Portable AC vrs Roof AC

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djw2112

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I can get a portable AC that plugs into the RV outlet which says it will cool a space larger than my 24ft RV.  This might save me a ton on my electric bill in the summer time by leaving the roof AC off or limit it's use.  Anyone try this idea and was it successful?
 

SpencerPJ

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The portable one still uses electricity  :eek:

I thought the portable ones needed a window to vent the exhaust as well.  I was always under the impression they were not the most efficient way to cool, but better than nothing.
 

grashley

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My concern is also efficiency of the portable unit.  How does it exhaust the heat it removes from the air?  What does it cost to run the unit?  (wattage vs roof top)
 

rbTN

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I can't say how it will work in an RV, but I use one in my home office (servers put off a lot of heat) and it works, but it uses a lot of air movement to do it. Meaning it exhausts a lot of air while cooling the room. I would think an RV AC would be more efficient simply by not bringing in un-conditioned air like a portable will require.
 

djw2112

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I found quite a few but here is one that i think will do the job. 

lowes.com/pd/Honeywell-400-sq-ft-115-Volt-Portable-Air-Conditioner-with-Remote-Control/999901017

I spend approx $1300 on electric over the summer time for 7 months using the roof AC which I am sure uses alot more power than this portable unit would use.  Maybe it might pay for itself in just 3 months if it does the job.
 

cavie

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djw2112 said:
I found quite a few but here is one that i think will do the job. 

lowes.com/pd/Honeywell-400-sq-ft-115-Volt-Portable-Air-Conditioner-with-Remote-Control/999901017

I spend approx $1300 on electric over the summer time for 7 months using the roof AC which I am sure uses alot more power than this portable unit would use.  Maybe it might pay for itself in just 3 months if it does the job.

You know what P.T. Barnum said right?
 

SeilerBird

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djw2112 said:
I found quite a few but here is one that i think will do the job. 

lowes.com/pd/Honeywell-400-sq-ft-115-Volt-Portable-Air-Conditioner-with-Remote-Control/999901017

I spend approx $1300 on electric over the summer time for 7 months using the roof AC which I am sure uses alot more power than this portable unit would use.  Maybe it might pay for itself in just 3 months if it does the job.
I had a 32 foot class A with a roof mounted air. It was not sufficient to cool the entire RV. So I bought a 5k window job and put it in the bedroom. It did not cool the entire RV either, but it cooled the bedroom when I was in bed and the living room when I was in there. The big advantage of the window unit was the remote control.
 

ArdraF

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Could you use it while driving down the road like we do our roof-mounted unit?  If djw2112 lives in or goes to the desert that might be a big factor.  When it's over 100 degrees the dash air simply can't handle the cooling with the large windshield.  We run our roof air to keep it reasonable.

ArdraF
 

Willandgiselarv

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I have 3 of them , what I will tell you is the single hose unit is not as efficient as the dual hose units.
When you shop for them look for the units with 2 hoses.
In fact a 13k portable AC is equivalent to a 10 or 8k window a/c.
The portable ones are just more convenient to move around.
 

cavie

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djw2112 said:
I found quite a few but here is one that i think will do the job. 

lowes.com/pd/Honeywell-400-sq-ft-115-Volt-Portable-Air-Conditioner-with-Remote-Control/999901017

I spend approx $1300 on electric over the summer time for 7 months using the roof AC which I am sure uses alot more power than this portable unit would use.  Maybe it might pay for itself in just 3 months if it does the job.

Compare the Electric wattage of your roof air and the unit you want to buy and get back to us.
 

djw2112

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I compared the two as much as I could, here are the results.

I have a Brisk Air 57915.531 roof AC


                        portable                                              roof

BTU                  10000                                                13500
elect                  115/  ?Hz                                          115/60Hz
amps                9.5                                                    12.7
sq ft coverage  400                                                    450


I did a BTU calculator for my RV and it suggested a 12870 BTU.  So I am thinking this portable may work for what i want to use it for.  Mostly leaving the roof AC off at night and also when watching TV, unless it is really needed.



