Choosing between 13.5 and 15k btu AC

[lojoma]

We currently have a Carrier Air V 13.5 in our '73 Safari 23'. It does not do the job down here in the sunny South.

I am not certain how much of that is due to it being old and feeble and how much is due to it (maybe) being undersized.

It seems to pump out cold air pretty well, but you can barely feel the air flow a few feet from the unit. It cools the bedroom area somewhat, but the couch in the front just doesn't get any airflow.

We want to replace this unit no matter what, so I'd like opinions from others with AS models (who live in hot zones!) in this size range to see if 13.5 is able to cut it with a newer model AC.

I'm concerned that if I get the 15k, it will cycle too much and not remove the humidity well. But also concerned that 13.5 won't cool ENOUGH.

I am not able to put in a low profile unit because the rear ceiling vent is too close to the AC for it to fit. I'm mostly looking at the Houghton ACs for quiet and pretty high fan output rating, but welcome other options.

Thanks for any thoughts.

[richard5933]

A lot of this will depend on the electrical supply to the a/c unit. If it's not a proper 20-amp circuit, I'd stick with the 13.5 unit. If it is a 20-amp circuit with proper size wiring, then you have options.

[lojoma]

Originally Posted by richard5933

A lot of this will depend on the electrical supply to the a/c unit. If it's not a proper 20-amp circuit, I'd stick with the 13.5 unit. If it is a 20-amp circuit with proper size wiring, then you have options.

It's a proper 20-amp circuit. Thanks.

[FloydCoVa]

Maybe this will help.

https://www.airforums.com/forums/blo...all-done-2974/

[lojoma]

Originally Posted by FloydCoVa

Maybe this will help.

https://www.airforums.com/forums/blo...all-done-2974/

Yes, I did see that one, thanks.

[uncle_bob]

Hi

Going from a broken-down old A/C to a fully functioning new one will always be an upgrade. Performance wise, there really isn't a massive difference between the two. Sure, the 15K will do better, but only by a bit in terms of cooling.

Bob

[pteck]

If I'm not mistaken, the '73 vintage of Airstreams are narrow body? At 23', sure sounds like a space a modern A/C in good working condition should be able to handle without issue.

Mothership would fit a 13.5k unit. That should be enough but it also really depends on where you visit, humidity as you mentioned, and awnings/shade.

Most units have a high and low fanspeed? Perhaps getting a larger 15k unit and having two speeds may give enough adjustability for conditions?

[lojoma]

Thanks for the opinions, all.

I ordered the 15k. Wife is a polar bear and likes it cold as possible. We shall see!

[FloydCoVa]

Keep us posted!

[lojoma]

I went with the 15K Houghton from RecPro.

Got it installed today. Seems to work great (nice powerful fan) but it's too cool today to really assess how the AC works yet.

(Pic with ladder is from taking off the old Carrier unit.)

[restomod]

Do you have any videos to show how loud it is? Several people have asked in other threads.

Also, how is the cooling compared to your previous unit? Is it distributing air to both ends well enough?

[lojoma]

Originally Posted by restomod

Do you have any videos to show how loud it is? Several people have asked in other threads.

Also, how is the cooling compared to your previous unit? Is it distributing air to both ends well enough?

We haven't had the camper on the road yet to test it. When I ran it for about 30 minutes in our driveway, the fan was certainly more powerful...you could feel the airflow on the front gaucho, which you couldn't before. It also can point straight down so standing under it gives a nice cold air blast. It was pretty quiet compared to the old one. Almost too quiet, in the sense that you can't hear when the compressor kicks in. We could have a conversation in the camper. I would compare the noise level to a box fan on medium...definitely noise, but not terrible.

[lojoma]

Ok, so we were out this weekend and I have some more feedback.

First, it's still quieter than our previous AC but still fairly noisy. I was mainly evaluating it from the couch before. Standing under it (mid camper), I have a little difficulty having a conversation with my wife over on the couch (front of camper).

It does a nice job cooling, but it wasn't especially hot yet. We did use it overnight on the heat mode when it got below 50°. I thought that was a nice feature and worked well.

My one frustration is that it takes a long time to start up after you put it in cool mode. The manual says it takes a few minutes as a compressor protection feature, but it seems to be much longer than previous ACs we have had. It's warm, you want to cool off, and you are waiting for it to start up, wondering if it's going to work. I'm sure we will get used to it.

Ok, second frustration is with the AC fan function. I thought (based on other posts) this would have the ability to choose between the fan staying on all the time, or the fan stopping when the compressor stops (like a home AC). It does the latter and appears only to do the latter. The fan choices are Auto, low, med, high. The auto just seems to pick the fan speed for you depending on how far it has to go to reach the temperature you set. The fan turns off when the compressor stops for all of the fan modes. Just an FYI in case this is something that is important to you. (And maybe I'm doing something wrong with the settings?)

[FloydCoVa]

Thanks for the update…good info.

[jondrew55]

As a rule of thumb, you should have a 20 degree drop between the air going into an AC unit and the air coming out. This is easy to do with a meat thermometer. I do this at home too. There are little holes in my supply and return air in our AC units and it's a great measure of health for the system.

[lojoma]

Some more follow-up.

Now that it's hot out, we are using the AC all day. It runs well and cools well when it's turned down to a temp well below what it can actually achieve (say 65° during the day). But when it's set to a temp where it can reach and it cycles on and off, we have trouble. After it cycles off, it's a good 10 to 15 minutes before it cycles back on. And as I say above, the fan cuts off with the compressor, so it gets stuffy pretty fast.

I emailed RecPro about this and they are sending me a new control board. Hopefully this will fix the issue. Kudos to RecPro for responding quickly to my messages and addressing my concerns.

[lojoma]

Success! The new control board fixed the problem.

The fan now continues to run when the compressor cycles off.

When at the set temp, the compressor will cycle on for about 6 minutes then
off for 2 minutes.


If we turn it on, there is only about a minute and a half delay before the compressor starts, and again the fan starts immediately.

Much much happier with this now.

Good service from RecPro on sending the new board
as well as a small refund for the trouble.

[Wazbro]

That is good service, especially with the refund. If they didn't have you send the not so good board back I'd keep it for a backup or maybe sell it to someone who hates the fan not shutting off.

[lojoma]

Originally Posted by Wazbro

That is good service, especially with the refund. If they didn't have you send the not so good board back I'd keep it for a backup or maybe sell it to someone who hates the fan not shutting off.

Not a bad idea, but the not cycling correctly error is a biggie.