June 23, 2018, 06:43:02 AM

Author Topic: How many roof AC units do I need?  (Read 4359 times)

Offline 86neoplan

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How many roof AC units do I need?
« on: May 31, 2006, 11:19:55 PM »
as most of you know, My little coach is only 26 foot long, and thats bumper to bumper...

I am trying to figure out how many roof airs I need.

Any suggestions?


shawn
Proud single custodial dad to a wonderful 14 year old son, Owner of a 1986 Neoplan 26' transit Bus AN408, Great weekender...Lots of work to come on this bus, can't wait to get her done! 8.2L with a Allison AT545...

Offline coachcrazy

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Re: How many roof AC units do I need?
« Reply #1 on: May 31, 2006, 11:25:52 PM »
last year i rented a 28ft class C and it had one 15,000 btu  roof unit and that made the bus plenty cold.

Offline Ross

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Re: How many roof AC units do I need?
« Reply #2 on: May 31, 2006, 11:44:19 PM »
I went with 3 roof units...15K each.  Basement was quite a bit more money and I didn't want to raise the roof.  If you go basement, you should plan on a roof raise to accomodate duct work.  This being my first, I wanted to keep it simple....and it still took 3 years to build. :)

Dallas

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Re: How many roof AC units do I need?
« Reply #3 on: June 01, 2006, 12:20:31 AM »
Cat and I saw a 45' Dutch Star last fall that had 6 roof airs on it.
Let's see, 45 divided by 6 = 7.5' per A/C
So using that we can surmise that 26 divided by 7.5 =3.4666666666666666666666666666667 A/C's.
So now we can round it up, since obviously the Dutch Star, being more expensive has better insulation  :-\
We'll call it 4 roof airs.
That should allow you to keep the temperature about 34° in Death Valley in July.
It'll also help keep the beer a lot cooler so you don't have to work the fridge so hard.
Of course, you'l probably need 2 12.5 KW diesel gensets, but Hey, who's counting! ;D ;D ;D

Dallas

Offline TomC

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Re: How many roof AC units do I need?
« Reply #4 on: June 01, 2006, 05:18:06 AM »
Depending on if you're going to have an engine run dash air.  If so, one roof air would be enough.  If you don't have the dash air, then one in the middle and one near the front.  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline FloridaCliff

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Re: How many roof AC units do I need?
« Reply #5 on: June 01, 2006, 12:05:11 PM »
Depends!

If you are keeping all the glass you will probably want two to be safe.

There is a ton of cooling/heat loss when moving.

If on the other hand you are covering the bulk of the windows I would go with one 15K.

A 13.5 would freeze me out in my 27' Class C when not moving, but just not enough when moving, the 15K may do the trick if near the front.

Remember that the driver is in the discomfort zone with all that glass and hot/cold air on the front when your moving.

Best of Luck,

Cliff
1975 GMC  P8M4905A-1160    North Central Florida

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Offline Danny

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Re: How many roof AC units do I need?
« Reply #6 on: June 02, 2006, 01:33:09 AM »
As everything else, it would depend on what your plans are for the bus.  I do not like hot weather - so, I want to travel in temps that are more reasonable.  Considering this might help you make the call...

Danny
I have heard it said, "life comes at you fast".  I didn't know it would be in the shape of a bus  :-)

Offline plyonsMC9

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Re: How many roof AC units do I need?
« Reply #7 on: June 02, 2006, 02:54:36 AM »
Hi there '86,

I had a class A, 34 foot.  Two roof airs.  Insulation was pretty good.  White roof.

We about had heat stroke in Blyth CA, when the temps passed 120 degrees.  Had both roof airs and the in-dash A/C going as well. 

Ever since then, I've been a big fan of more rather than less A/C units.  On our 40' bus, we have 3.  And I've never regretted having more a/c units.  If you aren't using it, then turn it off.   ;D  If you need it, it's there.

OK, that's my 2 cents.

Hope this helps - good luck with your decision.

Kind Regards, Phil
Northern Arizona / 1983 - MC9

Offline tucsontattoo

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Re: How many roof AC units do I need?
« Reply #8 on: June 02, 2006, 03:55:07 AM »
  Four!


                                 Tucson
we do things three ways,good,fast or cheap. PICK TWO!

Offline Danny

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Re: How many roof AC units do I need?
« Reply #9 on: June 02, 2006, 04:23:04 AM »
I guess another way to put it is:

Depends on how hot is it outside and
How cold you want to be inside   ;)

Danny
I have heard it said, "life comes at you fast".  I didn't know it would be in the shape of a bus  :-)

Offline Len Silva

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Re: How many roof AC units do I need?
« Reply #10 on: June 05, 2006, 02:07:02 AM »
I'm just going to set the GPS for 72 degrees and not worry about the air conditioners ;D

Len

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Dallas

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Re: How many roof AC units do I need?
« Reply #11 on: June 05, 2006, 02:28:23 AM »
I'm just going to set the GPS for 72 degrees and not worry about the air conditioners ;D

Len

Len,
Is that 72° altitude or rectitude?

Dallas