Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 

Go Back   Keystone RV Forums > Keystone Tech Forums > Technical Corner
Click Here to Login

Reply
 
Thread Tools Display Modes
 
Old 08-19-2019, 12:42 PM   #21
Andyjman
Junior Member
 
Join Date: Feb 2019
Location: San jacinto
Posts: 8
This is excellent info. I have a 2018 carbon 403, and I am looking to do the same thing. I have a max-air fan/vent in the garage, and I am looking to remove it and replace it with an A/C unit because we go to the colorado river quite often during the summer, and with our 2 A/C units, it just wouldn't stay comfortable. We dont have the power management system luckily, and I have room on my panel where there are breakers that arent used, so it shouldnt be too big of an issue to set it up. I was curious to see how many folks were able to run all 3, and I am very delighted to see that some of you have been able to.
My biggest struggle I think will be getting the power wires up to the vent. who knows, maybe Ill luck out and find one already there, but to my knowledge, the carbons didn't have the option for a third A/C.

Thank you,

Andy
Andyjman is offline   Reply With Quote
Old 08-19-2019, 02:12 PM   #22
LewisB
Senior Member
 
LewisB's Avatar
 
Join Date: Aug 2013
Location: Tucson
Posts: 822
Quote:
Originally Posted by Andyjman View Post
This is excellent info. I have a 2018 carbon 403, and I am looking to do the same thing. I have a max-air fan/vent in the garage, and I am looking to remove it and replace it with an A/C unit because we go to the colorado river quite often during the summer, and with our 2 A/C units, it just wouldn't stay comfortable. We dont have the power management system luckily, and I have room on my panel where there are breakers that arent used, so it shouldnt be too big of an issue to set it up. I was curious to see how many folks were able to run all 3, and I am very delighted to see that some of you have been able to.
My biggest struggle I think will be getting the power wires up to the vent. who knows, maybe Ill luck out and find one already there, but to my knowledge, the carbons didn't have the option for a third A/C.
Andy,
If you are starting from scratch with a third AC unit in the garage, some of the guys have added a new seperate power supply using a second power feed from the 20A breakers commonly available in an RV shore power supply. So they don't run this through the existing trailer power center. I'm not sure what they have done for a sub/box/breaker on the trailer. If you are interested, you could ask around/search for more information.

In the garage, you might have more flexibility so far as routing the power - you could, for example, maybe use "surface conduit" for the wires if you don't mind this in the garage environment. One thing to keep in mind; you will want some type of remote control for on/off and setting the temperature. Using the controls on the AC panel would mean climbing a ladder or using a step stool just to reach the unit on the garage ceiling.

Good luck with your project.
Brad
__________________
Brad & Penny (50 years!)
2017 F350 DRW CC 4x4 Payload=5560
2018 Raptor 353TS
2019 Can Am Maverick Sport XRC - the "Blue Goose"

On YouTube: https://www.youtube.com/channel/UCjc...yZ_w7jyofaPLVQ
LewisB is offline   Reply With Quote
Old 08-19-2019, 03:58 PM   #23
Andyjman
Junior Member
 
Join Date: Feb 2019
Location: San jacinto
Posts: 8
I was thinking ill either pull a t stat wire along with it and have a digital thermostat for it, or see if i can buy an expansion module and add the third unit to the zone controller that the other 2 are already on.
Andyjman is offline   Reply With Quote
Old 08-26-2020, 09:17 AM   #24
Mheathms
Junior Member
 
Join Date: Aug 2020
Location: Gautier
Posts: 2
Fuzion with added garage ac

Quote:
Originally Posted by LewisB View Post
This is an old thread, but still a current problem. We thought our 2018 trailer had the new "omni-chill" system - turns out it didn't. So we were faced with the issue of only being able to run 2 of the 3 AC units at any given time. Additionally, it would always run the main cabin + either the garage or bedroom. So when the garage is being used as a bedroom, someone is not getting AC!!!

