Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 05-13-2016, 07:19 AM   #1
Junior Member
 
Join Date: Mar 2016
Posts: 20
New A/C, 13.5k or 15k?

I'm getting ready to replace the A/C unit on my 1992 Fleetwood southwind 30'. It came with a 13.5k unit and I assume it cooled fine (has not worked since I bought it a few months ago). I'm wondering if I should step up and get the 15k unit or just stick with the 13.5? My motorhome has a 30 amp service and has the 4000w generator. I do use the motorhome to pull my race trailer with so I need to make sure the generator will pull the bigger unit. I guess my question is, is it asking too much to run the 15k on a 30 amp service and a 4000w generator?

Thanks!
__________________

__________________
Jason1955 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-13-2016, 08:30 AM   #2
Senior Member
 
jacwjames's Avatar
 
Monaco Owners Club
Join Date: Jun 2014
Posts: 4,597
Check the spec's on your old AC unit versus a new one. The newer ones are more efficient and draw less power then older ones. You may be able to upgrade to a 15K and still be using less power.

The 4000 Watt generator should be able to provide 33 amps of power at peak, probably ~27 continuous, which is plenty to run a 15K generator. Your coach probably doesn't have any significant parasitic draw so you should be fine either way.

In the long run it's all about power management. No matter what if you try to run too many appliances you will overload. Learn what the draw is on each appliance and balance to stay under.
__________________

__________________
Jim J
2002 Monaco Windsor 38 PKD
2005 Jeep Grand Cherokee w/5.7 Hemi
jacwjames is offline   Reply With Quote
Old 05-13-2016, 08:41 AM   #3
Senior Member
 
Join Date: Feb 2010
Posts: 4,492
Newer ones often may use same compressor but only have different size heat exchangers.

Reducing variability in parts reduces cost

Newer compressors much better than old ones too.

Look at the spec sheet for current one.

New one likely less amps used than old and larger unit likely less as well.

Last time we looked the difference was too small to cate and the better cooling well worth it.


However newer ones seem to be louder than old so visit a sales yard and take a few ac units for a test drive.
__________________
Tony & Lori
1989 Country Coach Savannah SE
TQ60 is offline   Reply With Quote
Old 05-13-2016, 11:16 AM   #4
Senior Member/RVM #90
 
MSHappyCampers's Avatar


 
Monaco Owners Club
Join Date: Nov 2002
Location: Columbus, MS
Posts: 26,245
I would definitely go with the 15K! I had to replace one a couple of years ago and went with the 13.5. BIG mistake!

Kinda reminds me of the commercial "I could'a had a V8"
__________________
Joe & Annette

2002 Monaco Windsor 40PBT, 2013 Honda CRV AWD
MSHappyCampers is online now   Reply With Quote
Old 05-13-2016, 11:53 AM   #5
Senior Member
 
Join Date: Oct 2010
Posts: 103
Price wise is only around $100.00 difference between the two.
__________________
kvm1970 is offline   Reply With Quote
Old 05-13-2016, 11:57 AM   #6
Senior Member
 
Join Date: Feb 2010
Posts: 4,492
Go big
__________________
Tony & Lori
1989 Country Coach Savannah SE
TQ60 is offline   Reply With Quote
Old 05-13-2016, 12:07 PM   #7
Senior Member
 
TonyDi's Avatar


 
Join Date: Feb 2011
Location: Point Pleasant Beach, NJ
Posts: 10,421
If you plan on being anywhere near hot weather, I'd go for the 15k.
__________________
Tony & Ruth........... FMCA#F416727
Newmar Dutch Star 4320, Spartan MM Chassis, Cat C9, Jeep Grand Cherokee Hemi, Blue Ox Aventa LX, and Brake Buddy. TST 507 TPMS
TonyDi is online now   Reply With Quote
Old 05-13-2016, 02:12 PM   #8
Senior Member
 
vsheetz's Avatar


 
Fleetwood Owners Club
Ford Super Duty Owner
Join Date: Jun 2012
Location: SoCal
Posts: 11,778
Go for the 15K unit, IMHO.
__________________
Vince and Susan
2011 Tiffin Phaeton 40QTH (Cummins ISC/Freightliner)
Flat towing a modified 2005 Jeep (Rubicon Wrangler)
Previously a 2002 Fleetwood Pace Arrow 37A and a 1995 Safari Trek 2830.
vsheetz is offline   Reply With Quote
Old 05-13-2016, 03:01 PM   #9
Senior Member
 
Brad Felmey's Avatar


 
Newmar Owners Club
Join Date: Apr 2016
Location: Wherever we're parked
Posts: 252
I just emerged from this decision as well. My investigations centered upon the Dometic Brisk II Air Conditioner (not heat pump variant) units, which come in 13.5k and 15k BTU versions.

The 13.5k BTU unit has a current draw of 15.3A (110v).
The 15k BTU unit has a current draw of 16A (110v).

The circuit in your RV for the A/C unit is most likely a 20A (it is in mine), with at least 12ga Romex wiring (rated for 20A continuous). Rule of thumb is to stay at 80% or less of a circuit's lowest-rated component, so the 16A of the larger 15k BTU unit is right on the money.

