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

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.

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

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.

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...

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,LarryDon'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.

Dash a/c not cool enough... | Good Sam Community

DSDP_Don
Explorer
Mar 22, 2015
Larry....When we traveled in the summer months in our Diplomat, I was not a big fan of running the generator and roof A/C all day. We use to use a spring loaded shower rod and a clear shower curtain that we put up right behind the front seats. You could still see in the back and the split in the curtain allowed easy access. Obviously, it's not a good idea if you have pets or people riding in the back.

It kept the front cool until about 3:00 pm and then we would turn on the roof A/C because we were usually ready to stop for the evening.
KilroyGuy
Explorer
Mar 21, 2015
It also helps to cool the smallest space available --- try closing the bedroom and/or bathroom door.
gsander1
Explorer
Mar 21, 2015
mike brez wrote:
Our dash and over the road air cool the whole coach fairly well.

That's because you have a Magna my friend.

One of the main benefits to owning the Country Coach Magna or Affinity is that the chassis A/C system has two evaporators. Dash evaporator is as much as 19K BTU depending on year. And bedroom evaporator is 13.5K BTU. I have yet to run generator and roof A/C on my coach and I live in hot, humid Birmingham, Alabama.
Golden_HVAC
Explorer
Mar 21, 2015
If you think about it, the dash air will cool off a 6 foot wide and 6 foot deep cab area of the F-150 really well. But the cab of the DP is 8'6" wide, larger glass area, and upwards of 30' long! So running the generator on a warm day is somewhat a requirement, as the dash air can only do so much.

Good luck!

Fred.
Mr_Mark1
Explorer
Mar 21, 2015
We had the air in our '08 Dynasty start blowing warm several times during the early years of ownership. After three attempts at Colton Truck Terminal in Colton, CA, the fixes didn't last long (waste of money). They just didn't know what they were doing and throwing parts at it.

So, I was so lucky to find Redlands Performance and RV repair in Redlands, CA. They fixed it right the first time. It ran cold for a solid three years until we sold it on consignment last fall.

We could run just the dash air until the outside temp was about 95 (for a couple of hours) then I would turn on the roof airs. Any outside temps at 90 or below, we were good with the dash air.

I never measured the temp out of the vents but when I put my hand up to the vent, the air felt ice cold coming out. The vast area at the front of a motorhome does make a difference but the air coming out of the vents should feel very cold.

Good luck,
MM.
Cobra21
Explorer
Mar 21, 2015
The dash air is to be about 20 degrees cooler the the ambient temp. inside.
So if it is 90 in the coach, then it should blow about 70. It will work its
way down as the inside temp keeps falling. Same goes for the roof top unit.
When it is 70 inside, the unit should blow around 50. When they run like this they are also pulling the humidity out which is the big thing!

Hope this helps, Brian

P.S. Some units just will not cool well depending on the sun, glass, insulation, and air leaks or quality of the build.
lj2654
Explorer
Mar 21, 2015
I had my dash A/C repaired 2 years ago due to a leaking line. Air was a lot cooler after the repair. 6 months later not as cold.

I decided it was wasting my money, so now I use the dash air early in the am, then run the generator and roof a/c's late morning and afternoon.
mike_brez
Explorer
Mar 20, 2015
Our dash and over the road air cool the whole coach fairly well.
wa8yxm
Explorer III
Mar 20, 2015
The Dash Air is designed for the cabin of a truck, Say an F-350 Ford

No way can it properly cool an entire

Two choices

1: There are companies that make an insulating curtain that goes just behind the front seats segregating the cockpit from the rest of the house.

Two... Help it along a bit by firing up ye-old Generator and activating ROOF AIR.
dougrainer
Nomad
Mar 20, 2015
midnightsadie wrote:
stick a temp gauge in the vent ,should read 42deg if its much from that its not right.

WRONG. This may be true for Automotive and Pick Up trucks, but is NOT even close for a Class A Motorhome. The FACTORY specs for a Class A Motorhome is 60 degree output at the nearest vent to the evap core with ambient temp above 70 degrees. . That said, most Class A's will get below 60 and even down to 48 to 50 degrees in sub 95 temps. Below are the 2 links for the BEST diag of Motorhome Dash AC systems. Doug

http://www.evanstempcon.com/tsg_opcheck.php

http://www.evanstempcon.com/tsg_guidelines.php

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