One A/C or two?

[The Gritz Carlton]

Buy two up front!! Twenty posts confirm this.

[dkoldman]

What if you see a coach that only has 1 AC with 30 Amp & 4000 Onan. Brand New

If I insist on 2nd Unit. What is the preferred method as to not affect warranty by Thor?

Also, is it assumed by all that whenever you do add a 2nd unit that you will never use both when boondocking or traveling down the road?

Other perplexing tidbits about trying to get a 2nd AC when it is not originally installed.

1. If you upgrade service from 30 to 50 amps, how does that impact the lower rated generator? I assume you can't update the generator to 5500 Onan.
2. Does it make sense to add 2nd unit as a 13.5k wired into existing 30 amp service; but manually only use & maintain one or the other at a time?
3. Would it make sense to actually remove a new 15k unit to be replaced by 11k unit and add a 2nd 11k in bedroom

I live in area where it can reach the 100s with great regularity; so a 2 AC is a must' I don't see many 28 - 30 footers with two units but most all claim to be prewired for a 2nd unit; but it does not make sense the manner to add.

[The Gritz Carlton]

If two A/C's are a deal breaker, don't buy that coach. Find one already set up for 2 units...or have a 2nd installed. The 4000 would probably run two A/C'a bit you wouldn't have any reserve for other appliances.

[dkoldman]

Originally Posted by The Gritz Carlton

If two A/C's are a deal breaker, don't buy that coach. Find one already set up for 2 units...or have a 2nd installed. The 4000 would probably run two A/C'a bit you wouldn't have any reserve for other appliances.

It is definitely a deal breaker for me.

My question was more so around the method of having it installed?

Given it is configured for one 15k unit and only has 30A service and 4KW Onan.

What is the optimum / preferred size of 2nd Unit and method of connection; to existing 30A service establish 2nd 30A service etc. Does either kill your warranty?

[SuperD]

A lot of owners who travel in the south seriously regret not have dual ACs, it get hot there!!! You CAN add a second AC with a lot of work and money but a 4000 watt generator will not run two units.

Much cheaper up front to buy a coach with dual ACs, will also add considerably to resale value.

[Richard]

Just depends. You want to be cool and comfortable, get 2.

[dkoldman]

Originally Posted by Richard

Just depends. You want to be cool and comfortable, get 2.

It is clear I need 2 and will get 2.

The question I am asking around the method of having a 2nd unit installed on a coach that is configured for one 15k unit, prewired for 2nd unit but only has 30A service and 4KW Onan?

What is the optimum / preferred size of 2nd Unit and method of connection; to existing 30A service establish 2nd 30A service etc. Does either kill your warranty?

During the interim I continue to look for what I seek with dual AC, but if there an effective way to have unit added to 30 amp service is what I am try to learn now. If there is a way it gives me more options, that is all.

I live in Dallas area, and struggle to understand why any dealer would order anything 28 ft and up with only one AC?

I am newbie, but Thor should have two ACs as standard for anything bigger than 29 ft. Only option should be two 11K BTUs & 4KW Onan or two 13.5K BTUS & 5500 Onan.

[Richard]

You can run 2 ACs with 30 amp, but not much else. Put refrig on gas and use propane water heater when running both ACs. Will have to turn off one AC when using microwave. No hair dryers or other heavy draw stuff. Rule of thumb is total watts divided by 120 volts to give amps required. Example 4000watt Onan divided by 120 volts gives you 33.3 amps available to rn stuff. But 4000 watt Onan will deliver less than 4000 watts. Draw of 2 ACs will be less than 15 x 2 except at compressor startup. So you are close limit.

[Lt Keefer]

Get one with 2. I have camped with one and survived, but I have also camped with 2 and it was not enough.

[Glensouth]

A 30 Ft motorhome is at the extreme for just one a/c. To be comfortable I would recommend two units.

[EVMIII]

I agree that a 4K should run two AC units, but you would be on the edge of popping breakers all the time. Any other 110ac draw would put you over your available amps. My ACE came with two AC units, 50 Amp service and a 5500K Onan (all must haves in our search). I have never priced it but upgrading to 50 amp or adding a second 30 amp service, upgrading all your wiring to handle 50 amp, upgrading generator would seem to be cost prohibitive. I guess you could add a 30 amp service and power with a secondary 2 or 2.5 K just to power additional AC unit, but it sure seems (as many have already stated) that finding a unit equipped like you like from the factory sure seems like a more effective option. Living down South I definitely appreciate my second AC. Best of luck with your project.