Thanks to guidance from Racebug and others on this forum, we found an easy fix. Our trailer includes the same Precision Circuits Power Saver Switch referenced by Racebug in his post. In a 2018 Raptor 353TS, this switch was behind the fireplace just below the WFCO power center. The switch is a "dumb" switch - that is it requires NO external controls. If it senses current in the "primary" circuit (in our case the bedroom AC), it will not allow current in the "secondary" circuit (in our case the garage AC). If current is 0 in the primary, then the secondary can get line power. I've included the documentation and wiring diagram for this switch in this post.

Simple fix (for us): Lift off the faceplate of the fireplace and remove 4 screws for fireplace; set fireplace to the side and remove 2 screws for power saver switch cover. I removed the "secondary" wires from this switch and routed the wires into the WFCO power center just above it. I didn't have to cut or lengthen any wires. I hooked the garage AC wire up to share the 20A circuit for the washer/dryer area in the garage. We don't plan to ever install a washer; but if we do, it would mean that we would need to shut off the AC in the garage before we started the washer.

No other modifications were necessary. All 3 AC units now run including running them with the 5500 watt generator - my guess is that you couldn't run much else on the generator when you do this. You might want to shut off the breaker for the converter to delay any battery charging - in our case, the solar system keeps the batteries topped off so there is little demand on the converter. Make sure the fridge is on propane to minimize demand to only that necessary for the DC controls.

Wow - we ran 3 units for about an hour in Tucson when it was nearly 100 degrees and we could immediately tell how much better the AC system performed. This is the best modification I could ever make to an already great trailer.

Attachment 22633
Attachment 22634

Hope this might help someone else - it's Worth it IMO.
we added a 3rd roof ac in garage but it is not connected to other acs. Haven’t tried all three
Mheathms is offline   Reply With Quote
Old 08-26-2020, 03:18 PM   #25
wiredgeorge
Senior Member
 
wiredgeorge's Avatar
 
Join Date: Nov 2017
Location: Mico, TX
Posts: 7,392
Quote:
Originally Posted by Mheathms View Post
we added a 3rd roof ac in garage but it is not connected to other acs. Haven’t tried all three

I suspect that OEMs have systems where two of three A/C units can run at any one time for a reason. I think your 50A service may not be up to the task unless your camper was originally wired to accommodate three A/Cs and then only two can be selected or the two will shuttle automatically but I don't think three will run at once.
__________________
wiredgeorge Mico TX
2006 F350 CC 4WD 6.0L
2002 Keystone Cougar 278
2006 GL1800 Roadsmith Trike
wiredgeorge is offline   Reply With Quote
Old 08-28-2020, 04:35 AM   #26
Mheathms
Junior Member
 
Join Date: Aug 2020
Location: Gautier
Posts: 2
I sorta figured I couldn’t run all three, but I read where some people did.
Mheathms is offline   Reply With Quote
Old 08-28-2020, 05:29 AM   #27
flybouy
Site Team
 
Join Date: Oct 2011
Location: Joppa, MD
Posts: 11,714
Quote:
Originally Posted by LewisB View Post
Andy,
If you are starting from scratch with a third AC unit in the garage, some of the guys have added a new seperate power supply using a second power feed from the 20A breakers commonly available in an RV shore power supply. So they don't run this through the existing trailer power center. I'm not sure what they have done for a sub/box/breaker on the trailer. If you are interested, you could ask around/search for more information.

In the garage, you might have more flexibility so far as routing the power - you could, for example, maybe use "surface conduit" for the wires if you don't mind this in the garage environment. One thing to keep in mind; you will want some type of remote control for on/off and setting the temperature. Using the controls on the AC panel would mean climbing a ladder or using a step stool just to reach the unit on the garage ceiling.

