Adding Roof Air Conditioner!

After 6 years of living with inadequate and unacceptable cooling from the basement air conditioner in our 2006 Voyage, I have an appointment with a local Dealer to install a Dometic Brisk Air High Efficiency 13,500 BTU roof air in place of the Fantastic Vent on the center of our unit's roof.  I'm sick and tired of burning up in our unit, and worrying about running both compressors when the outside humidity is in the low teens or single digits, as the inside coils freeze up due to low air flow when both compressors are running. 

I will be running my roof air almost extensively while driving, and also while parked, with supplemental flow from my basement air in the ducted ceiling.  ;D

This week I will be running a 12/2 with ground from the vent opening through the duct in the ceiling, back to the One Place area, and down to the breaker box, and will be using an "unused" 20 amp washer/dryer breaker as we removed the washer/dryer when we bought this unit.  The dealer will only be removing the roof vent cover, removing the Fantastic vent (hope he can get that darn Eternabond off!), and then installing the unit on the roof and installing the inside louver unit using the wiring I will provide.

When I asked the Service Manager if they have experience installing roof airs on Winnebagos, he replied "yes, quite a few have done this", and "yes, we have actual roof air installation on many Winnebagos, as there has been cooling complaints from owners of larger Winnies with multiple slides"  Nothing I haven't heard before!!!! 

Many thanks to John Canfield for his detailed and step by step installation with pictures on his website, and his many comments of "I should have done this sooner".  ;D

Also thanks to AZLoafer for his questions and consequent roof air installation.

Yea!  Congratulations Mark!

Adding a roof air was a significant improvement to our coach.  You will have the very best of both worlds - we love the basement air - it's quiet and does a good job unless you are in a very hot climate and it will remain our primary HVAC unit.  The roof air provides a wonderful 'turbo' mode for cooling and it is the first choice to use when on the road due to it being on the roof and away from dust and dirt of the road.

The added BTU of the roof air makes a great coach even better  .

I guess I'm lost on this, the only problem we ever had was when we left the coach out side for 2day's, and then tried to get it to cool down mid way thru the second day, other wise as long as you don't let the heat get ahead of you there was no problem, kinda like my house unit, I can't expect it to cool the house down from 100 to 76 in a matter of minutes.

am I the only one with out a basement air complaint?

plus what does that do to you over all height clearance? I can't afford to go any higher.

There are some with basement air that report being able to cool their coach down to 75 degrees in full sun with an outside air temp of 95 degrees.  That is not my experience and not the experience of many others.  If it works for you, that's all that matters.

The roof air is only 12" high or so if I remember correctly and adds no inches to my clearance (we have a King Dome, Datastorm Internet dish, etc.)

Update:  I decided to buy a 20 amp breaker (ordered on-line) and leave the washer/dryer breaker in place and unused as I like to plug in a 1500 watt heater in that dedicated line when we are in Breckenridge or other below 0 places in the Winter.

I am presuming I can run ONE of the compressors in the basement air AND the roof air at the same time with my 5500 Onan.  Does anyone know how to split up the amps on the generator, as there are two generator breakers, a 30 amp and a 20 amp.  I don't know what house appliances are on the 30 vs the 20 amp breakers on the Generator.  The new roof air will only use 10.8 amps as it's a new energy effecient model.  Any input here would be appreciated.

Basement air pulls about 25 amps when both compressors are running and about 15 amps when only one compressor is running (at least mine does. When I run basement and roof air, I draw 42 amps. At 120 volts, that's 5040 amps. With a 30 amp breaker on one leg, you may be able to run the basement compressor and roof compressor on the same circuit of the generator, but it's iffy.

To those who don't understand why people do this, I had a 2000 Suncruiser where the basement AC cooled without a problem. My 08 Meridian, on the other hand would be in the 80s inside when it got hot. The new roof air makes a little noise, but it's a really cool noise.

Kevin, no you are not the only one here that is satisfied with basement air. I can see that 40 footers need more BTU,s and am a little confused as with Frontrangers problem being the same unit as I have. I certainly believe him. I also have a 35 foot  2006 Voyage & have been pleased with the basement air. If the evaperator is freezing up on Frontranger,s  I would think he is correct that not enough air is going past it to exchange the heat. I would think something is not right in the duct area. Not that Winnebago would ever make a mistake in there construction! I also like the clean roof look when I pull into some not big rig friendly low limb RV parks. I can recall one park in PA where one limb scrapped accross my entire roof bending all sorts of things.  Could you some how put a camera on a snake down the ductwork to see if Winnebago might have left something in them? Good luck Frontranger and let us know how it comes out. Art

My rig is newer, but the 2006 32' Meridian also cooled well.  I was a little worried when we bought the 2010 as it is 35' long and has an additional full wall slide on drivers side because of the issues some folks have had with the cooling in the larger units (like Johns).  But I must say that during the GNR in Iowa this year we suffered through some days of a heat index of 117 degrees.  As long as we kept the shades down, the awnings out, and the MCD shade down when the sun was in front of the rig, we stayed really comfortable.  We did have to run  the AC 24 hours a day most days due to the humidity. 

