|
02-17-2014, 12:41 PM
|
#1
|
Senior Member
Join Date: Dec 2012
Location: Full Timing
Posts: 751
|
Rear A/C Issue
When I turn on the air conditoners, I set the Duo-Therm Comfort Control mode to cool. I set the desired temperature for Zone 1 and Zone 2. After a couple of minutes, both A/C units start running.
About five minutes later, the rear A/C unit stops. The temperature hasn't cooled own to the desired temperature. The rear A/C doesn't restart, no matter what temperature I set Zone 2 to. The front A/C continues to cool the coach.
If I shut everything down and wait for a while, I can get the rear A/C to run again, but than it stops after a few minutes.
Any thoughts on what's going on with the rear A/C unit?
__________________
Mike
2003 Alpine Coach 40MDTS - 400HP Cummins ISL
Can Am Spyder Roadster
|
|
|
|
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!
|
02-17-2014, 01:14 PM
|
#2
|
Senior Member
Join Date: Mar 2013
Location: Fort Worth TX
Posts: 845
|
The compressor may be getting too hot and shutting itself down.
__________________
2005 Newmar Dutch Star 4024
Pulling my 2012 Malibu w/Blue OX & Patriot brake unit
|
|
|
02-17-2014, 01:22 PM
|
#3
|
Senior Member
Join Date: Dec 2012
Location: Full Timing
Posts: 751
|
I cleaned some debris from the rear temperature sensor. Then I turned the front A/C off. I set the rear thermostat to 70 degrees (it's about 80 degrees outside and 77 in the coach.
The rear A/C ran for 7 minutes then shut down. I didn't touch anything. 15 minutes later it started up and ran for 9 minutes then shut down. My IR thermometer shows the temp in the rear bedroom never got down to 70.
If there's thermal protection built into the compressor, how do I test that?
__________________
Mike
2003 Alpine Coach 40MDTS - 400HP Cummins ISL
Can Am Spyder Roadster
|
|
|
02-17-2014, 01:27 PM
|
#4
|
Senior Member
Join Date: Jan 2013
Location: Indianapolis,Indiana
Posts: 248
|
Quote:
Originally Posted by Koop
I cleaned some debris from the rear temperature sensor. Then I turned the front A/C off. I set the rear thermostat to 70 degrees (it's about 80 degrees outside and 77 in the coach.
The rear A/C ran for 7 minutes then shut down. I didn't touch anything. 15 minutes later it started up and ran for 9 minutes then shut down. My IR thermometer shows the temp in the rear bedroom never got down to 70.
If there's thermal protection built into the compressor, how do I test that?
|
With an ohm meter at the compressor terminals. I doubt if the internal overload of the compressor is tripping on you because it normally takes hours for it to reset.
__________________
John & Berenda
2014 Palazzo 33.2
KarKaddy SS / Chevy Cruze
|
|
|
02-17-2014, 03:44 PM
|
#5
|
Senior Member
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,385
|
Sounds like you changed the situation for the better cleaning the sensor. Maybe some more cleaning of the sensor (or replacement?) is in order. The sensor may be bad & distorting the temp input to tstat.
After a real thorough cleaning of sensor, if you don't get to 70, maybe you could live w/it by setting it for ~65 for the rear & it would settle ~70. How does the furnace act? I believe they use the same sensor.
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
|
|
|
02-17-2014, 04:16 PM
|
#6
|
Senior Member
Alpine Owners Club
Join Date: May 2008
Location: Ocala, FL
Posts: 260
|
Make sure the a/c is not blowing directly on the sensor.
__________________
Jim & Sandy
2008 34' FDDS Alpine
Limited SE
|
|
|
02-17-2014, 06:18 PM
|
#7
|
Senior Member
Join Date: Dec 2012
Location: Full Timing
Posts: 751
|
I did a little more digging around. I was working towards the sensor getting too cold. My IR thermometer was showing temps in the 60s at the roof air inlet in the bedroom ceiling. The sensor for the thermostat is next to the air inlet.
I removed the grill and found ducting in there that passed through the air inlet that was cold (of course, cold air was passing through the duct). What was interesting is this; there was a 2" square opening in the plywood around the air intake that the wire from the temp sensor passed through.
This opening had foam insulation, but the foam beads had deteriorated. I think this was the source of the debris I found in the sensor cover. My theory now is that air, cooled by the duct, is travelling into the sensor via this opening in the insulation.
I cut a piece of cardboard to cover the opening and duct taped it in place. We'll see tomorrow when the temperature warms if this makes any difference.
__________________
Mike
2003 Alpine Coach 40MDTS - 400HP Cummins ISL
Can Am Spyder Roadster
|
|
|
02-18-2014, 06:58 AM
|
#8
|
Senior Member
Alpine Owners Club
Join Date: Mar 2009
Location: Surprise, AZ
Posts: 836
|
Koop,
My coach is being renovated by Classic Coach Works here in Florida where they also observed that the output ducts on the rear A/C are technically mounted too close to the input duct thus causing a direct "swirl" of cold air back into the unit. I've closed the closest output duct but haven't had a chance to check the operation since it's still being renovated.
They also have an input baffle modification for the A/C units that reduce the noise and increase efficiency. We haven't been able to verify all of this since again it's still being renovated. We talked to another MH owner who claimed the noise was dramatically reduced. Sure sounds good to me! We'll be testing all of this once we get to Arizona in a couple of weeks.
__________________
Bob Bowers (Surprise, AZ)
2003 Alpine Coach 40' FDTS
2014 Jeep Cherokee Lattitude
|
|
|
02-18-2014, 07:51 AM
|
#9
|
Senior Member
Join Date: Nov 2007
Location: Charleston, WV
Posts: 3,469
|
Quote:
Originally Posted by EngineerMike
How does the furnace act? I believe they use the same sensor.
|
On mine the furnace only operates on Zone 1 so it uses the front sensor, not the bedroom one.
__________________
John and Mary Knight
2015 Newmar Ventana 4311 - wheelchair accessible
2015 Cadillac SRX Luxury AWD
|
|
|
02-18-2014, 07:53 AM
|
#10
|
Senior Member
Join Date: Nov 2007
Location: Charleston, WV
Posts: 3,469
|
Quote:
Originally Posted by bcbowers
Koop,
They also have an input baffle modification for the A/C units that reduce the noise and increase efficiency. We haven't been able to verify all of this since again it's still being renovated. We talked to another MH owner who claimed the noise was dramatically reduced. Sure sounds good to me! We'll be testing all of this once we get to Arizona in a couple of weeks.
|
Would like to know if that baffle is available for purchase.
__________________
John and Mary Knight
2015 Newmar Ventana 4311 - wheelchair accessible
2015 Cadillac SRX Luxury AWD
|
|
|
02-21-2014, 07:28 PM
|
#11
|
Senior Member
Alpine Owners Club
Join Date: Mar 2009
Location: Surprise, AZ
Posts: 836
|
We picked up our coach from having renovation work done that included the baffles on the A/C units. WOW - what a difference! I'm not sure if the noise reduction or the volume of air is better. Before the baffles, the front A/C unit would push some air back into the bathroom area but the rear A/C would barely push the air through the bathroom area. I can now feel both pushing air much further.
The baffles were uniquely designed by Classic Coach Works. They do not have a patent on them but they're only available through CCW. I assume you can order them and install them yourself. Don't have a price for them either. They don't look like a difficult DIY project.
Here's a picture of the front unit:
__________________
Bob Bowers (Surprise, AZ)
2003 Alpine Coach 40' FDTS
2014 Jeep Cherokee Lattitude
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
|