[thebigd123]

IMHO, two if possible. There are the obvious reasons of being able to handle whatever climate you wander into. However what I appreciate as a new to full timer is the option of running either front or back based on where or what we are doing at the time. For example if we are enjoying a movie in the front, rear only is on for less noise, reverse for sleeping.

[Pete'sMH]

If I decide to add a second unit I expect it will be under $1000 to do it. That’s with me doing the work. At his point though I’m thinking the one will be sufficient. It seems to be adequate up to the high 90s. I’ve been in hotter places and been a bit warmer in the late afternoon than I’d prefer but as soon as the sun goes down I’m chill again.

[mountainsam]

If at all possible get two. Another advantage is running the rear a/c if watching tv in the front or running the front a/c if sleeping in the back, or both when necessary. We carry a small tower fan with us to move the air as our vents don't do much of a job.

[lwmcguire]

Originally Posted by mountainsam

If at all possible get two. Another advantage is running the rear a/c if watching tv in the front or running the front a/c if sleeping in the back, or both when necessary. We carry a small tower fan with us to move the air as our vents don't do much of a job.

Absolutely 2

[blw2]

for me it depends I think on where you live and travel....and how hot it gets there at night.... and how long the hot stretches of time last.

If I had to choose between two rigs, lets say 35ft or less....one properly set up with two units or another with only one...I'd of course choose the double unit rig if all else was the same....of course...but to me it's not a show stopper.

issue of power, which has already been discussed, is significant....jurry rig it, convert to 50 AMP rig, etc..

I find that even here in hot humid florida we get by with the one unit in our 31ft. On hot days it can't keep up...especially if we start it with the house already hot....but park it in the shade and let the AC cool the house before the hottest part of the day we can make it work without too much problem. But I'm generally in the mid to upper 90's for a high here. Not more.

I found when travelling out west a couple summers ago to the high deserts through TX, NM, AZ that it generally got cool enough at night so that it was a complete non issue...even boondocking with open windows and no genny.

But get into 100 degree + weather, that would be a problem.

Also full time or part time. A person can generally deal with less than ideal for a few days, a week, or two.... but If we were full time I have no doubt it would get old fast.

That said...I've mentioned before that I wish someone made a small roof AC, something in the 5,000 -6,000 btuh range. I'd swap out my bedroom roof vent for that one in a hurry. I could still power it without too much problem, and I think it would be enough. Anything more is really overkill for a 31ish footer...but if you need it, go for it.

[Pete'sMH]

Originally Posted by blw2

for me it depends I think on where you live and travel....and how hot it gets there at night.... and how long the hot stretches of time last.



If I had to choose between two rigs, lets say 35ft or less....one properly set up with two units or another with only one...I'd of course choose the double unit rig if all else was the same....of course...but to me it's not a show stopper.



issue of power, which has already been discussed, is significant....jurry rig it, convert to 50 AMP rig, etc..



I find that even here in hot humid florida we get by with the one unit in our 31ft. On hot days it can't keep up...especially if we start it with the house already hot....but park it in the shade and let the AC cool the house before the hottest part of the day we can make it work without too much problem. But I'm generally in the mid to upper 90's for a high here. Not more.



I found when travelling out west a couple summers ago to the high deserts through TX, NM, AZ that it generally got cool enough at night so that it was a complete non issue...even boondocking with open windows and no genny.



But get into 100 degree + weather, that would be a problem.



Also full time or part time. A person can generally deal with less than ideal for a few days, a week, or two.... but If we were full time I have no doubt it would get old fast.



That said...I've mentioned before that I wish someone made a small roof AC, something in the 5,000 -6,000 btuh range. I'd swap out my bedroom roof vent for that one in a hurry. I could still power it without too much problem, and I think it would be enough. Anything more is really overkill for a 31ish footer...but if you need it, go for it.

X2 on wanting a small 5-6,000 BTU option. Haven’t found one yet. Came close with a small portable but not quite what I’m looking for. Maybe someday one will come on the market. I’d be all over it.

[rlcpe]

We are in AZ with a 31 ft Class C. Travelling to Oregon last year, one didn't cut it in the summer even up there. I have added a second 30A service, with adapters to go to a 15A plug if needed. Am putting in a Coleman Mach 3 PS AC unit, 13,500 BTU but normal running at 10Amp draw. I have spent $300 on the service, new 3oA panel and wiring up to the AC unit. Will be buying the AC for $650 +/- ( many places to buy) and having it installed for $300. Hope this helps.