I do know that Winne upped the BTU of the basement airs the last few years and that helped a lot.  I think that the roof air is a great addition if you need it, and well worth the money.  Let us know how it turns out!

My basement air actually works BETTER in high humidity areas....it's the dry climates where the coils freeze up. 

I am tired of burning up in my '05 Meridian, 3 slides, as well.  Does a new roof air unit tie into the exisiting ductwork?......how do I find John Canfields installation vid.
Hot in Pa.

Here's the writeup although you will have to be contented with still pictures and text.  Maybe my next project will have video (still trying to figure out what the next project might be at this point.)

Welcome aboard - glad to have you on The RV Forum!

I silently say to myself every time I am in my coach and it is over 90 degrees outside but i am as cold as I desire due to my rooftop air addition, "Thank god for John Canfield's rooftop install write up".  Best thing I did.

Thanks for the kind remarks!

I took some pictures of my wire run install, and plan to post them here after the air conditioner is set on the roof.  It won't be fancy smancy like John's though.  ;D

I just ran a 12/2 wire from the roof opening to a 20 amp breaker in the box. I don't guess I have to do something special for the amps to show up on my one place amp reading?

Mark - nothing to do.  I think the current transformer is on the neutral side of the line and it will register any load that goes through the neutrals.  Maybe Gary can expound a little.

BTW, I can run the roof air on high cool, the basement air on two compressors and we're pulling about 40 amps - almost instant refrigerator  ;D

John, doesn't current in the neutral suffer by being cancelled out due to the two input 50A legs being on different phases? If that is so the measurement of current using the neutral would not likely be accurate, it seems to me... I have been known to be wrong.... often! though.

You don't have to do anything to activate the 2nd AC power draw on the amp display. As John stated, it is measured on the neutral return from the load center (breaker panel), so any power that goes through the load center is automatically included.

The One Place current display is inoperative when on a 50A hook-up, for the reasons  that Stu mentioned. The Intellitec (Powerline) controller recognizes 50A shore power and shuts down the amp measurement display. It is active only when on 30A or generator.

Mark,
Before you install the roof air you might want to crawl under the back end of the coach with a flashlight and take a look at the duct.  The basement air has a duct run between the outside fiberglass cap and the back wall. There is a common problem with the metallic tape on the duct loosing its adheasive and allowing the duct to open up. The duct is 1/2" styrofoam(I think) and it is insulated and held together with the metallic duct tape. In some cases you an repair it yourself an others you bite the bullet. The duct my Suncruiser had a slit(opening) about 18-24 inches long. We could not get the temp inside any lower than 10-14 degrees lower that the outside temperature. I could not reach the duct to do the repairs myself. I took it to the RV dealer where I bought it and they had to remove the rear cap to make the repairs. I have an extended warrenty so I only paid $100 instead of the total cost of $1950.00.         

Pretty certain Mark is aware of the ducting issues in the rear cap, but that's an important point to mention for others.  Thanks.

After I ran the 12/2 wire from the breaker box to the roof vent last week, yesterday my new Brisk Air 13,500 High Effeciency Roof Air was installed in place of the Fantastic Vent.  I am pleased with the installation (get this:  CAMPING WORLD) in Fountain CO, as the Service Manager was very helpful and knowledgable.  ;D

For the nay sayers that said I couldn't run my all three compressors on my Onan 5.5....um.....PIECE OF CAKE!  I have been running all three compressors on the gen for many hours, and the total amps are 34 amps (90 degrees low humidity outside).  I have no problem running all three compressors with the fridge and while the amps are close, I did do some hard starts on my roof air and never tripped either generator breakers.  Of course running all airs on 50 amp shore power is no problem, and I was able to use the water heater and fridge withouth any load shedding.  I haven't tried the microwave with all the other appliances, but if I do, I most likely will manually shed Comp. #2 on the basement air before I do.  All the generator testing was done at an altitude of approx 5,000 with outside ambient temps of approx 90 degrees with low humidity.  PS, the new Roof air has only a 10 amp draw. 

I have been down in Altitude, parked at an RV park for my testing, and outdoor temps of 90 degrees, inside temp of 69 degrees.....AHHHHH!  The bliss of nice cool air!!!!

And here it is.....I wish I would done this sooner! 

PS...the new High efficency unit AND installation was $870.