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


Reply
 
Thread Tools Display Modes
Old 05-18-2014, 10:14 PM   #1
Member
 
Sabre_Ray's Avatar
 
Join Date: Dec 2012
Posts: 31
3rd A/C in unders 2 years from new?

We bought our camper in fall of 2012 (brand new) and by the summer of 2013 I had to have the Dometic roof-top unit replaced (under warranty) because it wasnt cooling any longer. The unit had good, strong air flow, the compressor DID kick on and there was no icing. The "cool" air was only marginally cooler than the return air, maybe 1-2 degrees. Brought it to the nearest authorized Dometic dealer/center, they did all the tests, captured the supply/return air temps etc, etc. and Dometic recommended the full replacement. Got the camper home, ran the air, had nice "frigid" air out of the vents just like when it was first new.

Here we are not even 1 year later and I am back to the same cooling problems and possibly looking at the third A/C unit on this camper and it isnt 2 years old yet.

The camper that I owned before this one also had a Dometic unit on it and it was just as cold the day I sold it, as it was the day I bought it, which was a period of 6 years.

Can someone please tell me what the heck is going on, LOL.
__________________
Ray, Christi and the kids
2013 Sabre Silhouette 291 BHTS

Sabre_Ray is offline   Reply With Quote
Old 05-18-2014, 10:56 PM   #2
Senior Member
 
Iwannacamp's Avatar
 
Join Date: Aug 2013
Posts: 7,916
Can you get a picture of the unit on the roof without a lot of trouble. It sounds like an airflow problem. Most likely Condensor air. Maybe something is too close to the discharge air....just a thought.
__________________
2017 Puma 297RLSS
2005 Ram 2500 4X4 diesel SMOKER!!
I love puns, irony and tasteless jokes...
born in Texas.... live in Arkansas
Iwannacamp is offline   Reply With Quote
Old 05-19-2014, 12:33 AM   #3
Senior Member
 
SKnight's Avatar
 
Join Date: Feb 2014
Posts: 1,428
It needs it's supply voltage checked while under a load. It might show 120 when off, but should maintain that value while running also. A poor connection will have it running at lower voltage which will slowly burn out the motor for the compressor. It will work fine new, but will get slower as the compressor motor gives up.

This can't be checked at the outlets, it needs to be checked at the compressor itself while running.
__________________
Now-2014 Sierra 346RETS 5er BUB
Then-2002 Keystone Springdale 286RLDS TT

Nights camped in 2014-28, 2015-127, 2016-10
SKnight is offline   Reply With Quote
Old 05-19-2014, 04:17 AM   #4
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
Could very well be electrical Or it getting leaks in it from vibration or something. They don't check for leaks anymore they just throw them away. That could get pretty expensive that's kinda unusual to keep happening. It's like anything else anymore things are being made cheaper. If it happens again tell them you want a coleman mach unit installed instead. Hope you aren't paying for this besides the time lost taking to a dealer. I would also make sure they start you warranty over on the A/C from the day they put the new one on.
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 05-19-2014, 06:10 AM   #5
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 23,268
If you run the AC with an extension cord not rated for at least 30 amps you can burn up the compressor in very short order if the input power is low to start with.

One AC being bad is misfortune, three being bad is an external issue.

Continuous monitoring of AC voltage is your next step. Any voltage reading below 105 volts during compressor start up will burn up the compressor in short order. An extension cord will make the voltage loss much worse depending on length.

I have seen 105 volts and even less at even RESORT grade campgrounds.

If you frequent campgrounds with fluctuating power levels, or use an extension cord with AC, an auto-transformer like the Franks Voltage Conditioner may be in your future.
Attached Thumbnails
Click image for larger version

Name:	Voltage Loss Per Foot of Run based on amp load.jpg
Views:	144
Size:	57.7 KB
ID:	52751   Click image for larger version

Name:	DSCF1066.jpg
Views:	170
Size:	62.2 KB
ID:	52752   Click image for larger version

Name:	DSCF1070.jpg
Views:	136
Size:	64.4 KB
ID:	52753   Click image for larger version

Name:	DSCF1069.jpg
Views:	128
Size:	62.0 KB
ID:	52754   Click image for larger version

Name:	DSCF1149.jpg
Views:	156
Size:	61.5 KB
ID:	52755  

Click image for larger version

Name:	DSCF1067.jpg
Views:	137
Size:	64.9 KB
ID:	52756  
__________________
Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
Herk7769 is offline   Reply With Quote
Old 05-19-2014, 09:00 AM   #6
Member
 
Sabre_Ray's Avatar
 
Join Date: Dec 2012
Posts: 31
Thanks...

So, first thing, (for purpose of discussing potential voltage drop) at home I have a dedicated 30amp circuit that is probably 20-30 ft from panel to receptacle, with a 25ft 30amp extension, plus the camper's ~15ft cord - total of not more than 70 ft of extension.

