Air Conditioners Won't Keep Up

[melcain]

We have a 2008 36-foot Phaeton with four slides. We have trouble with the air conditioner keeping it cool while we are traveling down the road. Does anyone else have this problem? While parked and all slides are out, it gets cool and stays cool.

[hermanmullins]

Let me be the first to "Welcome you to the Forum." We have found that when we are moving down the highway in hot weather, we put up a curtain we made. It goes across the coach just behind the driver and passenger's seat. It will keep us very comfortable with the dash air. If, however, you have guest along for the ride, you will need the roof air. If you can run the roof air to cool down the coach before you begin to travel, then it should maintain the cooler temp. We, when just the two of us, will also turn on the gen set about 30 minutes before we are going to stop for the night to help begin the cool down. Good Luck and Keep your Cool.

[Guest BillAdams]

We have a 2008 36-foot Phaeton with four slides. We have trouble with the air conditioner keeping it cool while we are traveling down the road. Does anyone else have this problem? While parked and all slides are out, it gets cool and stays cool.

Are you just using the dash air to keep cool or are you running the generator and the roof airs while traveling?

[tbutler]

If you are using your roof air conditioners and still not getting the cooling you desire, you might check the ceiling vents. Our coach has vents which can be rotated in different directions. When we are parked, the roof vents are turned to direct cooling air toward the couch, recliner, etc. which are in the slides. When we bring in the slides to travel, those vents are now pointing at the top of the slide. With four slides, you could have all your ceiling vents aimed at the top of the slide which makes it very difficult to circulate the cool air that you desire. When we travel, I aim the vents toward the center line of the coach and the front ones are all pointed forward toward the driver's and passengers seats.

While the rear air conditioner doesn't supply cool air directly to the front of the coach, we'll still run it as it does help to reduce the overall temperature in the coach. Both our AC's feed air to the vent system in the roof. If both are running it increases the amount of cool air that comes from each vent. Having cooler temperatures throughout the coach means that the warm air returning to the AC unit will be cooler which makes the output air from the AC a little cooler. For this reason, we run both AC's and we don't close any vents, just aim them into the active portion of the coach as we drive.

[kingfr]

Run the generator and the roof airs! We have the generator autostart set so that when the front A/C unit wants to start the genny starts and we get cool. We keep the thermostats set on 75 degrees. Both a/c's run in really hot weather, but we are able to stay cool even in the hot southwest in summer. Do be sure that your electric hot water heater switch is off, or you can cause the genny's breaker to pop if both a/c units AND the hot water heater try to run.

[Guest Wayne77590]

Have you measured the temperature coming out of the dash vents? I have a refrigeration thermometer - stem type - that I stick in a vent and I can monitor it. I have found in really hot weather that the dash air is not sufficient to cool the entire coach. When I see the temperature rising on the thermometer I turn on the house AC, and keep the dash in MAX AC, as this will recirculate the house air and assist in the dash air cooling down. JMHO

Good luck.

[bartman62]

we have a 430qs charleston by forest river that cannot keep the coach cool with both 15,000 btu units running on high when the weather is between 80. and 95. f any thoughts would be appreciated.

[Guest BillAdams]

Wow! Maybe you should try closing the doors and windows!!

Are you getting good air flow through all of the vents? Do you have the option to open a grill directly under the A/C and blast all the air directly by-passing the vents? Have you removed and cleaned the filters? Is the air that is blowing cold? Are the compressors (not just the fans) running and never cutting out? Is there hot air blowing from the A/C up on the roof? Anything else you have checked?

[bartman62]

Wow! Maybe you should try closing the doors and windows!!

Are you getting good air flow through all of the vents? Do you have the option to open a grill directly under the A/C and blast all the air directly by-passing the vents? Have you removed and cleaned the filters? Is the air that is blowing cold? Are the compressors (not just the fans) running and never cutting out? Is there hot air blowing from the A/C up on the roof? Anything else you have checked?

Thanks for the humor Bill, but seriously these are (2) 15000 btu dometic duo-therms, I have checked everything you mentioned. Is there something wrong with my coach or do I need to add another roof-top?

[shields]

With a 36' coach and both 15Kbtu a/c units running, plus the dash air, you ought to be cool unless the ambient temperature is well over 100 or the humidity is awful. We travel through the desert near Las Vegas each July and have similar problems when its really hot. Here's what we've tried:

1. Make sure the dash a/c is set to max. That way it draws cool air from the coach and cools it further, instead of taking in hot air from outside.

2. Make sure bath or kitchen vents are closed.

3. Window shades down.

4. Point rooftop a/c vents straight down into the coach, so they don't output cool air along the warm ceiling.

5. Park in shade at all stops if possible.

Are you sure the a/c units are all working properly? If so, hopefully these will resolve things.

BTW: What are the outside temperatures and humidity when you have these problems?

Tim

[hermanmullins]

You stated in your first post that your coach cooled down when connected to 110 volts. Does it cool down faster when plugged in when you have shade then when no shade?

Here is just a thought. If your coach is cool from the evening and you know the day is going to be a schorcher, After unplugging start your gen and turn on the a/c to maintain what you have. If you are already traveling and decide that it is too hot so you turn on the gen. and a/cs you are already too late.

When going down the hwy. keep your coach as dark as possible. Close all blinds. Close off the back of the coach and only use the front a/c and dash air. Check you filters. Try putting one or two fans around to keep the air moving Was your coach made in the south or north? We had an Ultrastar made in the far north and our small a/c would cool it very well. (installation)

And last but not least, if none of our thoughts help, go north in the summer and south in the winter.

Good Luck and Keep your Cool.

[bizsmith@yahoo.com]

We too use a curtain behind the pilot/copilot seats. The dash air keeps that area cool plus the dash heater keeps the area warm in cold weather.

[desertdeals69]

If it's harder to keep cool when traveling than sitting still, check to see if there are air leaks under the dash from the outside.