So, my analysis said that there was no problem with electricity supply, the units are physically interchangeable, use the same thermostatic control units, and the price difference is manageable (about $90). For this Texas boy that made the decision to purchase the larger one pretty easy.
__________________
Brad Felmey
Non-Retired Full-Timer
2018 Tiffin Allegro RED 33AA
Brad Felmey is offline   Reply With Quote
Old 05-13-2016, 03:38 PM   #10
Senior Member/RVM #90
 
MSHappyCampers's Avatar


 
Monaco Owners Club
Join Date: Nov 2002
Location: Columbus, MS
Posts: 26,245
Quote:
Originally Posted by Brad Felmey View Post
I just emerged from this decision as well. My investigations centered upon the Dometic Brisk II Air Conditioner (not heat pump variant) units, which come in 13.5k and 15k BTU versions.

The 13.5k BTU unit has a current draw of 15.3A (110v).
The 15k BTU unit has a current draw of 16A (110v).

The circuit in your RV for the A/C unit is most likely a 20A (it is in mine), with at least 12ga Romex wiring (rated for 20A continuous). Rule of thumb is to stay at 80% or less of a circuit's lowest-rated component, so the 16A of the larger 15k BTU unit is right on the money.

So, my analysis said that there was no problem with electricity supply, the units are physically interchangeable, use the same thermostatic control units, and the price difference is manageable (about $90). For this Texas boy that made the decision to purchase the larger one pretty easy.

Wise decision!
__________________
Joe & Annette

2002 Monaco Windsor 40PBT, 2013 Honda CRV AWD
MSHappyCampers is online now   Reply With Quote
Old 05-13-2016, 05:14 PM   #11
Senior Member
 
Brad Felmey's Avatar


 
Newmar Owners Club
Join Date: Apr 2016
Location: Wherever we're parked
Posts: 252
Quote:
Originally Posted by Brad Felmey View Post
I just emerged from this decision as well. My investigations centered upon the Dometic Brisk II Air Conditioner (not heat pump variant) units, which come in 13.5k and 15k BTU versions.

The 13.5k BTU unit has a current draw of 15.3A (110v).
The 15k BTU unit has a current draw of 16A (110v).

The circuit in your RV for the A/C unit is most likely a 20A (it is in mine), with at least 12ga Romex wiring (rated for 20A continuous). Rule of thumb is to stay at 80% or less of a circuit's lowest-rated component, so the 16A of the larger 15k BTU unit is right on the money.

So, my analysis said that there was no problem with electricity supply, the units are physically interchangeable, use the same thermostatic control units, and the price difference is manageable (about $90). For this Texas boy that made the decision to purchase the larger one pretty easy.
It would be even more helpful if I had directly answered some of your questions.

In the case of the Dometic Brisk II 15k BTU Air Conditioner with a 16A pull - this represents a total of 44% of the output capacity of your generator. This is well within expected and safe capacity, even when coupled with other current draws like lighting and televisions. Pretty much no other concurrent draw is going to come even close to the draw of that A/C unit, so the remaining capacity in the generator should stand you in good stead. Again, the electricity demand of a 15k BTU unit vs. a 13.5k BTU unit is a very small amount of the total generator capacity.

My generator is also the Onan 4000, so for me the extra juice represents 1.9% additional load of the generator's total capacity.

Better to have and not need...
__________________
Brad Felmey
Non-Retired Full-Timer
2018 Tiffin Allegro RED 33AA
Brad Felmey is offline   Reply With Quote
Old 05-13-2016, 05:58 PM   #12
Senior Member
 
harleyjt's Avatar
 
Newmar Owners Club
Workhorse Chassis Owner
Join Date: Jan 2015
Location: Olive Branch, MS
Posts: 1,598
Size matters.


jt
2005 Newmar Kountry Star gas 3742, Workhorse 8.1L w/Allison 5 speed.

Sent from my iPhone using iRV2 - RV Forum
__________________
2005 Newmar Kountry Star Gas 3742
Workhorse W24, 8.1L/Allison 5-spd
JT, Em & the boys, Kong & Baxter (rescued grey tabbies)
harleyjt is offline   Reply With Quote
Old 05-14-2016, 08:24 AM   #13
Senior Member
 
Join Date: Jan 2015
Posts: 658
I just replaced my 13.5k rear heat pump with a 15k. My RV repair shop said the price of the 15k was $10 less than the 13.5K same brand (Coleman) and model and very little difference in current draw. Base on the current draw on my power panel the new rear 15k draws 1 amp less the my old front 13.5k. The total cost of him ordering the unit and installing it was $150 less than it would cost me for the unit.
Check the cost on line then check with a RV repair shop (not a Dealer). I was surprised how much less his cost was verses mine.
__________________

__________________
redcolorado is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Reese 15k Fifth wheel hitch question 4ms Trailer Towing and Tow Vehicles Discussion 10 07-30-2009 10:16 PM
Wheel Bearing adjustment/service at 15K, W-24 Paul T Workhorse and Chevrolet Chassis Motorhome Forum 4 10-10-2007 07:28 PM
Run 1 15K air on 20 amp? E Z Livin MH-General Discussions & Problems 4 07-06-2007 05:10 PM
13.5k btu or 15k btu air condtioning PClayton Travel Trailer Discussion 2 07-19-2005 09:17 AM
Husky 15K single pivot diandtom Trailer Towing and Tow Vehicles Discussion 10 03-12-2005 07:20 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:43 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.