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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: viento1 on May 17, 2009, 01:11:05 PM

Title: Stand alone AC vs Rooftop
Post by: viento1 on May 17, 2009, 01:11:05 PM
Hey guys,

I was in Home Depot the other day and noticed a sale on a stand alone AC unit, looks really sharp, could easily find a place alone a wall for it and the discharge ventpipe can easily be directed into the bay and out the bottom. I have one rooftop AC and one split AC in the back. I really really hate the roof top unit in the front -

Besides going from 13k to 10k any other issues??

the price is $499 canadian


Title: Re: Stand alone AC vs Rooftop
Post by: Nick Badame Refrig/ACC on May 17, 2009, 02:23:27 PM
Hi Viento,

You will need two pipes, 1 for makeup to the condencer, and 1 for exhaust. If not you will pull conditioned air out of your coach.

Other then that, to each his own!

Good Luck
Nick-
Title: Re: Stand alone AC vs Rooftop
Post by: belfert on May 17, 2009, 02:31:29 PM
Reports are that the BTU ratings on those units are greatly exaggerated and a roof air with the same or lower rating will do better.

I think it was Jerry Liebler that reported installing a mini split and it performed even better than a roof air of similiar rating.  He reported that manufacturers of RV A/C units don't have to have them tested for BTU ratings so even roof airs may have exaggerated ratings.
Title: Re: Stand alone AC vs Rooftop
Post by: edroelle on May 17, 2009, 04:37:11 PM
Actually, a home unit will likely have higher REAL capacity than an RV unit, of the same BTU rating.   This is because of the test criteria being more stringent on the home unit.

Ed Roelle
Title: Re: Stand alone AC vs Rooftop
Post by: Jerry Liebler on May 17, 2009, 04:52:35 PM
DON"T waste your money on a portable air conditioner.  Portables are not under ANY form of specification control, the makers all claim far more capacity than the units deliver.  Since there is government supervision of household unit's specification and performance, they generally do what they claim.  RV units are to some extent kept honest by the RV makers but their numbers are inflated about equally for all brands.  The Rv units are tested with 80 degrees inside and outside temperature which is far less realistic than the 80 degrees inside and 95 outside used to test home units.  Because of the ratings issues a 12,000 BTU/h minisplit will always out cool a 15,000 BTU/h rooftop and use far less power doing it.
Regards
Jerry 4107 1120
Title: Re: Stand alone AC vs Rooftop
Post by: viento1 on May 19, 2009, 07:13:51 AM
Done!  the thought is stricken from my mind. Nothing more than a distant memory - Thanks for the reality check!

Anyone have a low profile Roof AC. I will throw in the old unit free of charge

Title: Re: Stand alone AC vs Rooftop
Post by: JohnEd on May 19, 2009, 11:32:52 AM
Jerry,

You again seem to have inside(pro) info/experience with mini-splits.  They interest me!  At least for RV/bus apps.  Have you located a condenser unit that is square, rather than round, that will take up less space in the bay and be easier to ventilate?  Make that has air handlers that are quiet?  Other points of interest?  How about durability in a bus application/

Thanks,

John
Title: Re: Stand alone AC vs Rooftop
Post by: Jerry Liebler on May 19, 2009, 03:01:48 PM
John,
     The extent of my research was to find a minisplit that I could fit into my bus.  I have it installed and it works very well.  It is an 18,000 BTU/h heat pump that'll cool my bus to 72 degrees while driving on a sunny 95 degree day.  The outdoor portion fits in what used to house the condenser of the OTR bus HVAC system.  The indoor portion is high on the wall directly behind the driver ( I wish I'd have put it on the curb side instead so the driver would be bathed in the coolest air).  My minisplit requires 240 volts which I obtain from a step up autotransformer so I only need 120 volts.  At max cooling my inverter is supplying 13 amps of 120 volt power.  For more details feel free to send me an email with your phone # and we'll discuss. 
Regards
Jerry 4107 1120
Title: Re: Stand alone AC vs Rooftop
Post by: Hartley on May 19, 2009, 04:57:58 PM
The portables are good for the workshop to blow cold air into the bays while
you are in there sweating and cussing at stuff that don't work.

We had a 5,000 btu unit on a cart with a long hose that fit into the pilots
window when working inside aircraft. Nothing like 90 degree weather and sitting
inside a plane on the tarmac trying to work on the instruments....

I had one rigged up and used it when I worked on the bus... Very nice...
Title: Re: Stand alone AC vs Rooftop
Post by: zimmysurprise on November 05, 2012, 01:25:53 PM
Anyone consider using the Coleman Park Pac unit designed for Park Models? Just looking for a way to use existing ductwork with 110v and keeping the roof sleek.
Title: Re: Stand alone AC vs Rooftop
Post by: belfert on November 06, 2012, 06:07:23 AM
Quote from: zimmysurprise on November 05, 2012, 01:25:53 PM
Anyone consider using the Coleman Park Pac unit designed for Park Models? Just looking for a way to use existing ductwork with 110v and keeping the roof sleek.

Coleman makes a version of this same unit for RVs.  Not sure if there is really any difference between the park and the RV model.  Ron the Bus NUt might still have some of the RV units.  (ronthebusnut.com)
Title: Re: Stand alone AC vs Rooftop
Post by: TomC on November 07, 2012, 03:20:14 PM
The Penguin 15,000btu is actually a 13,500btu with stronger fan motor to push the air through ducts.  It is one of the quieter roof A/C's with 3 spd motor instead of just a 2 spd.  I'm using two 15,000btu Penguins converted to basement and love the quietness of them.  Good Luck, TomC
Title: Re: Stand alone AC vs Rooftop
Post by: Oonrahnjay on November 08, 2012, 09:51:28 AM
Quote from: TomC on November 07, 2012, 03:20:14 PMThe Penguin 15,000btu is actually a 13,500btu with stronger fan motor to push the air through ducts.  It is one of the quieter roof A/C's with 3 spd motor instead of just a 2 spd.  I'm using two 15,000btu Penguins converted to basement and love the quietness of them.  Good Luck, TomC 

    That's good info, thanks Tom.  Looking at my available space (no rooftop, no bays), I'm beginning to think that my best combo is two mini-splits and one "conversion" as you've done.  Thanks for the photos you posted a few weeks ago, if there is more info and more photos, I'd like to know that.  Thanks,  Bruce H  NC  USA