RV A/C Efficiencies

[Lt.Dan]

Anybody got some tips/ hacks to improving an RV AC efficiency?

I'm not an A/C guy by no means, and have little knowledge to how they even work. Is there any way to improve theyre efficiency? Either in terms of actual watt usage or colder/faster air flow to reduce compressor run time?

What makes an RV A/C use 2x the amount of power than a mini-split? For the same or less BTU?

 

[LB3]

The mini split has an inverter driving the motor so it can run a variable speeds to match your thermal load and the condensers and evaporators are probably larger reducing the airflow needs.

Some RV A/Cs are finally starting to incorporate inverter technology but it’s expensive and the largest volume manufacturers are serving the value side of the market. Advanced RV sells dozens of $400k RVs each year and their customers won’t think twice about spending an extra $3k for a quieter or more efficient A/C but the mass volume manufacturers that Dometic and Coleman serve are selling thousands of units in a price driven market.

 

[eXodus]

Anybody got some tips/ hacks to improving an RV AC efficiency?

I'm not an A/C guy by no means, and have little knowledge to how they even work. Is there any way to improve theyre efficiency? Either in terms of actual watt usage or colder/faster air flow to reduce compressor run time?

What makes an RV A/C use 2x the amount of power than a mini-split? For the same or less BTU?

terrible build format for starters, you have to get all the air in and out through a 12x12 inch opening.

Airflow in the plenum takes about a 30% toll but that can be optimized:

Products

Improve the performance of your RV air conditioner! Our system increases you’re A/C’s cooling by maximizing its transfer efficiency! EFFICENCY IS EVERYTHING! Cooling down your RV faster, Quieter, and more Comfortable! Coleman, Dometic, Furrion, & GE Air Conditioners ( Grand Design, Thor, Forest...

rvairflow.com

Single speed compressors are terrible in efficiency

Squirrel caged blowers are not very efficient. Literarily every component in mini split has formfactor which is optimized. While the RV air only follows design constraints - on the roof - little hole - must be cheap and fast to mount, should brake after the warranty is over.

 

[Partimewages]

If you have the new whisper quiet A/C the only way to improve air flow is to pull the unit off the roof. Our old Bighorn had 1/2 the air being recirculated from supply to return. It was installed poorly from the factory. I'm in the trades and have the tools to test and figured out that 1/2 the flow was missing. Took it apart and fabed up some light sheet metal with some silver tape and improved it a bunch. Did do anything for wattage but it ran a lot less which will save energy.

 

[fratermus]

What makes an RV A/C use 2x the amount of power than a mini-split?

My guess: the customer base is assumed to be on pedestal power in an RV park.

 

[Lt.Dan]

terrible build format for starters, you have to get all the air in and out through a 12x12 inch opening.

Airflow in the plenum takes about a 30% toll but that can be optimized:

Products

Improve the performance of your RV air conditioner! Our system increases you’re A/C’s cooling by maximizing its transfer efficiency! EFFICENCY IS EVERYTHING! Cooling down your RV faster, Quieter, and more Comfortable! Coleman, Dometic, Furrion, & GE Air Conditioners ( Grand Design, Thor, Forest...

rvairflow.com

Single speed compressors are terrible in efficiency

Squirrel caged blowers are not very efficient. Literarily every component in mini split has formfactor which is optimized. While the RV air only follows design constraints - on the roof - little hole - must be cheap and fast to mount, should brake after the warranty is over.

I am really considering buying the rv airflow stuff, but I'd have to buy 3, and at $170 each, it makes me cringe! Lol, but I suppose if it acts as advertised, it should be worth it.

Is there any way to adapt a variable speed compressor? Perhaps even a 48v DC model that would go with my 48v system in the RV?

I wonder if I could somehow modify the blower system to create more airflow?

 

[eXodus]

I am really considering buying the rv airflow stuff, but I'd have to buy 3, and at $170 each, it makes me cringe! Lol, but I suppose if it acts as advertised, it should be worth it.

Is there any way to adapt a variable speed compressor? Perhaps even a 48v DC model that would go with my 48v system in the RV?

I wonder if I could somehow modify the blower system to create more airflow?

Since my unit wasn't compatible with RV Airflow I've built my own variant of it with Rigid Foam insulation and HVAC tape
Just get the cover of the A/C and spend some time staring at the poor work.

Some of the design flaws are so obvious. Had to tape around the duct entrances and get some divider rigged. Probably not getting 30% like Air Flow - but it made a difference.

