column of cool liquid to the expansion valve and its going to blow cold...

 

[B1GF00T.III]

I was going to call them today to see if I can get some more info before starting on this thanks guys

 

[B1GF00T.III]

Flare nut sizes for condenser

Cadillac Kid would you happen the know if the liquid line and suction line on that duel condenser are a flare nut style thread .If so what size ? Pressure tested and held steady for over a week now. I was going to disconnect one side (non-driver side) evaporator . Then depressurize the system ?

 

[cadillackid]

Cadillac Kid would you happen the know if the liquid line and suction line on that duel condenser are a flare nut style thread .If so what size ? Pressure tested and held steady for over a week now. I was going to disconnect one side (non-driver side) evaporator . Then depressurize the system ?

the fittings on mobile A/C are O-ring type fittings.. if its pressurized with refrigerant you need to recover it.. if its just nitrogen then you want to depressurize via the schraeder.. on an O-ring fitting loosening the nut wont always cause a leak-down.. the O-ring mauy be somewhat stuck so if you take the nut off then the line can pop off and spray oil / gas violently...

 

[magnakansas]

butting into the conversation

yes, CadillacKid is right on. as usual.

william

 

[B1GF00T.III]

I would open the high and low side on my gauges then blow it down through the yellow common hose. We would call that a purge . I was referring to the condenser on the drivers side of the bus where the four hoses ( 2 low side & two high sides) are attached .

 

[B1GF00T.III]

I think this may be a 5/8 MPT . I was going to use leak lock and a flat brass cap.

 

[B1GF00T.III]

That first question should have read repressurize not depressurize

 

[B1GF00T.III]

Decide not to take down one evaporator the bottom compressor goes to the drivers side evaporator the top compressor goes to the non drivers side. Pressure test has not drop for a week it’s held steady . Purged the nitrogen . Currently the vacuum pump is pulled down to 510 microns. Turned off pump to see is resting pressure 690 mics. I’m just going to weigh in 6 lbs if 134-A and run it .those condenser fittings look like AN female caps .( still not sure) first time work on a 91 blue bird AC.

 

[cadillackid]

Interesting on those fittings . They are supposed to be O ring but the hose side does look like AN ..

For 134a 690 microns is more than good. Love seeing someone who knows how to work on this stuff!!

 

[B1GF00T.III]

Pulled it down again to 500 microns . Turned it off that’s was it’s sitting for about 15 minutes. More too follow

 

[Big dog-SKO]

once you take the inside plastic covers off you'll find that the evaporator and fan unit isn't all that big. so reducing the "cabinet size" will not be so invasive to the interior space. just remember it has to have proper air flow so don't restrict air movement and you'll be fine.

 

[ChurchBuz]

Thanks guys!

I really appreciate y’all’s help with my AC

I take this thread to heart and want to save the factory AC if feasible. Alas the guy I bought it from said that “it never worked right, and that everyone and their brother tried to fix it”.

They obviously never had skoolie powered resources

 

[cadillackid]

this firum is really getting on my nerves.. all their Ads with auto refreshing the oage has wiped out several posts of mine lately..



so here I start again.. only unfortunately this time im not going to be as detailed..


I have fixed and seen a LOT of ill - maintained school bus A/C systems.. bus fleet / garage managers may be great for oil changes and keepign the tires pumped but they generally suck at A/C..


1. dirty coils inside and out.. (outside coils need checked on both asides of the fans.. as do inside coils,, dirt kills capacity..)


2. bad condensor fans or cheapie chinese ones.. most of the condensors can take SPAL fans and those are the only brand i use..



3. non condensables.. - a system gets a leak and someone tries to recharge it with automotive A/C cans.. (first off make sure the system has been converrted to 134a and isnt still expecting R12 (some busses require R22 back in the day)..



when someone recharges with cans they often install multiple cans with stop-leak and / or tracer dye and sometimes oil charge,,



over and over again this is done instead of a leak being properly repaired and now you have all kinds of Liquids inside the freon pipes that reduce the ability of the unit to cool.. or cause intense head pressure buold which cycles out the comporessors on high-pressure over and over..



the result is a system that seems full of refrigerant and yet wont cool for crap..


I dont know much about your particular system so its hard to say exactly whats wrong.. if you were close by me im sure we could figure it out pretty easily..

 

[ChurchBuz]

Cadillackid:

Bigfoot 111 is helping me, and he really appreciates your help.

Fortunately! The charge he put in the other day is cooling! I need to check it again, since it has been a week.

I am not sure if it was “fixed with cans of dye and stop leak” or not. I suppose that will reveal itself at some point.

Unfortunately we have not really done anything to “fix” it, just charge it. , so my guess is that it is temporary.

Unless praying has worked, and I will not rule that out

 

[cadillackid]

Cadillackid:

Bigfoot 111 is helping me, and he really appreciates your help.

Fortunately! The charge he put in the other day is cooling! I need to check it again, since it has been a week.

I am not sure if it was “fixed with cans of dye and stop leak” or not. I suppose that will reveal itself at some point.

Unfortunately we have not really done anything to “fix” it, just charge it. , so my guess is that it is temporary.

Unless praying has worked, and I will not rule that out

fantastic that its cooling.. even if it leaks out you have ruled out, electricals, fans ,etc.. in fact while its cooling its a good ideas to check all of your outside fans and make sure they are in running order as well as good airflow from them..

 

[ChurchBuz]

in fact while its cooling its a good ideas to check all of your outside fans and make sure they are in running order as well as good airflow from them..

Do those outside fans always run, or do they cycle off and on? Just wondering in case I need to be patient to wait for them (that blow on the condenser) to come on.

 

[cadillackid]

Do those outside fans always run, or do they cycle off and on? Just wondering in case I need to be patient to wait for them (that blow on the condenser) to come on.

on my TRANS/AIR system the outside fans cycle with the compressor.. inside fans run any time the system switch is on.



on my ProAIR system the outside fans only shut off if the inside thermostat setting is reached.. if the compressor cycles out due to the freeze-stat or cold-discharge air sensor then the fans continue to run..



those outside fans should definitely be running anytime the compressor clutch engages.. although I suppose its possible they had a sensor to run those fans only when the head pressure is high enough but that would be a Rare system...



if the system loses its freon and triggers the low pressure switch, most will not run the outside fans (Trans /AIR wont even run the inside fans then)

 

[HamSkoolie]

Cadillac


In all your AC work have yo come across (even a ball park) for:


1) How many horsepower a big transair OEM system takes per compressor?


2) How many amps are required to power an EM1?


3) How many amps are required to power an EM3?


4) How many amps are required to power a CM3?


I'm asking because that's what I removed and I'm curious how much of my 160 amp alternator was there just to run those. I can't imagine the computers and other electrical loads remaining on the chassis can be even 100 amps and I'd like to tap a chunk of that alternator output for charging house batteries when we're mobile but I don't want to exceed 90% of design capacity for longevity purposes.