Go Back   iRV2 Forums > RV SYSTEMS AND TECHNOLOGIES FORUMS > RV Systems & Appliances
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 04-01-2012, 03:52 PM   #1
Junior Member
 
Join Date: Apr 2012
Posts: 1
Roof top AC compressor kicks on, runs for 3 seconds then kicks off

I have a 2000 model 5th wheel that has a roof top air conditioner, I believe its a coleman mach 3 (I cant find a model for it anywhere, the thermostat just says "Coleman Mach" and looking at pictures of other mach 3 units, it looks just like mine). The fan will blow air just fine and appears to be working perfectly, but the compressor will not stay running. When I change the thermostat to cool, the compressor will either kick on or try to kick on and run for about 3 seconds then quit. 25-30 seconds later it will kick on/try to kick on, run for about 3 seconds and quit.

When I first tried it a few weeks ago, the compressor wouldn't even try to kick on at all, but I replaced the start capacitor and that made it actually kick on and run the way it is now. I have also replaced the run capacitor but that didn't change anything. I've checked the voltage running to the roof unit and it never drops below 120-122 volts. A few weeks ago I also checked the voltage running to the compressor when it tries to kick on, I forget the exact voltages running to it, but I think the lead from the run capacitor was dropping to like 50v (I'll check again if this should be looked into).

Is there anything else that I can try? The only other things I've come up with are getting a new potential start relay or getting a 'super boost' to get the compressor going.
__________________

__________________
Steven2k7 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 04-01-2012, 04:05 PM   #2
Junior Member
 
Join Date: Nov 2011
Location: Mass
Posts: 22
Perhaps it needs to be recharged
__________________

__________________
davidjb is offline   Reply With Quote
Old 04-01-2012, 06:01 PM   #3
Moderator Emeritus
 
TXiceman's Avatar


 
Vintage RV Owners Club
Texas Boomers Club
Oklahoma Boomers Club
Ford Super Duty Owner
Join Date: Aug 2000
Location: Full Time, TX Home Base
Posts: 16,629
Blog Entries: 20
Recharge is the least likely issue. You need to do some trouble shooting and see what is the item that is cycling the compressor off. There is a Klixon (thermal element ) mounted on the compressor. If the compressor is drawing excess current it will trip the Klixon and when it cools it will let the compressor start until the element get hot again.

Also, using a clamp-on amp meter, check the compressor amps when running. Also check the voltage at the A/C unit.

You will have two sets of current on the data plate. One for the whole unit and one fro the compressor only. You need to make sure you are measuring the correct current.

Ken
__________________
Amateur Radio Operator (KE5DFR)|Full-Time! 2012 Cameo 37RSQ - 2012 6.7L Ford Crew Cab Dually - Travel with one Miniature Schnauzer, one Standard Schnauzer and one small Timneh African Gray Parrot
TXiceman is offline   Reply With Quote
Old 04-01-2012, 08:45 PM   #4
Junior Member
 
Join Date: Feb 2012
Posts: 18
Automotive and home AC systems behave like that when the freon is low. I have zero experience with RV AC units, but if they're anything like the others, using a manifold guage set to check the freon level is super easy.
__________________
RustyF is offline   Reply With Quote
Old 04-02-2012, 04:34 AM   #5
Community Moderator
 
RV Wizard's Avatar


 
Country Coach Owners Club
Appalachian Campers
Gulf Streamers Club
Join Date: Mar 2000
Location: Chattanooga, Tn.
Posts: 9,830
Use a clamp on amp meter to determine the amperage of start up (or attempt). If you see something like 75 amps you may have locked rotor. You can also check running amperage and see if the klixon is the problem (tripping out under it rating), Good luck, stay safe and keep us posted.
__________________
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 350 ISC w/ Banks = 450Hp & 1330# torque
06 Saturn Vue & 06 Chevy Z71 4x4 toads
RV Wizard is offline   Reply With Quote
Old 04-02-2012, 08:47 AM   #6
Senior Member
 
Join Date: May 2009
Location: Bluff Dale, TX
Posts: 565
RV air conditioners have no refrigerant connections for the high and low side. There is no way to connect gauges to check the system.
A good AC technician can cut into the system and add ports to install freon if the problem is due to a freon leak that can be repaired.
__________________
Most RV batteries live a long and useful life, some are murdered.
2000 National Sea Breeze F53
1998 CRV Toad
garym114 is offline   Reply With Quote
Old 04-02-2012, 08:54 AM   #7
Senior Member
 
Damon Owners Club
Workhorse Chassis Owner
Join Date: Mar 2009
Posts: 13,959
I will add one other possible issue, the compressor could be partially siezed, overheating dn doing the thermal cut out thing when it starts,, This may be due to a bad start capacitor but is more likely due to an internal issue and will require replacement of the unit.. Just so you are prepared.

But the other folks may be right too, That would, in fact, be my first suspect. (THat they are right) I'm just giveing you worst case.
__________________

__________________
Home is where I park it!
wa8yxm is offline   Reply With Quote
Reply

Tags
compressor, roof



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
Renovations on our Sea View jclarkfork National RV Owner's Forum 46 09-22-2012 09:44 AM
Should I use deoxidizer on fiberglass roof??or just wax it??? tipaulfla Class A Motorhome Discussions 7 04-07-2012 06:24 PM
Brake lights on on 1999 tropi-cal 34' don't work. smilingecko Class A Motorhome Discussions 5 04-02-2012 02:52 PM
Uses for Duct Tape okmunky iRV2.com General Discussion 60 04-01-2012 10:49 PM
Q for the engineers, F-700 light leaf spring mods ok? Mekanic Truck Conversions 7 04-01-2012 03:36 PM

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

RV & Travel Trailer Communities

Our RV & Travel Trailer sites encompasses virtually all types of Recreational Vehicles, from brand-specific to general RV communities.

» More about our RV Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002-2012 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:30 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2014, vBulletin Solutions, Inc.