Question, if the compressor is burnt, will it continue to run and sound "normal"?
__________________
Ray, Christi and the kids
2013 Sabre Silhouette 291 BHTS

Sabre_Ray is offline   Reply With Quote
Old 05-19-2014, 09:02 AM   #7
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 23,268
Quote:
Originally Posted by Sabre_Ray View Post
Question, if the compressor is burnt, will it continue to run and sound "normal"?
Are you sure you are hearing the compressor and not the fan motor?
__________________
Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
Herk7769 is offline   Reply With Quote
Old 05-19-2014, 09:03 AM   #8
Senior Member
 
Iwannacamp's Avatar
 
Join Date: Aug 2013
Posts: 7,916
Good question. The "normal" sound is "normally" the fan. I don't really hear my compressor cause the fan is do loud. If the compressor is running or not running may not be obvious.
__________________
2017 Puma 297RLSS
2005 Ram 2500 4X4 diesel SMOKER!!
I love puns, irony and tasteless jokes...
born in Texas.... live in Arkansas
Iwannacamp is offline   Reply With Quote
Old 05-19-2014, 09:06 AM   #9
Senior Member
 
Iwannacamp's Avatar
 
Join Date: Aug 2013
Posts: 7,916
IMHO. Unless you got a "bad run" of a/c units...and you happened to get all that run...I would be looking at air flow or voltage. About the only thing to cause these problems.
__________________
2017 Puma 297RLSS
2005 Ram 2500 4X4 diesel SMOKER!!
I love puns, irony and tasteless jokes...
born in Texas.... live in Arkansas
Iwannacamp is offline   Reply With Quote
Old 05-19-2014, 09:06 AM   #10
Member
 
Sabre_Ray's Avatar
 
Join Date: Dec 2012
Posts: 31
Whether you're standing outside, on the roof or even inside, if you know what you're listening for you can distinctly hear the compressor kick in, few seconds after unit comes on.
__________________
Ray, Christi and the kids
2013 Sabre Silhouette 291 BHTS

Sabre_Ray is offline   Reply With Quote
Old 05-19-2014, 09:09 AM   #11
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
Quote:
Originally Posted by Sabre_Ray View Post
Thanks...

So, first thing, (for purpose of discussing potential voltage drop) at home I have a dedicated 30amp circuit that is probably 20-30 ft from panel to receptacle, with a 25ft 30amp extension, plus the camper's ~15ft cord - total of not more than 70 ft of extension.

Question, if the compressor is burnt, will it continue to run and sound "normal"?
Yes it will sound the same until the winding is burnt up. The compressor has a plus 10% or minus 10% so if you are running 120V you are safe until you drop to 108 volts. That's why progressive and TRC have a trip rate at 108 low side and 132 high side it would shut your unit off. Your 30 amp cord is #8 copper, so you would have to look up what it will carry at 70' Remember your compressor pulls 11 to 12.5 amps only plus add 1.5 amps for the fan motor at full load. I'll look up a wire chart and get back to you.
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 05-19-2014, 09:34 AM   #12
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
Attached you will find the size of wire for 70'. What size wire do they have running from the beaker to the unit? At home your 30 amp is fine with what I inputed in the cals/
Attached Files
File Type: pdf 8 copper.pdf (512.8 KB, 20 views)
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 05-19-2014, 09:59 AM   #13
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
You need to check the delta T, that is the temp. coming out of the vent and the temp. going into the return air. You might not hear the compressor running after it starts but no matter how loud your fan is you will still hear it on start-up.
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 06-07-2014, 01:47 PM   #14
Member
 
Sabre_Ray's Avatar
 
Join Date: Dec 2012
Posts: 31
Just got the camper back yesterday, the AC unit was replaced (under warranty) for the second time. Dealer did all of the usual checks, temp measurements, etc.
__________________
Ray, Christi and the kids
2013 Sabre Silhouette 291 BHTS

Sabre_Ray is offline   Reply With Quote
Old 06-07-2014, 04:13 PM   #15
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
Quote:
Originally Posted by Sabre_Ray View Post
Just got the camper back yesterday, the AC unit was replaced (under warranty) for the second time. Dealer did all of the usual checks, temp measurements, etc.
they are missing something if you are on the 2nd A/C already. Don't trust your dealer, I would get a list from either Coleman or dometic which ever unit you have. I would have them check it. No matter what they tell you there is a problem some where. But's that just IMO...
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 07-24-2014, 08:44 PM   #16
Texas
 
Join Date: Apr 2013
Location: Del Rio, TX
Posts: 26
I had to have my 6 month old Dometic replaced as well, my compressor would only run for a short time - so the delta T did not get any wider than 5 deg. The dealer checked it and found amp draw around 5.3 to 6.4 amps and only a 2 deg. delta T.. Well Dometic replaced the complete unit.. Now that new a/c is 8 months old - has a 25 deg. Delta T in High Cooling Mode - and doesn't cool any colder than 15 deg. cooler than outdoor temp.. Might have air flow issue... Back to dealer to check it - maybe just need to go ahead and add that 2nd unit to the MB - BTW we have the Crusader 295RST..
830hvacman is offline   Reply With Quote
Reply

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

Disclaimer:

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 07:03 PM.