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 07-07-2015, 02:51 PM   #1
Junior Member
 
Join Date: Jan 2015
Posts: 5
Blog Entries: 1
Coleman AC issue

Need help diagnosing our AC unit. The fan motor on our Coleman Mac 1500 roof ac unit intermittentaly stops running. The compressor continues to run. I have changed the capacitors and the control unit inside the air return. All wiring looks good. Checked 12volt supply from stat it remains good even when fan motor shuts down. Any suggestions what to do next?
__________________

__________________
dptadf 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 07-07-2015, 03:21 PM   #2
Senior Member
 
Lt Dan's Avatar


 
Tiffin Owners Club
Join Date: Sep 2013
Location: DFW, Texas
Posts: 1,655
Quote:
Originally Posted by dptadf View Post
Need help diagnosing our AC unit. The fan motor on our Coleman Mac 1500 roof ac unit intermittentaly stops running. The compressor continues to run. I have changed the capacitors and the control unit inside the air return. All wiring looks good. Checked 12volt supply from stat it remains good even when fan motor shuts down. Any suggestions what to do next?
Sounds like it could either be an open winding in the blower motor, or a defective fan relay. The blower runs on 120v AC, not on 12v. The 12v from the tstat is for control only and should activate a fan relay somewhere. The relay may be incorporated into the control board that you have already replaced.
__________________

__________________
Dan & Ro with two Rescued Boston "Terrorists" Jade & Jewel
2017 Phaeton 40IH Maroon Coral - Power Glide Chassis with IFS (05/17)
Previously '15 Tiffin Allegro RED 38QRA and '06 Itasca Sunrise 35A
'12 Jeep Wrangler Sport and/or '08 Honda Goldwing
Lt Dan is offline   Reply With Quote
Old 07-08-2015, 09:48 PM   #3
Senior Member
 
Jupiter's Avatar


 
Join Date: Apr 2011
Posts: 557
Lt. Dan gave you sound advice. Since it is an intermittent problem, my first two culprits would be 1) evaporator fan motor tripping on thermal overload, or 2) bad fan relay (12v/120v). If it was a low or high pressure trip the compressor would also shut down.

cheers,
Joopy
__________________
Jupiter is offline   Reply With Quote
Old 07-08-2015, 11:22 PM   #4
Member
 
Join Date: Nov 2009
Location: Ft Lauderdale, FL
Posts: 68
Had this problem 2x. Just change out the fan motor. Research the part # and buy a new motor. For my Mach 3 it cost about $150. Not that difficult to do.
__________________
Ggrvusa is offline   Reply With Quote
Old 07-08-2015, 11:25 PM   #5
Member
 
Join Date: Nov 2009
Location: Ft Lauderdale, FL
Posts: 68
Let me be more specific. My motor was sticking and hard to turn. If I accessed the hamster cage from inside the coach and gave it a few spins I could get it to work.
__________________
Ggrvusa is offline   Reply With Quote
Old 07-09-2015, 02:59 AM   #6
Senior Member
 
stink's Avatar
 
Join Date: Apr 2012
Posts: 1,414
do you have a coleman mach_ dual zone thermostat ? do you have flourecsent lights? If so on both you might have a ballast problem on one or more flourecsent lights. The defective ballasts will impart an rf signal into the 12v electrical and mess up the thermostats functions turning on or off items on its own. Mine would turn on the ac fan when you turned on the flourescent light above the kitchen or turn off the heater or anything else that you didnt choose
__________________
Dave and Laura & two cats
02 Discovery with Accord toad
retired auto rv tech and teacher, wife rt nurse
stink is offline   Reply With Quote
Old 07-09-2015, 06:42 AM   #7
Member
 
bobder41's Avatar
 
Fleetwood Owners Club
Freightliner Owners Club
Join Date: Apr 2015
Location: Ladson, SC
Posts: 76
Replace the fan motor, the bearings are sticking causing it to overheat and stop
__________________
Bob
2016 Expedition 38K
bobder41 is offline   Reply With Quote
Old 07-09-2015, 07:05 AM   #8
Senior Member
 
Join Date: Feb 2011
Location: Snowbird - Waterford Mi and Citrus Springs Fl.
Posts: 3,609
Thinking thermal overload here too. Being cheap by nature, and having more time than money (retired), I'd be tempted to get a drop or 2 of oil on those bearings if the motor seems stiff, especially if it's spent a lot of it's time sitting unused?

Worst case, you're going to have to pull the motor anyway to replace it. If access to the bearings make it difficult or impossible to oil, why not pull the motor, put a couple drops of motor oil (whatever weight oil you have handy) on each end of the motor where the shaft exits, and try it? This isn't just a patch. Many motors will go for years once this is has been done. I've had success after success with the move. If you're doing your own work it's worth a try. If you're paying somebody, maybe not so much....
__________________
1997 37' HR Endeavor, 275hp Cat, Freightliner
03 CR-V Blue Ox, Ready Brake
ahicks is offline   Reply With Quote
Old 07-09-2015, 01:25 PM   #9
Senior Member
 
lavamanz's Avatar
 
Join Date: Jul 2010
Location: central Fl
Posts: 114
Coleman AC issue

My fan would hum when the unit came on so I tried to oil my 15 year old Coleman Mach fan motor shaft & it lasted a month maybe. The shaft wasn't turning freely at all. I then replaced the fan motor & start capacitor & I was back in business.
__________________

__________________
lavamanz 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
Coleman A/C fan upgrade - 6 blade to 3 blade Jupiter Winnebago Industries Owner's Forum 48 04-02-2017 12:53 PM
2015 Ventana Cummins Engine Stalling Issue cstar5634 Cummins Engines 8 10-21-2015 09:59 PM
Slight oil leak...Issue or non Issue? Speedjester Cummins Engines 6 09-03-2015 08:17 AM
Fuel issue solved Elandan85 Class A Motorhome Discussions 4 07-07-2015 05:45 AM
Strange Electrical Issue baldtat MH-General Discussions & Problems 18 01-13-2014 07:44 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 05:54 AM.


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