Upgrade from 13.5k air conditioner to 15k

[Bottomland4x4]

We just got back from a beach trip and there was some record hot temps and the air conditioner on my toter seemed to not get the toter down to around 74 degrees. We were camped in the direct sun which didn't help any, but I was thinking of upgrading to a larger unit. My toter is an 04 so the ac is over 11 years old. I only have a 30 amp service and was told by camping world that I would need a 50 amp service with the larger ac.

My ac unit has been cleaned with the coil cleaner as it was used for dirt track racing and was filthy when I got it. Is it possible to have the freon checked and see if it's low? I guess it's like a home unit?

[jasong]

The Freon can't be checked as they don't have pressure taps.
Check the amp draw of the unit you're looking to buy,I can't see it drawing that much more.
Post it and I'll let you know.

[Bottomland4x4]

It's a Coleman 15kbtu it says max draw of 16 amps.

[Bottomland4x4]

Looks like my old ac draws 14.9, not a lot of difference? I wonder how much the bigger ac will cool the toter? Will it run less and cool off faster?

[Mntom]

A pressure tap can be added quite easily to check the refrigerant, but chances are there is no need. If it had a leak it would probably be near empty by now. The larger AC unit will do quite a bit more to cool things down since it is just over one ton more cooling (a ton of cooling is 12,000 btus). The only problem I can see is it might be tough to get enough airflow across the evaporator. To little air flow and it will frost up and you will loose the cooling. I have that problem with my 13.5k btu unit. I need to keep the 'fast cool' shutters open just a little. My trailer only has 6 3" outlets in the ductwork.

[superbird03]

I did a lot of research on the ac units as I just bought one for my new build.... Was debating on going between the 13.5 and 15. After talking with the Dometic folks I bought the 13.5. The compressors are the same on the 2 units. The only difference is the 15k has a slightly larger condenser/exchanger. They told me both are going to drop the outside temperature the same amount, between 15 and 20 degrees. The larger one will do it a little quicker but not going to be able to make it any cooler inside. They use to make a real 15k unit that had a larger compressor in it but they stopped that a few years back as there wasn't that much difference apparently.

Hope it helps, that is what I could find from my research.

[Mntom]

I screwed up in my last post..... My math sure wasn't doing good then. There is a 1500 btu difference not a 15,000 btu difference. I am sure 1500 btus will help, but not a large amount.

[jasong]

16 amps is the maximum loss for a 20 amp branch circuit.
If it's a 20A breaker and #12 wire, you'll be fine.

[hot rod]

I used a Carrier 15K btu heat pump in my last trailer instead of a traditional a/c. 19' living quarters with zero wall or ceiling insulation and it kept up no matter how hot it got outside. Plus you have the added bonus of full 15k heat as well if you need it. Your rv dealer is going overkill to tell you 50 amp is needed for a single a/c even if it is 15k, 30 amp is plenty. We had one event every year that we ran on 200' of 12 gauge cord on a 15amp outlet and did fine. Of course you have to remember to shut off the a/c to run the microwave etc. in an extreme situation like that.

[Bottomland4x4]

Went ahead and got the 15k btu, it was only $50 more dollars so I thought why not. Going to the beach on the 16th of august for a week, so it will be a good test for the ac. If I can tell any difference I will share it with y'all.
Thanks
Eric

[Bottomland4x4]

I forgot to add that the fan motor quit in the ac unit, it would start up and just slow down and throw the breaker. This was on a racing trip in sc, went out about 1am in the morning! Luckily the race was over kinda early and we came home a day early.

[Mntom]

The fan motor quit on your new AC?

[Bottomland4x4]

No it was actually the old ac unit, it seemed like it had a hard time keeping our unit cool at the beach. And then our next trip racing the motor locked up, it would start out then slow down and kick the breaker. After I replaced the entire unit it has worked fine.

[bushpilot]

Ive got two AC units on our coach a 15k in the rear and a 13.5 (roughneck) in the front.
i have no problem running (just) ONE of 'em off a 15a circuit (think curbside at MIL's).

[Bottomland4x4]

First full day camping at myrtle beach, temp in the 90s and ac kept it 72 inside all day. Ran a lot but we are parked in direct sun with no shade. It seems a lot quieter than the old unit too. We are camped in Lakewood and the next campground over I saw a renegade motorhome conversion. We don't see many conversions at a general campground. Lol!

[Mntom]

Glad to hear it worked out well for you! I wish there was something to do to quiet mine down. Is there added insulation in your newer one that you are aware of?

[Bottomland4x4]

I don't think there is any more insulation?

[Mntom]

Mine is so loud that when the fan comes on you need to turn up the TV.