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sandz
03-11-2020, 10:01 PM
Anyone know what the charge is on the a/c on an old xl? This is a 1985 with r12. York compressor running off the camshaft pully.
Compressor says 10 oz oil charge and I am guessing about 4 oz for the rest of the system.
I am also guessing 4 to 5 lbs of r12 but if anyone happens to know for sure it would help.
Only the one evaporator in the dash.

Gil_J
03-12-2020, 08:22 AM
If the service manual is not available on line, I'd call Prevost PASS. I believe the newer dash only systems are charged to about 7 pounds.

BGLogistics
03-12-2020, 09:37 AM
Thread derail - Sandz I remember when you guys initially posted pics of this bus. Your interior/woodwork is the most beautiful of any coach I've seen yet. Ever.

sandz
03-12-2020, 10:03 AM
Thanks Billy! We love the interior. Makes all the work we have done on the bus worth the effort when we kick back at end of day

Gil I will try calling PASS. I have noticed there is more documentation for this bus coming online at Prevost.
Wiring diagrams mostly. Hopefully they are working on scanning more docs for the older busses.

sandz
03-14-2020, 01:40 AM
I did call PASS. they promised to get back to me in a week or so.

Meanwhile I went ahead and charged with the equivalent
of 4 bs of r12 and it is cooling really well.

I will probably catch flac for this but I use a hydrocarbon refrigerant. Envirocool.
I charged the system with 25 oz of envirocool (r290/r600 i think) basically a propane/butane mix. I used to mix it myself using coleman propane and ronson butane. This was many years ago before the envirocool was available.

5 oz envirocool is equivalent to 13.3 oz r12

Anyone with an old r12 system that needs a better refrigerant could check this out.
Anyway it works good in the old bus.

solarchild1
04-21-2020, 10:59 PM
Nice to see u using that refrigerant.most of the rest of the world new about it 50 years ago.all of my vehicles had it installed .no problems or failures in 25 years.my over the road ac and. Coach airs work great 5 to degrees cooler than 134a.never converted most of them.