Dash a/c not cool enough...

...and I'll be sure to check that heater valve...thnx again!

Larry

Two class A motor homes and both had issues with the heater valve. That's where I'd start.

Once the engine is warm checking the outlet air temp is not going to tell you much as the heater may have hot water going through it. Checking the temp in the first couple minutes will. If the heater hoses in the dash are only warm it will be defeating the AC. Putting a manual shutoff valve in a line is the easiest solution if the electric motor is not shutting the water flow completely.
I rarely have to run the generator and roof ACs BUT I have a shutoff valve and I bypassed the defrosting relay so my compressor runs all the time. Taking the plug off of it and putting a fues in the plug is all it takes. In the East when the air flow decreases I shut the AC off for five minutes to let it melt the ice. Out West I rarely have to as the lower humidity takes longer to ice up.

I was referring to the air outlet temp. I'll check the temp there.

Thnx all the the good advice!

Larry

stick a temp gauge in the vent ,should read 42deg if its much from that its not right.

DoubleVeteran wrote:
Hi all,

I have a 2002 Phaeton DP, and the dash air has never been cold...only mildly cool. I know that is subjective, but for a comparison, the a/c in my 2009 Ford F-150 runs twice as cool as the Phaeton under the same conditions; highway speeds @ 85 degrees.

I had it checked at two different RV service centers and both said the air was working properly. I know I can run the genny and roof-top a/c, but I'm thinking the dash a/c should work much better. Is this typical of DP coaches to have marginal dash a/c cooling?

Thnx,
Larry

Don't know if you're talking air outlet temp. or cooling the interior, but the former should be near the same. With the latter, no way can you expect much from it and some have went so far, as to hang a curtain behind the front seats. I don't bother with it myself and consider them worthless.

My 2009 on normal AC is cool but once temp goes into the 80's I use MAX ac and the air is MUCH cooler due to it using recirc already cold air and not the air from right outside front which most likely is running the generator..Try the MAX AC setting, you might be pleasantly surprised...

The only way to tell if it is doing as it is suppose to, is check the temp of the air as it comes out of the dash vents. Compare to your other vehicles. There is a chart that tells what the temp coming out should be at a given outside temp. The MH has a much larger area to cool. Many of them do not work that well.

You may want to check the heater and make sure that valve is shutting off the hot water flow through the heater core. Some have found that both the in and out lines were hot, meaning that the air conditioner is also cooling the hot water from the heater core. This situation can be helped by putting an on/off ball valve in one line at the heater core and it shuts off all hot water flow through the heater core. Just one thing to check, Hope this may help. Happy trails Bert

I only have experience with my coach, a 1999 holiday rambler endeavor. Mine has the 5.9 24 valve cummins. I picked up the coach in august of 2014 and the air has always worked. It does blow cold and fairly hard, but I don't think you'll ever be satisfied if you're comparing it to a newer pickup truck.

The truck has a lot less room to cool, the DP has such a vast area to cool that you'll need to run the genny and roof airs to keep it cool in there if it gets up to 80 or 90 degrees. I had another gas coach with the 454 that I was dead set on getting it working properly.

I spent about $300 on new hoses, evaporator, condensor, etc. and got it charged. It did blow cold, and was a little helpful but still had to run the genny and roof air to keep it reasonable in there. Hope this helps.