Good luck with your project.
Brad
If you can run a unit from the 20 amp outlet, then why couldn't you run 2 units off the 50 Amp service? Seems to me that if the two units are pretty much the only load on that line and the other major loads like microwave, water heater and fridge are on the other 50 Amp line (like every 30 amp trailer) it should be ok.
__________________
Marshall
2012 Laredo 303 TG
2010 F250 LT Super Cab, long bed, 4X4, 6.4 Turbo Diesel
flybouy is offline   Reply With Quote
Old 06-09-2021, 09:11 AM   #28
DesertCoyote
Junior Member
 
DesertCoyote's Avatar
 
Join Date: Jun 2021
Location: Queen Creek
Posts: 17
Hey all - just got my new 2021 Raptor 415 - Has 3 ACs and same issue - does anyone know the locations of this so called smart controller and what I need to do to disable it - to allow the garage AC to come on? Living in AZ, this is a must to have all 3 running at once..

Thanks!
DesertCoyote is offline   Reply With Quote
Old 06-09-2021, 09:19 AM   #29
K_N_L
Senior Member
 
Join Date: Apr 2017
Location: Lanexa
Posts: 260
Quote:
Originally Posted by DesertCoyote View Post
Hey all - just got my new 2021 Raptor 415 - Has 3 ACs and same issue - does anyone know the locations of this so called smart controller and what I need to do to disable it - to allow the garage AC to come on? Living in AZ, this is a must to have all 3 running at once..

Thanks!
In general it will be very close to your power distribution center as the power home runs will all terminate there. In my case (distro box is under the fridge cabinet) it was accessible from the adjacent lower kitchen drawer. I did have to remove the pwr dist box to route the 3rd ac feed into my new breaker. Some poking around will be needed unless someone with the same unit can add more info.

In short, I removed the 3rd ac feed from the load sharing unit and ran it directly to a new breaker, leaving the unit inline on the 2nd unit. My new breaker is on the same side of the panel as the fireplace and the washer / dryer circuits (which I dont have) to keep the load happy.
__________________

Kevin -n- Lisa
17 Fuzion 325 / 15 Chevy 3500 HC DRW
06 HD Ultra Classic
K_N_L is offline   Reply With Quote
Old 06-09-2021, 09:23 AM   #30
DesertCoyote
Junior Member
 
DesertCoyote's Avatar
 
Join Date: Jun 2021
Location: Queen Creek
Posts: 17
Thanks K_N_L - I'll start digging there - mine is located under the sink..
DesertCoyote is offline   Reply With Quote
Old 06-09-2021, 09:53 AM   #31
LewisB
Senior Member
 
LewisB's Avatar
 
Join Date: Aug 2013
Location: Tucson
Posts: 822
Quote:
Originally Posted by K_N_L View Post
In general it will be very close to your power distribution center as the power home runs will all terminate there. In my case (distro box is under the fridge cabinet) it was accessible from the adjacent lower kitchen drawer. I did have to remove the pwr dist box to route the 3rd ac feed into my new breaker. Some poking around will be needed unless someone with the same unit can add more info.

In short, I removed the 3rd ac feed from the load sharing unit and ran it directly to a new breaker, leaving the unit inline on the 2nd unit. My new breaker is on the same side of the panel as the fireplace and the washer / dryer circuits (which I dont have) to keep the load happy.
You absolutely CAN run all 3 AC units from a 50A service by doing this. It is a wonderful modification!

Here's the power-share switch info. Ours was behind the WFCO power center under the TV cabinet. It is basically just a "dumb" switch that says if power is on for A, then it is off for B and vice versa. It doesn't run or cycle based on sensing temperatures or other "smart" function. So if both units want to be ON based on temperature, it will take some other "smart" device to cycle the two units back and forth.
00-10031-000-Power-Share-Switch-RevA.pdf

Only 1 precaution: I would only run all 3 AC units on shore power through an EMS. Running all 3 units on your 5500W Onan/Cummins generator will work, but it is very likely that you will put your generator at risk from excessive operating temperatures running it at near max output, inside a compartment, at the hottest part of the day. Don't forget your generator is de-rated by both ambient temperature (over 70°) and MSL elevation (over sea level) operation. Three AC units at higher elevation on a very hot day could cause very high current and lower voltages on your AC units. JMHO
__________________
Brad & Penny (50 years!)
2017 F350 DRW CC 4x4 Payload=5560
2018 Raptor 353TS
2019 Can Am Maverick Sport XRC - the "Blue Goose"

