Running roof air

Mr.Mark wrote:

kirkifer wrote:
Thanks!

I can't argue with that explanation. For the cost of a Prevost, I would hope it worked that well!

Prevost's can be configured however you will use them. Personally, we have four roof airs that can run off of the four engine alternators as we have four 3,500 watt pure sine wave inverters.

Some coaches can be equipped with 'cruise airs' that are a basement unit. It is separate than 'over-the-road-air' that is run off of the main engine only. One of the show coaches that we looked at had two roof airs and two cruise air units, no OTR air. Some coaches can have four cruise airs and no roof air units. Like I said, you can customize how you will use the coach for your lifestyle.

Our dash air has two features, dash air and auxiliary air which is a secondary air behind the driver's and passenger seats. It works quite well to keep the front and passenger cool on hot days. The main dash air vents are at both front windshields with regular dash vents for the passengers (80% of the air comes out of the windshield vents). The auxiliary air behind the seats balances that dash air design.

Now, if I run the roof airs from the inverters, all is well but I'm not really recharging the Lithium Ion phosphate batteries that are also running the two refrigerators or any other item that is on in the coach.

So, when we arrive at a campground, the first thing that happens once I plug into a 50 amp outlet is that the battery charger goes into HIGH charge. It's pulling major amps! I really can't use all of the airs right away until the batteries level off. Just something to keep in mind.

If I run the generator, maybe, the last hour before landing, everything is charged and the coach is cool from running the roof airs. That way, I have complete use of anything in the coach without worrying about the batteries charging in high mode.

Prevost coaches that have more than two slides cannot have 'over-the-road-air'. The duct work at the windows cannot be installed in a slide, hence, two slides max with OTR air.

Safe travels,
MM.

Not sure I followed all that. Perhaps we should arrange a test drive for me so I can see it first hand. ;)

kirkifer wrote:

Roadpilot wrote:


We run dash air and 1 or 2 roof air's off the alternator - no generator.

Okay. Please explain this? I really do not care where the cool/heat comes from. I like that there is only one engine running at a time. I have concerns about constantly running the generator, unless that really should not be a concern.

I assume the alternator is aftermarket and very robust? It charges the batteries and the batteries and inverter power a couple of the roof units?

The "alternator" he is talking abut is likely an 8000 watt version which is mounted to the engine and works much like a generator would as it provides plenty of power to run 1 or 2 inverters allowing the use of roof airs going down the road. They eat fuel as well as it can take as much as 50 HP from the engine to operate this beast.
To your comment about running your generator, you really should not be concerned. It will work fine and there are no issues with running while driving or parked other than it burns some additional fuel. If your dash air is working properly you should be able to keep the drivers cab area cool unless you are in very hot weather. When you get where you are going your coach air will cool the rest of the coach pretty rapidly. In most cases, there is no reason to keep the entire coach cool while driving.

Even some of the older Bluebird's (LX and LXI's) have the ability to run roof airs off the alternators...many have 24 volt systems/300+ amp alternators. I like the idea of having 4 3500 watt inverters...wow, maybe when I hit the lottery I can get me one of those coaches. Oh wait, I guess I have to play the lottery to win..LOL

I don't have roof air (I have basement air) but I've owned RV's in the past with roof air and, I have run the genset before while driving to power the roof air. My dash air doesn't cool enough in very hot weather, especially in the Southwest.

kirkifer wrote:
Thanks!

I can't argue with that explanation. For the cost of a Prevost, I would hope it worked that well!

Prevost's can be configured however you will use them. Personally, we have four roof airs that can run off of the four engine alternators as we have four 3,500 watt pure sine wave inverters.

Some coaches can be equipped with 'cruise airs' that are a basement unit. It is separate than 'over-the-road-air' that is run off of the main engine only. One of the show coaches that we looked at had two roof airs and two cruise air units, no OTR air. Some coaches can have four cruise airs and no roof air units. Like I said, you can customize how you will use the coach for your lifestyle.

Our dash air has two features, dash air and auxiliary air which is a secondary air behind the driver's and passenger seats. It works quite well to keep the front and passenger cool on hot days. The main dash air vents are at both front windshields with regular dash vents for the passengers (80% of the air comes out of the windshield vents). The auxiliary air behind the seats balances that dash air design.

Now, if I run the roof airs from the inverters, all is well but I'm not really recharging the Lithium Ion phosphate batteries that are also running the two refrigerators or any other item that is on in the coach.

So, when we arrive at a campground, the first thing that happens once I plug into a 50 amp outlet is that the battery charger goes into HIGH charge. It's pulling major amps! I really can't use all of the airs right away until the batteries level off. Just something to keep in mind.

If I run the generator, maybe, the last hour before landing, everything is charged and the coach is cool from running the roof airs. That way, I have complete use of anything in the coach without worrying about the batteries charging in high mode.

Prevost coaches that have more than two slides cannot have 'over-the-road-air'. The duct work at the windows cannot be installed in a slide, hence, two slides max with OTR air.

Safe travels,
MM.

the dash air on our 2004 Class A went out and they can't find the problem. also in hot temperatures over 85-90 degrees the dash AC won't cool enough due to the open space. We just run the generator and the front roof AC.

Keep in mind the Over the Road (OTR) AC is also used to defog the windshield when you set the HVAC to Defrost. When you are on the road in the winter it will be easier to see if the Defrost function as the AC operating to dehumidify the air blowing on the windshield.

We run the dash ac and we also have over the road air.

As we go down the road, we hang a shower curtain behind the driver's seat and the co-piolt and it keeps that area warm/cool. simple fix

Thanks!

I can't argue with that explanation. For the cost of a Prevost, I would hope it worked that well!