Rooftop Air How Many?

[scanzel]

I decided to go with rooftop air units on my conversion, I will retain most of the original glass. What is the general opinion as too how many units are needed. I will be using the Carrier low profile 15,000 units. I figured 3 should cover it nicely at 74 to 78 degrees inside temp, we do not like it too cold.

[gus]

This is a pretty impossible question to answer because so many things enter into it.

You need to be a lot more specific about your conditions.

My one recommendation at this point is to put the front one as close to the driver as possible and rig it so it blows straight down to the aisle. There is no way you can get too much AC to the front because of the glass on three sides of the driver.

[Nick Badame Refrig/ACC]

Hi Steve,

Like Gus said, Lots of factors to concider.

3 is safe... you can always turn one or two off. but, you can't turn them on if you don't have them.

Good Luck
Nick-

[HB of CJ]

Three (3) is a really...cool idea.  Here is why.  By putting the first one (from the front) as close as you can to the driver's area puts cold air....on the driver.  Pretty necessary heading into the hot, setting sun driving West into the sunset during August at sunset in Texas or Bakersfield CA.

Mounting number two (2) slightly aft overtop the forward lounge puts more cold air on the passengers/pets that are riding in the forward lounge.  Also works blowing cold air onto the galley area when cooking hot food parked or underway.  Both one (1) and two (2) together work twice as good.

Putting the third (3rd) way back overtop the rear master bedroom puts a dedicated A/C where it is needed at night while again in Texas or Bakersfield during hot nights again in August.  And...the neat thing about mounting three (3) A/C units is that you have a choice of running only the two (2) you...

...need depending upon your particular conditions/requirements at the time in question.  Finally, by having three (3) but only running two (2) it may help balance the gen set in that one A/C runs off of each leg of the gen, thus maybe balancing the load if that is necessary.  Wow.  Make any sense?

[TomC]

I have a 40ft transit with BIG windows and three 13,500btu Colemans.  I removed the unnecessary windows, installed single pane Penninsula glass with a light gray tint, and insulated with 2.25" of blown in insulation.  Last weekend went through 107 degree weather and used just the two front ones.  Mine are positioned- the front one is just back enough and off set to the right (didn't want to cut the center roof beam) so it can blow right on the driver (me); the second is off set to the left in the center; the third offset to the left over the bed in the rear.  I by far use the center one the most especially when parked; use the front and center when driving; use the rear one sometimes when driving instead of the center, or when doing activities in bed.  But the rear on is too noisy to run overhead, so I use the center A/C when parked then open my bathroom door that has a 4 inch gap at the ceiling.  Cuts out most of the noise from the A/C but lets the cool air to come back.  Also, the quietest would be to duct them.  Good Luck, TomC