On YouTube: https://www.youtube.com/channel/UCjc...yZ_w7jyofaPLVQ
LewisB is offline   Reply With Quote
Old 06-09-2021, 10:01 AM   #32
DesertCoyote
Junior Member
 
DesertCoyote's Avatar
 
Join Date: Jun 2021
Location: Queen Creek
Posts: 17
Thanks for info - I'll post up what I find for the location of this.. will really be nice to have 3 A/Cs going for the fun AZ summer...
__________________
Lloyd & Jennifer
-2021 Raptor 415
-2019 Ford F350 6.7 CC Dually
DesertCoyote is offline   Reply With Quote
Old 06-18-2021, 11:03 AM   #33
DesertCoyote
Junior Member
 
DesertCoyote's Avatar
 
Join Date: Jun 2021
Location: Queen Creek
Posts: 17
Update: I did find this little "box" located under the sink in the new 21 raptors. Did some rewiring and put the run for the 3rd AC into the Washer breaker - it was also a 20 amp breaker so thought it should all be OK.

Fired up Genny and sure enough, got all 3 A/Cs to start and run - but the joy only lasted for about 5 mins, then one of the 30amp breakers flipped directly on the gen. Odd, it was running all 3 easily, so I assume a 5500 can push enough wattage, but why did a breaker flip on it?? Haven't tried the whole setup on 50-amp shore power yet (need to do that once at an RV park as I don't have a 50-amp shore at home yet).
__________________
Lloyd & Jennifer
-2021 Raptor 415
-2019 Ford F350 6.7 CC Dually
DesertCoyote is offline   Reply With Quote
Old 06-18-2021, 11:47 AM   #34
JRTJH
Site Team
 
JRTJH's Avatar
 
Join Date: Mar 2011
Location: Gaylord
Posts: 26,837
Quote:
Originally Posted by DesertCoyote View Post
Update: I did find this little "box" located under the sink in the new 21 raptors. Did some rewiring and put the run for the 3rd AC into the Washer breaker - it was also a 20 amp breaker so thought it should all be OK.

Fired up Genny and sure enough, got all 3 A/Cs to start and run - but the joy only lasted for about 5 mins, then one of the 30amp breakers flipped directly on the gen. Odd, it was running all 3 easily, so I assume a 5500 can push enough wattage, but why did a breaker flip on it?? Haven't tried the whole setup on 50-amp shore power yet (need to do that once at an RV park as I don't have a 50-amp shore at home yet).
The specifications for Dometic 13.5 BTU A/C's calls for 3.5KW for one unit and 5KW for two units. Dometic does not specify power requirements for 3 or more units, but I'd guess it's probably the same 1.5KW additional power. If so, that would call for the following:

1 A/C 3500 watts
2 A/C 5000 watts
3 A/C 6500 watts
4 A/C 8000 watts.

As an air conditioner runs, the refrigerant pressure builds and the compressor has to work harder to compress that pressure. The "head pressure to initially start the compressor" can "almost be a direct short" requiring 50-75 amps to get the compressor moving. There is a capacitor system to assist startup, but if you have one air conditioner running and two trying to start or even if you have two running and one trying to start on a very hot day, you may be "pulling significantly more than 5500 watts from your generator. When you look at the schematic for your generator, you'll find a 30 amp breaker protecting one side of the circuit. 120 volts x 30 amps is 3600 watts... That's 1400 watts less than the Dometic requirement for two air conditioners (5KW) so trying to run three would significantly overload the generator 30 amp breakers when all three are trying to run at the same time and "cycling on/off" simultaneously.