 

Back2PA

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As others have stated, the portable units are not as efficient as the rooftops, and therefore aren't likely to accomplish your stated goal of saving money. In fact, it could end up costing more to operate, plus the cost to purchase.
 

cavie

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djw2112 said:
I compared the two as much as I could, here are the results.

I have a Brisk Air 57915.531 roof AC



I did a BTU calculator for my RV and it suggested a 12870 BTU.  So I am thinking this portable may work for what i want to use it for.  Mostly leaving the roof AC off at night and also when watching TV, unless it is really needed.

It will not work in the daytime. If it would the manufacturer would have installed a cheaper smaller unit.
 

djw2112

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I will seek a more BTU unit.


I do understand that the portable is not equivelant to roof top but I am thinking that the portable might be better at initial load required at start which might be where the savings is seen.  We all know that roof units take alot to get started which is why they are on a 15 amp fuse in the panel.  Is it wrong to think the portable unit would use alot less power to get started?
 

cavie

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djw2112 said:
I will seek a more BTU unit.


I do understand that the portable is not equivelant to roof top but I am thinking that the portable might be better at initial load required at start which might be where the savings is seen.  We all know that roof units take alot to get started which is why they are on a 15 amp fuse in the panel.  Is it wrong to think the portable unit would use alot less power to get started?

Tell us what the amp draw or watts is of the unit you want to buy. Your existing unit uses 12 amps on a 15 amp circuit. More on start up.  Compare the amp draw of a portable with the same size BTU of your roof top. Then tell me how you think it will be cheaper. Also remember, your roof top is on a circuit by itself. Your portable will be on one of your 2 available circuits in your trailer taking up most of the available power on that circuit.


 

John From Detroit

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The roof A/C is likely more effiencent and the wiring in the RV may not be up to handling ther portablr (Depernds on how much the portable eats  I like to limit to 10 amps on RV outlets)

The Roof top uses outside air to cool the condenser. the portabler needs to be vented if you do that so the roof is way better choice. there are additional reasons as well.
 

Gary RV_Wizard

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Frankly, I think you are dreaming. The portables are use as much or more power than a roof unit to produce the same btus, so there is no gain there. Even if a smaller btu portable is used, it still has to run x hours/day to pruce the btu-hours to cool the place and will simply run lnger than a larger unit doing the same job.

RVs are horrible to heat or cool and require many more btu-hours per square ft than a house or apartment. RVs rapidly gain heat, especially in the sun, and have a much higher percentage f windows to wall area. Even a small RV needs 13k-15k btus of a/c and it will run most of the time during any hot day or in direct sun.  Once night comes, the typically don't run all that much and power consumption is modest.

Add to that the loss of the very limited floor space and the nuisance of routing the portable ducts (in & out), and the whole idea is a loser.
 

Gizmo100

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Sep 28, 2018
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I think a better investment might be in making the RV more efficient.
Check all doors and windows for tight seals
Check all plumbing/electrical entry points for air leaks
Cover all window with curtains that block sunlight to reduce solar heat buildup inside.
limit use of heat producing items in RV. (Computers produce a lot of heat)
If possible moving RV into a shaded area.

I think you get the idea.

I with the others....Your trading apples for apples
 

wmtired

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Oct 27, 2018
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I had a small 15 foot long or slightly less solid wall hydraulic popup camper and the small residential air conditioner in it just didn't do the job.  With that said, I thought about installing a small residential unit under my kitchen sink which is adjacent to my bedroom in my 5th wheel on the assumption that my 15k BTU ducted RV airconditioner wouldn't cool my bedroom sufficiently in hot weather.  I can safely say that by partially closing the vents in the living room, I was able to sleep at a comfortable 68 deg in hot and humid Texas heat!


What camper am I talking about?  A Fold-N-Roll made by Irv Perch (RV Pioneer).  I wish I never sold it as it was very lightweight and was easily towed by my diesel Jeep Liberty. 

Here is vid of one looked like:  https://www.bing.com/videos/search?q=fold-n-roll&&view=detail&mid=5ACDC0919C63054B815F5ACDC0919C63054B815F&&FORM=VRDGAR This video shows one with an installed roof airconditioner which I wish I had when I owned it.
 
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