More Airflow is not necessary. A minisplit is only providing as much air as you need for the temperature. It runs at low airflow - but constant. While those roof blowers only know two modes - loud and off

When you got 3 units your best bet are actually closed doors. I know we all love our open floorplans - but sectioning of the RV and only cooling the part you are in is probably the cheapest way to save energy.

I got some programable thermostats and do 85 in the room when I'm away and 78 in the room I am.

 

[Zwy]

Anybody got some tips/ hacks to improving an RV AC efficiency?

I'm not an A/C guy by no means, and have little knowledge to how they even work. Is there any way to improve theyre efficiency? Either in terms of actual watt usage or colder/faster air flow to reduce compressor run time?

What makes an RV A/C use 2x the amount of power than a mini-split? For the same or less BTU?

Because it is extremely profitable for companies to manufacture and install substandard out dated technology?

Unless the end user demands a change, little will happen.

Maybe one of the best things occurring is people are attempting to have solar powered AC systems and it makes them realize just how inefficient some things can be. That will be the driving force for change.

Many products are out to help with moving airflow in a RV ducted system. The inefficiencies of the compressor and condensing units will still be there. The only thing you can do is to ensure the coils are clean and airflow isn't obstructed. A soft start will help with initial load at compressor start up. Start saving your money for the newer tech coming on RV and truck air conditioning systems. It's coming and will soon be more popular.

 

[Tdevery]

I did what eXodus did, on my AC unit. This did away with the shower down opening, All air now goes to each ducted vents. Major improvement for about $20. Search on the net for directions. Also much quiter.

 

[Ram5500 CamperThing]

For those that have mentioned the AC that Advanced RV sells...

After a lot of digging, i found it was a Houghton and ordered one for my build. Links to it installed and working in my signature

Its whisper quiet, and so far works great with my 300ah battery and Victron inverter.

Same that Advanced RV is using for 1/2 the price:

RV Air Conditioner Low Profile 13.5K Quiet AC Unit with Heat Pump, Remote, Non-Ducted

Are you tired of sweating in your RV during hot summer days? Say goodbye to discomfort and hello to the RecPro RV Air Conditioner! Our product is here to keep you cool and comfortable.

www.recpro.com

 

[Lt.Dan]

For those that have mentioned the AC that Advanced RV sells...

After a lot of digging, i found it was a Houghton and ordered one for my build. Links to it installed and working in my signature

Its whisper quiet, and so far works great with my 300ah battery and Victron inverter.

Same that Advanced RV is using for 1/2 the price:

RV Air Conditioner Low Profile 13.5K Quiet AC Unit with Heat Pump, Remote, Non-Ducted

Are you tired of sweating in your RV during hot summer days? Say goodbye to discomfort and hello to the RecPro RV Air Conditioner! Our product is here to keep you cool and comfortable.

www.recpro.com

Have you measured current used while this AC was running? The stats say 1550 watts when cooling, which is no better than my 15,000BTU unit now.

 

[Ram5500 CamperThing]

Have you measured current used while this AC was running? The stats say 1550 watts when cooling, which is no better than my 15,000BTU unit now.

Yes. It fluctuates between 900-1000 watts. I've seen it as high as 1100, but not over

 

[Tdevery]

wonder it would fit in my Fantastic vent opening?

 

[GSXR1000]

 

[GSXR1000]

major problem with efficiency is cool Square inches which they do not have

 

[Lt.Dan]

wonder it would fit in my Fantastic vent opening?

From what I have found, both the roof vents and the roof mounted ACs are mainly for a 14"x14" opening. So you can put an AC in place of a vent fan or vice-versa.

 

[Lt.Dan]

Yes. It fluctuates between 900-1000 watts. I've seen it as high as 1100, but not over

Thats good to hear, if I ever have a problem with my ACs, I will definitely replace them with something like this. Even a little loss in BTU isn't a huge bummer if I'm cutting 35% of watt usage.

 

[Ram5500 CamperThing]

wonder it would fit in my Fantastic vent opening?

Yes. They are both for 14”x14” openings

But note the exterior dimensions, it has a larger than usual footprint to keep it low profile

 

[Tdevery]

I might have to move a solar panel or two, to pit in a second AC. Just have to make sure the framing will support the extra weight.

 

[eXodus]

Because it is extremely profitable for companies to manufacture and install substandard out dated technology?

Unless the end user demands a change, little will happen.

Maybe one of the best things occurring is people are attempting to have solar powered AC systems and it makes them realize just how inefficient some things can be. That will be the driving force for change.

My perfect RV roof will be completely void of obstructions and penetrations.

No wonder that so many RVs have water-damage with all the random stuff on the roof.