2018 27FB double or single air cond units?

[raybailey]

New the world of RV.
Purchasing a 2018 27FB globetrotter. Won't be traveling in extreme temperatures. Not sure whether 2nd AC unit is necessary. Any feedback pros and cons is greatly appreciated.

[CRH]

I have a 25 ft. In direct sunlight above 90 degrees, my AC works hard to get down to 80. I often shut the bedroom door off to let the front get cooler.

If I were buying a new trailer, it would absolutely have two AC units. First, to help with overall cooling. Second, so I would have cooling if one AC died during a trip.

Georgia is plenty hot, IMO. Get two ACs.

[HeavyAssault]

I'm getting two ACs since it adds the 50 Amp service to boot. 50amp trailers can be used in a 30 amp park/spot. Better to have and not need more power than expected.
Consider dropping some extras like the solar or power awning.

[aftermath]

I won't be of much help here. This is one of those decisions that will address where you plan to camp, how you usually camp and what year of trailer you are looking at. A 2018 has the ducted air and I understand that it is much more efficient that the old style like I have. You need to listen to those with newer units.

With the second AC you upgrade to a 50AMP service that has a heavier 50 AMP cord to deal with. Again, listen to those who have these.

If you spend all of your time in full hookup sites then the 50AMP should work. If you use state campgrounds and boondock now and then it won't help that much. We live in the Northwest where it does get hot but with the low humidity it also cools off each night. If I lived in the deep south I think I would be a 2 AC kind of guy.

[uncle_bob]

Hi

If you are in Atlanta, you *will* need the second AC for "short trip" camping. The 50A service (as noted above) is a major plus when you go for the added AC. Since it also goes from 120V to 240V feed, you actually get 100A at 110V with the "50A" hookup. That takes you from "I need to think about it" to "I don't care" in terms of turning this or that on.

There really is no downside to the 50A hookup. If the cord bothers you on a 30A site, you can get 30A cords that have 50A "trailer side" plugs on them. The 50A cord is a bit heavy, you get a great big one with the trailer. They do make shorter ones that will work for a lot of sites. You also should get a 50A to 30A adapter that lets you plug the 50A cord into a 30A pedestal. I also have a 50A to 15A plug adapter than lets me use a normal extension cord to power the trailer (with limited stuff turned on in the trailer ...).

Some data:

In the full sun / no shade at >95F and 30A service, there simply was no way to get our trailer down below the mid 80's. Yes it's a 30', but that's not a lot bigger than 27 in terms of heat loss. When we got to a location with 50A power, the trailer came down from 102 (yes !!) to 73 in about 2 hours.

The ducting in the "modern" trailers does help things a little in terms of noise and drafts. It also lets you run one of the two (you get to pick) AC's on a 30A site. If it's day, you likely run the one by the dinette end. At night you might still run that one (it's quieter).

Lots of things to think about !!!

Bob

[Mollysdad]

2 AC's was a must in my new 26U. Hard to find.
My theory was that it's better to have it and not need it than to need it and not have it.
I gave up the second Fantastic Fan, but gained 50 amp service.

[wulfraat]

Most definitely get get 2 ACs.

I've found that the ducted system is a little less efficient than the older "direct jet engine downdraft" style. Better overall for sure, much quieter, but a little less efficient.

For that size trailer you will need 2 ACs to be comfortable, they both share the same duct work, and 1 AC would struggle to move the volume of air necessary to cool the entire trailer even in moderate heat.

[Zybane]

Originally Posted by wulfraat

Most definitely get get 2 ACs.

I've found that the ducted system is a little less efficient than the older "direct jet engine downdraft" style. Better overall for sure, much quieter, but a little less efficient.

For that size trailer you will need 2 ACs to be comfortable, they both share the same duct work, and 1 AC would struggle to move the volume of air necessary to cool the entire trailer even in moderate heat.

I agree. The A/C seems to "cool the roof" more which is less efficient. IMO 2-AC units is required.

Plus 2 AC's bring some benefits that a lot of people don't think about:

50 AMP service
A backup one that can still cool some if one fails or needs service
On the more moderate days you don't need two AC's running, you can balance them for your living space. This means that you spread the wear and tear over two units, making them last longer.
Having two AC's means you can keep more of the noise in an end of the trailer you are not.

[wulfraat]

Good point on 50A service - allows one to run a lot of “stuff” all at once. Like electric hot water heater, microwave and an AC unit. Can’t run all that at the same time on 30A service.

