AC - Is this cold enough

[gedlaw]

First time RV'r. Checked AC today and its putting out 47 degrees with ambient temp outside of mid 70's. Is this good enough or should I take it to a tech to check if its need to be charged? Planning trip across the desert this summer and want system to be at its best.
Thanks.

[MutinyGuy]

Originally Posted by gedlaw

First time RV'r. Checked AC today and its putting out 47 degrees with ambient temp outside of mid 70's. Is this good enough or should I take it to a tech to check if its need to be charged? Planning trip across the desert this summer and want system to be at its best.
Thanks.

You should have a split of ~20 degrees between input and output of the AC unit...so if you are measuring 47 degrees on the output of the AC then you should see a split of close to 20 degree on the input....so ~ 67 degrees on the input side of the AC...what are you measuring?

[Old Scout]

The question is not ambient outside temps but ambient inside temps. General rule is that your evaporator coil can output a max temp differential of 20-25 degrees. So if inside coach temp [ ie, measured at floor level] is 70 degrees, then 50 to 45 degrees out the vent is pretty good. As inside ambient temps drop, then air temps at the vent will drop too, thus allowing the coach to cool down further. Accordingly, if traveling in hot conditions, put dash selector on recirc. so you don't keep trying to cool air from the outside.....
Having said that, RVs are huge heat sinks so the dash A/Cs and perhaps even the residential [roof A/C] wont keep up with desert heat, in full sun.....

[HR2004]

Be advised. They are not designed to be recharged. There are no ports.

[xrated]

Actually, an 18 to 20 degree difference between the inlet temperature and the outlet temperature is pretty good for a correctly sized unit.

[gedlaw]

You guys are great. I get it now on ambient versus coach temp. I had heard about the twenty degree differential but didn't quite get it. This is a great site. Appreciate your help and explanations.

[Davidrvr]

Originally Posted by HR2004

Be advised. They are not designed to be recharged. There are no ports.

But they can be added and recharged.. Have had the it done on the last 2 coaches

[mrt_1111]

Originally Posted by Davidrvr

But they can be added and recharged.. Have had the it done on the last 2 coaches

For future reference, please tell...

[MutinyGuy]

The only reason to add a port is if there is a leak or the compressor, expansion valve etc is defective and you have to open up the system to replace the defective part. Once you do that the only way to add freon back into the system would be through a port which should be brazed in. Stay away from the piercing ports as they have been known to leak.

[Hittntheroad]

Hiring an ac mechanic at 100 an hour plus parts, it's better to just replace these disposable units. Especially if the unit has any age on it. Newer units are more efficient. Our local dealer has literally hundreds of them in a pile in the back of his lot.

[spyderRV]

Originally Posted by Hittntheroad

Hiring an ac mechanic at 100 an hour plus parts, it's better to just replace these disposable units. Especially if the unit has any age on it. Newer units are more efficient. Our local dealer has literally hundreds of them in a pile in the back of his lot.

I added ports to mine because I also added a TXV to replace the capillary tube. Made it a bit more efficient and less likely to freeze and totally cost prohibitive if I had to pay anybody to do it.

[bruceisla]

Originally Posted by spyderRV

I added ports to mine because I also added a TXV to replace the capillary tube. Made it a bit more efficient and less likely to freeze and totally cost prohibitive if I had to pay anybody to do it.

And at today's prices for R-22 (older units) it's mostly a non-starter.

[spyderRV]

Originally Posted by bruceisla

And at today's prices for R-22 (older units) it's mostly a non-starter.

Yep, last #30 bottle I bought was close to $300. Reclaimed and reused!

[JFN]

R22 is close to $1600.00 a bottle now.