Community Forums

GaryG · 10-12-2008, 12:49 PM

I was just informed by a repairman that I shouldn't drive long distances with the chasis (dashbaord) AC on. He told me the compressor is no larger than that in a auto, and it has to push through 80' of ductwork. He told me to only use it around town and for longer drives to use only the roof mounted AC's with the generator.
We have a 2007 Fleetwood Revolution with the Denso climate control. It has the Cat C9 400 HP engine. We are just not comfortable in the Florida heat with just the roof AC's.
The repariman claimed that the compressor is small and not made to run continually in an RV. If it seizes it will break a belt that could likely get cought up in the other engine belts and cause a serious breakdown.
Up until now we have been running it all the time we travel, which has been about 15K.
Any thoughts or info is greatly appreciated.

Gary and Norma
2007 Fleetwood Revolution 40E
2007 Honda CRV

GaryG · 10-12-2008, 12:49 PM

I was just informed by a repairman that I shouldn't drive long distances with the chasis (dashbaord) AC on. He told me the compressor is no larger than that in a auto, and it has to push through 80' of ductwork. He told me to only use it around town and for longer drives to use only the roof mounted AC's with the generator.
We have a 2007 Fleetwood Revolution with the Denso climate control. It has the Cat C9 400 HP engine. We are just not comfortable in the Florida heat with just the roof AC's.
The repariman claimed that the compressor is small and not made to run continually in an RV. If it seizes it will break a belt that could likely get cought up in the other engine belts and cause a serious breakdown.
Up until now we have been running it all the time we travel, which has been about 15K.
Any thoughts or info is greatly appreciated.

Gary and Norma
2007 Fleetwood Revolution 40E
2007 Honda CRV

GaryKD · 10-12-2008, 01:36 PM

For 30 years, I've been running the dash air when traveling. Roof A/C is on, only when needed. I've had only the usual maintenance/replacement of parts, from time to time.

Norm Payne · 10-12-2008, 03:24 PM

Gary, I think its time to find a new RV technician. Your dash air conditioner will last many miles and it is designed for your motorhome.

I once had a technician tell me not to use my 2000 watt inverter because to make a pot of coffee or for my wife to use her hair dryer. He said the inverter would cause electric problems and I should always run the generator when I needed 110-volts. I made a point to never use that technician again.

becks · 10-12-2008, 04:43 PM

Ditto...New technician time.

historyljc · 10-12-2008, 05:38 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Ditto...New technician time. </div></BLOCKQUOTE>
Run, don't walk!

chasfm11 · 10-12-2008, 07:36 PM

I'm amazed at the information that I've gotten from "experts". When we bought our RV, it was making a horrible thumping racket when I backed up and applied the brakes. I called the local Freightliner dealer to make an appointment to have the brakes looked at. He said "save your money, your problem is that the brakes haven't been used and what you are hearing is glazing on the brake shoes."

He was dead wrong. What I was hearing was chattering because of the slack adjusters not working properly. It takes a lot more brake pedal pressure than our RV had before we bought it to activate the slack adjusters. Since then I have a complete air brake system check out which also makes sure that the slack adjusters are working correctly.

In algebra "X" is the unknown quantity. In plumbing, a "spurt" is a drip under pressure. One can logically conclude that, sometimes, an "expert" is an unknown drip under pressure.

paz · 10-13-2008, 03:10 AM

It's true the dash air isn't that powerful, but it should be able run full-time for long periods with no problem. We almost never use the roof air when traveling except when it's extremely hot. Although the back of the motorhome may be warm, the dash air usually does an OK job of cooling the cockpit area. It may take a few extra minutes to cool off the coach when we arrive at our destination, but we figure there is no point in wasting gas running the generator to cool the back of the coach while traveling when no one is back there.

As far as having to push the cool air through 80' of ductwork, that is simply not true. The dash air comes out of the dash just like it does in a car. It does not get circulated through the coach ductwork.

Blue Ribbon · 10-14-2008, 08:14 AM

We run dash air 100%. May run front roof A/C until the MH is down to a "reasonable" temperature. If it is above 90 outside, generally the roof A/C (only 1 of 2 units) is on all the time also.

GaryG · 10-14-2008, 02:14 PM

Thanks for all the responces! It's great to have a place to sort out the information I'm given. This is our first motorhome and we're still experiencing a learning curve. It's good to know that we can continue to travel with our dash AC on.

georgetown350 · 10-14-2008, 08:10 PM

Dash air on an rv is no different then on a car. Use it or lose it.

Ask your repairman if the air goes through your duct work after it hits you in the face

Steve N Sal · 10-15-2008, 12:51 AM

I don't really agree with your Techs answer. I think it's more of a comfort tool. If the dash A/C keeps you comfy that's all that's needed. Myself in our previous unit I normally ran the roof A/C and had the two dash fans on circulating the air. That seemd to work better for us then just the dash air. Again this was only a personal prefference for us.

porscheracer · 10-15-2008, 01:10 AM

I'm still being flabbergasted by a "tech" who thought the dash air was ducted from the engine area. Sounds like one of the wash bay trainees escaped onto the shop floor and was "posing".

We run the dash air as primary, and use the genset and the coach air if the dash air can't keep up. In hard pulls, I'll turn the dash air off to get my ~5HP back, and help keep engine temps down.

We're also not of the "economy over everything" mindset. Comfort comes first, and if we use some fuel being comfortable, so be it.

GaryG · 10-15-2008, 03:20 AM

In defense of my tech, I think he meant that the compressor has to move the freon to the front of the coach and and back again. He didn't mean through the ductwork. This was my mistake. I guess the coil or evaporator is in the front. I wish I was more mechanically minded.
Anyway, it's good to hear that I should be OK running the dash AC. We are also very comfort oriented.
Thanks