[gypsydad]

Our first 3 25's we had single 1500 AC unit and I thought that would be fine for us. I do remember camping in Borrego Springs desert several times, and even though it was 90+, we were able to do fine in the dry air. I also remember going through Las Vegas in 118deg heat few years ago; was so hot, we decided to stay overnight in a hotel, since I could not get the AS cool enough--that was unique for us.

When we got our new 28' FC this year, it had 2AC's so it was not a choice for us to only have one AC, even though I really thought 1 AC would be sufficient.

Recently, we camped in Florida for a week in hot humid weather, and the second AC helped cool the unit down very quickly. I tried using just one, but it was taking too long, so I switched on the second unit.

I do not like dealing with the 50A power cord vs the 30A power cord, but I will tell you I like the 2 AC set up for anything larger then a 25'. Didn't think I would ever say that. Also can help for resale to someone in a "hotter" state; like FL or TX!

[uncle_bob]

Hi

One significant issue in AC performance - it's not just temperature. The amount of direct sun matters. The humidity matters as well. The more water in the air, the harder the beast has to work to cool the air down.

Comfort wise, humidity also matters. A trailer that is at 70F and 90% RH is not comfortable. An AC system that runs in short bursts is not going to do as good a job knocking down the inside humidity as one that runs longer. In some cases, switching from two AC's to one (or setting a temperature differential) will make things more comfortable.

Bob

[ArkFortyCal]

We have had both a single AC trailer and now a dual AC trailer. As someone mentioned above it comes down to when and how you use it. Our old single AC trailer did not have the street side awning option that our current trailer has, this will make a big improvement in temperature in the trailer on sunny days.

My wife and I still work so are a little dictated when we can use the trailer and if the temperature is 95+ we still want to go. With old single AC trailer this meant for some hot and sweaty days. Now with two AC's and the street side awnings we can be as cool as we want no matter the temperature.

I will comment that since we had the street side awning option on our new trailer we hardly ever have two AC's running at the same time (these have a huge impact on shading the trailer).

We mostly do what another poster mentioned above is run the opposite AC to where we happen to be in the trailer because of the noise (QuietStream ducted AC really means quieter but it's still a little loud). So at night we will run the living room AC when we are in the bedroom. In the Keys last year we did have both AC's running and were glad that extra one was there.

In Airstream pricing this isn't the most overly priced item (that would be 16" wheels and tires) and I think they charge a fair price for the extra AC (which includes moving to 50amp), so if you can afford it I would do it for sure.

If you are retired where you can chase good temperature throughout the year, maybe two ACs would not be needed.

Some extra thoughts.....we heard some comments about the size of the 50 amp cord, it's obviously larger than the 30amp but more manageable than I would have thought. That said my extension cord is only 30amp as it was only used twice this last year.

[pteck]

While 2 A/C's would be great for extreme temps. There is a tradeoff. Where the second A/C goes, would be a fantastic fan. I find myself using that second fantastic fan way more than I use the A/C at all. But certainly there are times, I wish for the second A/C.

I'm counting on upgrading my single A/C to a Blizzard NXT. It's the same 15k rating, but supposedly moves more air and is more efficient. That may be adequate for a single A/C.

[Desert Steve]

If the second unit distributes cool air through the factory ducting and operates as a second zone I would absolutely pay the extra.

Originally Posted by raybailey

New the world of RV.
Purchasing a 2018 27FB globetrotter. Won't be traveling in extreme temperatures. Not sure whether 2nd AC unit is necessary. Any feedback pros and cons is greatly appreciated.

[Journey'81]

When we were in the process of purchasing our 27' FB FC, the only unit with the color scheme we wanted has dual AC. Otherwise we will have to wait. Reluntantly (slightly), we agreed to go for the dual AC.

That was back in Feb 2017. Now we are glad to have the dual AC unit. AS does build up heat pretty fast in full sun at 80+F with no shade. In this situation a single AC will not be able to cool it down to enjoy in the trailer - don't want to be outside because of the heat.

There is another advantage with dual AC - AC redundancy. If one fails, we have a backup AC. Is a rare situation but it had happened to us twice. Yes the failed AC had been replaced once and is now in the process of replacing it again . Luckily both replacements were under warranty.

We are glad we have dual AC. Remember it is expensive to install a second AC if you do change your mind.