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

Click Here to Login
View Single Post
Old 05-30-2019, 03:55 PM   #12
javelin
Senior Member
 
Brand: Thor Motor Coach
Model: 2013 ACE 30.1
State: Alberta
Posts: 1,410
THOR #2631
Back from the dog park.....
Well your video is for a house furnace but the limit switch safety function is basically the same as for an RV furnace. If the furnace overheats the limit switch opens its contacts (high resistance). The limit switch is normally zero ohms across its two terminals unless it has tripped open on over heat, or just failed open circuit (high resistance).


Using your ohm meter function on the multimeter is probably the easiest to do. Turn off your furnace so no 12vdc is on the circuits. Switch multimeter on to ohms and touch your meter probes together......you should see zero ohms on the meter. Some analog meters have a zeroing control that allows you to manually zero the reading; digital meters usually show zero right off or there may be a zeroing pushbutton. The main thing is with probe tips touching you should see zero or close to zero ohms. Then touch the probes onto the limit switch terminals.....or the appropriate wires coming from the limit switch if it is buried in the furnace. You should see the same zero or very low resistance value as when you tested the meter probes initially. If the limit switch is high resistance it will need replacement. You will need your furnace make and model number to buy a new limit switch. After replacing the limit switch monitor your furnace and if the new limit switch fails or trips open again then you will need to check air flow through the combustion chamber and also all output heat vents in the coach to make sure there are no blockages. I hope that helps.


By the way I "don't" recommend bypassing the limit switch with a patch cord other than to verify the furnace will start again. People typically leave the bypass jumper in place and then forget about it and wonder why their coach burned up. Limit switches can fail for no particular reason as well but you need to make sure its not from actual overheating.....without checking into it.
__________________
javelin is offline   Reply With Quote
 
» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Thor Industries or any of its affiliates. This is an independent, unofficial site.




All times are GMT. The time now is 09:03 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2024, vBulletin Solutions, Inc.