Automotive Air Conditioning Information Forum

I have a 2013 Thor, Daybreak motor home. It's on a ford f53 chassis, with v10, I replaced the ac condenser, it was leaking at lower corner. I never lost all the refrigerant, system was cooling good. I added 3 oz of oil, directly into condenser. I vacuumed for an hour. Added 4 12oz cans r134, pressures are 20 low, and 170 high, ambient temp 75, It seems to cool OK, I can see bubbles in sight glass. Does someone know how much refrigerant this system holds?

On the old forum, I had a PDF of listings. Can't find it now.

Check that the top and bottom tubes on the evap are about the temp.

I think the upper one was colder, but not a lot. The motor home is at a storage lot, so I can't just run out there and check. My question is, do I still ned to add more Freon to get the pressures up to normal?

ggoguen wrote:Added 4 12oz cans r134, pressures are 20 low, and 170 high, ambient temp 75, It seems to cool OK, I can see bubbles in sight glass. Does someone know how much refrigerant this system holds?

ggoguen wrote:I think the upper one was colder, but not a lot. The motor home is at a storage lot, so I can't just run out there and check. My question is, do I still need to add more Freon to get the pressures up to normal?

Yes, you still need to add more R134a - don't add any sealers or R134a containing sealers !!!!

If your ambient temperatures are over 80F at this time of year, then typical high side pressures (measure pressures at like 1500 to 2000 rpm) would be somewhere like 230-270 psi. You do NOT obtain full 12 oz. from a can either, and hopefully you're purging the service gauge hoses of air using a small amount of R134a in the process of filling. So add a half-can, or a full can, and measure the pressures, don't rush the process. Repeat if necessary.

Obviously the best way is to have a machine that adds exactly the correct amount automatically like a shop would have, but one would need to know the real capacity.