RV News RVBusiness 2021 Top 10 RVs of the Year, plus 56 additional debuts and must-see units → ×

Thread Tools Display Modes
Old 08-11-2018, 10:01 AM   #21
Senior Member
Join Date: Jun 2012
Posts: 10,907
Originally Posted by myxkp View Post
Apologies for the misspelling. Auto complete got the better of me. It is properly spelled Psychrometric.
Spell check likes it either way!
1988 Coleman Sequoia - popup (1987-2009) - outlasted 3 Dodge Grand Caravans!
2012 Roo19 - hybrid (2012-2015)

2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado 1500 Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10
rockfordroo is offline   Reply With Quote
Old 08-11-2018, 10:08 AM   #22
Denver To Yuma In 90 Days
Join Date: Mar 2018
Location: Yuma, Arizona
Posts: 3,882
Originally Posted by myxkp View Post
Too many BTU,s is not good. Removes sensible heat faster than latent heat leaving high moisture behind. Look at the psychometric chart - this is the science behind sizing a/c units.
I doubt that the moisture thing is the issue...

I'm guessing that most decent size TT's or 5'vers with 30-amp service come with only one AC unit for two reasons.

The first...cost!

Cheaper to make the unit and a more inviting price for the end consumer (ie.- us).

The second reason would be that pushing a 13.5K AC on a 30-amp RV is already pushing the limits of the electrical service in the RV.

Try running a coffee maker, microwave and the AC unit at the same time and guess what typically happens?

Or just the electric water heater and AC together...


My 33-foot 5'ver has a 13.5K AC unit and 30-amp service, and it can barely keep up once the temps get over 90 degrees.

I live and travel the southwestern US of A.

Now I live in Yuma, AZ (after 26 years in Denver, CO)...it is 8:05 am right now and already 92 degrees outside.

I believe that a 15K AC unit would be better, but would still struggle with the heat.

And would probably pop the circuit breakers in the 5'ver.
JohnD10 is offline   Reply With Quote
Old 08-11-2018, 12:09 PM   #23
Senior Member
Bluepill's Avatar
Join Date: Jun 2015
Location: Pensacola, FL
Posts: 1,645
Yeah, my 13.5K BTU Dometic pulls 1670 watts per factory spec. sheet. (Also a lousy EER of 8.1 compared to window units in the high 11's). That leaves precious little extra for the converter and microwave. Using the 80% of maximum circuit capacity rule for steady loads results in a limit of 2880 watts for a 30 amp. service.

15K BTU is only an 11% increase in cooling capacity over the 13.5.
2019 Coachmen Freedom Express 192RBS
2015 T12RBST Flagstaff Hardside

Disclaimer: The actual value of my "Two Cents" of advice varies just like a bitcoin.
Bluepill is offline   Reply With Quote

3500, 500

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by


This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.

All times are GMT -5. The time now is 10:33 AM.