Remember, your 50 amp trailer provides 12,000 watts. That's broken down to two legs of 6000 watts each, so your 5500 watt generator is only providing less than half of one leg of your normal power input..... That's a SIGNIFICANT power reduction to try to run three air conditioners plus the power center converter and other equipment.
__________________
John



2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS
JRTJH is online now   Reply With Quote
Old 07-28-2021, 10:26 AM   #35
CGramer
Junior Member
 
Join Date: Jul 2021
Location: Weatherford
Posts: 1
3rd AC install

I am going to try the soft start route. I am going to put two AC units on one pole of my Voltage 3551 with soft starts and another unit on the other side with the fridge, microwave, etc. Some great information on this post. Maybe I can take some pictures of my progress.
CGramer is offline   Reply With Quote
Old 07-06-2022, 07:50 AM   #36
Kevin8520
Junior Member
 
Join Date: Apr 2022
Location: Buena Park
Posts: 16
I try not to resurrect old threads, but I'm having a heck of a time finding said power management box. I have two zones running off a single 20 amp breaker in my panel and they will not run simultaneously, so I'm sure I have the load management switch discussed in this thread. I've pulled the fireplace out and still don't see the box. Does anyone know where else to look on a 2016 Raptor 425TS?
__________________
2016 Keystone Raptor 425TS
2021 GMC Sierra Denali HD
Kevin8520 is offline   Reply With Quote
Old 07-09-2022, 08:13 PM   #37
Kevin8520
Junior Member
 
Join Date: Apr 2022
Location: Buena Park
Posts: 16
Quote:
Originally Posted by Kevin8520 View Post
I try not to resurrect old threads, but I'm having a heck of a time finding said power management box. I have two zones running off a single 20 amp breaker in my panel and they will not run simultaneously, so I'm sure I have the load management switch discussed in this thread. I've pulled the fireplace out and still don't see the box. Does anyone know where else to look on a 2016 Raptor 425TS?
Answered my own question. The power management box is directly behind the panel. Remove the 4 screws and pull the panel out, remove the romex from the power management box and stuff them into the panel. I had to replace one full size 20 amp breaker with a single pole dual output 20 amp slim breaker type QT.
Attached Thumbnails
Click image for larger version

Name:	EFDC095B-B6FA-43C3-864A-486790A4FE9B.jpg
Views:	132
Size:	181.0 KB
ID:	40645  
__________________
2016 Keystone Raptor 425TS
2021 GMC Sierra Denali HD
Kevin8520 is offline   Reply With Quote
Old 05-30-2023, 01:52 PM   #38
NavyDOC
Junior Member
 
Join Date: May 2023
Location: South Jordan
Posts: 1
looking for the A/C power share

Quote:
Originally Posted by Racebug View Post
Found it. Wired one to the breaker and tied the other into the washer\dryer circuit since I don't plan on having a washer or dryer.

Sent from my VS988 using Tapatalk
I know this thread is a few years old, but I want the A/C power share box on my 2017 Fuzion 417. Like most in this post, I do not plan to use the washer/dryer and would like to wire the 3rd a/c to this circuit. I have looked behind the fireplace, under the fridge, under the stove, and the space under the sink with no luck.
NavyDOC is offline   Reply With Quote
Old 05-30-2023, 02:06 PM   #39
Kevin8520
Junior Member
 
Join Date: Apr 2022
Location: Buena Park
Posts: 16
Quote:
Originally Posted by NavyDOC View Post
I know this thread is a few years old, but I want the A/C power share box on my 2017 Fuzion 417. Like most in this post, I do not plan to use the washer/dryer and would like to wire the 3rd a/c to this circuit. I have looked behind the fireplace, under the fridge, under the stove, and the space under the sink with no luck.



I have a 2016 Raptor 425. I think the build is similar to your 417. My box was BEHIND the breaker panel. I removed the 4 screws and pulled the breaker panel out and the load balancing box was screwed to the wall behind it.


Also, see my attached photo.
Attached Thumbnails
Click image for larger version

Name:	panel.jpg
Views:	137
Size:	174.9 KB
ID:	44064  
__________________
2016 Keystone Raptor 425TS
2021 GMC Sierra Denali HD
Kevin8520 is offline   Reply With Quote
Reply

Tags
air conditioner

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
Forum Jump

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by the Keystone RV Company or any of its affiliates in any way. Keystone RV® is a registered trademark of the Keystone RV Company.


All times are GMT -8. The time now is 06:49 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.