13.5 k or 15 k BTU for 19' trailer?

[Ruscal]

We are new owners of a Bambi 19' that had a damaged Dometic Penguin AC. I am seeking a suitable replacement and wonder if a 15000 btu unit would be desirable over the stock 13500 unit, or would it be too much cool? The cost difference is only about $100.00. We have 2 Honda 2000i gennies. I have read hundreds of posts regarding this debate, but all of them were regarding 25' to 40' trailers. Does anyone on the forum own a 19'?
Russ

[xrvr]

You could go with a single 11000 unit and run it off one generator.

[Peanut]

Originally Posted by avionstream

You could go with a single 11000 unit and run it off one generator.

Wish it would, but my Honda 2000 won't run Peanut's 11000 unit.

[xrvr]

Okay then try a 9000 unit, it's a tiny trailer. The 11000 should run off a 2000, I think.

[55AS]

I cool my 22 ft Flying Cloud with a 12,000 BTU and it provides plenty of cooling even in the Texas heat and humidity. Of course it is a split system inverter style A/C which runs easily on single (propane) Honda 2000.

[Adventure.AS]

Originally Posted by Ruscal

... I am seeking a suitable replacement and wonder if a 15000 btu unit would be desirable over the stock 13500 unit, or would it be too much cool? ...

As well as cooling you want your air conditioner sized properly so that it will dehumidify the air too. Modern air conditioners dehumidify as they cool; you can see that by the water that drains away, but this dehumidification is incidental to their main job of controlling temperature. They cannot independently control both temperature and humidity. If an ac unit is too large for the space it will cycle on and off too often as it can easily cool the air, but to remove humidity the ac should have to 'work hard', i.e. run longer and/or more often. Sometimes smaller is better.

Do not set your thermostat to the “fan on” position. In this position the fan blows air all the time whether your cooling system is running or not and one key impact is that a lot of the moisture your system just took out of the air, will be blown back into the coach before it can drain way.

[A W Warn]

Originally Posted by Ruscal

We are new owners of a Bambi 19' that had a damaged Dometic Penguin AC. I am seeking a suitable replacement and wonder if a 15000 btu unit would be desirable over the stock 13500 unit, or would it be too much cool? The cost difference is only about $100.00. We have 2 Honda 2000i gennies. I have read hundreds of posts regarding this debate, but all of them were regarding 25' to 40' trailers. Does anyone on the forum own a 19'?
Russ

There is no need for a larger unit in your trailer.
If it were me, I would install an exact same replacement. That way all of the wiring and the condensate drain will fit perfectly without modification. It should cost less for install labor if it's plug and play. A pro can change it out in around an hour.

[KWN306]

The smaller unit requires an 15 amp circuit, the larger unit requires a 20 amp circuit. Which means the wiring would need to be replaced as well as the circuit breaker.

Stick with what the AS guru's specified unless you have more money than brains.

[Ruscal]

Originally Posted by BambiTex

I cool my 22 ft Flying Cloud with a 12,000 BTU and it provides plenty of cooling even in the Texas heat and humidity. Of course it is a split system inverter style A/C which runs easily on single (propane) Honda 2000.

I think those split units are more efficient than the low profile Dometic Penguin ll units. I also have a 16' Scamp with a 9000 BTU Mini Mach that I have not tried to run with one 2000i. It might start it but we always ran 2 gens.
Russ

[Ruscal]

Originally Posted by A W Warn

There is no need for a larger unit in your trailer.
If it were me, I would install an exact same replacement. That way all of the wiring and the condensate drain will fit perfectly without modification. It should cost less for install labor if it's plug and play. A pro can change it out in around an hour.

Thanks Alan,
You may be right about not needing more cooling. Most posters with 25 footers were wanting more cooling than 13.5, but their cabins are 6' longer than mine and the air wouldn't travel to the far end. Some of those people chose the 15k option over adding another unit.
The install is identical for both units. Same drain kit, and layout. The factory provided 12 gauge wiring and a 20 amp breaker in my trailer. The actual current draw would be higher with the 15k unit, but the 2 gennies would run either.
Russ

[Ruscal]

Originally Posted by Adventure.AS

As well as cooling you want your air conditioner sized properly so that it will dehumidify the air too. Modern air conditioners dehumidify as they cool; you can see that by the water that drains away, but this dehumidification is incidental to their main job of controlling temperature. They cannot independently control both temperature and humidity. If an ac unit is too large for the space it will cycle on and off too often as it can easily cool the air, but to remove humidity the ac should have to 'work hard', i.e. run longer and/or more often. Sometimes smaller is better.

Ray,
I remember hearing this before about AC systems function better when having to work harder.

Do not set your thermostat to the “fan on” position. In this position the fan blows air all the time whether your cooling system is running or not and one key impact is that a lot of the moisture your system just took out of the air, will be blown back into the coach before it can drain way.

I read something about the newer Dometic thermostats can cycle the fan with the compressor or have both shut off together when cycling. When set to "auto" it leaves the fan running (I think). I do have to change the old 5 button thermostat to a digital ccc2 to work with the Penguin 2, so will have to learn what all those buttons do.
Russ

[xrvr]

Originally Posted by KWN306

The smaller unit requires an 15 amp circuit, the larger unit requires a 20 amp circuit. Which means the wiring would need to be replaced as well as the circuit breaker.

Stick with what the AS guru's specified unless you have more money than brains.

Is that true?

[A W Warn]

Originally Posted by avionstream

Is that true?

No.
This is link to a brochure that states that a 20 amp circuit is specified for all Dometic Penguin units.
http://dometic3frontend.qbank.se/epi...031957a824.pdf

[xrvr]

Thank you.

[1973Argosy]

A single 13500 keeps my 24` very comfortable.

[Al and Missy]

Our 2001 Safari 25 had a 11,000 BTU unit which was completely adequate and would run from our single EU2000i Honda. Planned to test the voltage sag and current drain when starting to ensure that the compressor was not being stressed but never did it before I traded trailers. The 25 had the "mousefur" walls and vinyl ceiling. I think that contributed to the insulation factor over the newer exposed aluminum walls.

I'd put in whatever was originally there and expect it would be fine for cooling in most, if not all locations. As was mentioned previously, you don't want to go much oversized or you will not be removing humidity adequately.

Al