Furnace Issue January 31, 2017, 07:01:35 pm So there I was re-winterizing, sometime I do a few times a year, when the furnace come on. I know when I last used the furnace I pushed the temperature level till I heard the click. Question - can this level have broken contacts or get dirty? If so when is the repair issues?Thank for any information......
Re: Furnace Issue Reply #1 – January 31, 2017, 07:31:22 pm The older mechanical thermostats definitely can have dirty or oxidized contacts. If you have some emery cloth or fine (600+ grit) sandpaper handy, slip a piece between the contacts and give 'em a quick cleaning.
Re: Furnace Issue Reply #2 – February 01, 2017, 09:11:00 am Along the same lines as Andy, if the thermostat is the issue, the anticipator wire in some thermostats sinks into the plastic crating a poor connection. I just moved the anticipator bar a little to the un-connected end and contact was restored.
Re: Furnace Issue Reply #3 – February 01, 2017, 09:52:24 am If the contacts were dirty or oxidized, I would expect the furnace would not turn on when it should.Was the coach warmer than expected when you got in? Any reason to think the heat has been running since your last visit at the minimum setting? If the lever was all the way OFF, you moving around in the coach may have caused the furnace to come on. Depending on the type, you may be able to remove the cover on the thermostat and look to see if the contacts have become loose or broken, allowing them to touch when they shouldn't. Another possibility is the two wires that go to\from the thermostat have chaffed bare somewhere (on mine right in the thermostat seems like the most likely place), and again, you working in the RV may have been enough to cause them to touch, completing the circuit to start the furnace. Hope this helps!
Re: Furnace Issue Reply #4 – February 01, 2017, 10:40:25 am When the thermostat in our Lance camper started turning the furnace on while in storage, I took it apart, cleaned it and tried to fix it. The problem with that thermostat was that even when the switch was in the OFF position, it would not turn de-energize the thermostat and when it got cold, the furnace would come on. When disassembly and contact cleaning didn't work, I found that a direct replacement only cost $15 and was an exact duplicate, right down to the wires and screw holes into the wall. Problem solved and it worked flawlessly. Very simple solution:Amazon.com: Atwood 38453 Thermostat: Automotive As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Furnace Issue Reply #5 – February 01, 2017, 10:48:25 am In the Hilo trailer I recently sold, I replaced the original Atwood mechanical thermostat with a digital one I found at a thrift store. 3 bucks and worked like a charm! 1 Likes
Re: Furnace Issue Reply #6 – February 01, 2017, 11:41:56 am Here is a photo of the original Atwood thermostat and the "thrift store" replacement. The Honeywell had both heat and cooling functions but I only used the heat since the AC was a non-ducted roof version.
Re: Furnace Issue Reply #7 – February 01, 2017, 04:46:34 pm On follow up ----- this morning I pulled the cover. This is a picture of what I found. Seems the lever to adjust the temperature has a tab that when pushed/pulled to the left (as you are looking at it) opens the circuit. I'm guessing that the tab has worn down a tad keeping the spring switch from opening. I pull the spring switch out a bit - seems to have fix the problem. My confidence in this thermostat is not in the high range. As I keep 'Baxter' in my driveway I'm thinking I'll pull the fuse till I'm sure the problem is solve.
Re: Furnace Issue Reply #8 – February 01, 2017, 06:29:55 pm "Seems the lever to adjust the temperature has a tab that when pushed/pulled to the left (as you are looking at it) opens the circuit."Yes, when the lever is pulled all the way to the left, a triangular plastic tab (see attached photo) separates those two contacts and prevents the furnace from operating. That's a positive shutoff--and it's a second set of contacts to clean, if and when the thermostat fails to operate. (The main thermostat contacts are inside that translucent plastic box near the bottom of the photo.)But if I understood correctly, your situation was that the furnace came on unexpectedly. Unless that triangular plastic tab is completely broken off, it's very unlikely that if that lever was pulled all the way to the left, the contacts indicated in your photo could touch--and if they don't touch, the furnace can't come on, period.So if the triangular tab is intact, then my guess is that you didn't quite pull the lever all the way to the left the last time you shut off the furnace. Yes, I know you said you heard a click, but that was probably the main contacts opening. The unexpected-startup symptoms you describe exactly match those of a thermostat that's been left on at a very low setting, instead of being turned off. I know I've done that a few times, only to be awakened in the early morning hours as the furnace unexpectedly turns on.
Re: Furnace Issue Reply #9 – February 01, 2017, 06:42:00 pm Quote from: Andy Baird - February 01, 2017, 06:29:55 pmThe unexpected-startup symptoms you describe exactly match those of a thermostat that's been left on at a very low setting, instead of being turned off. I know I've done that a few times, only to be awakened in the early morning hours as the furnace unexpectedly turns on.This happened to us at exactly the same moment I adjusted the heat temperature on the truck heater while driving down the highway. Imagine my surprise when the propane heater turned on! In fact, I made a post on this only to discover that we needed to push the thermostat as described by Andy. I felt like a dull light bulb.
Re: Furnace Issue Reply #10 – February 01, 2017, 07:25:59 pm This is the exact same problem I had with Ghost Rider (2005 RB) out in Q. I pulled the fuse when I went back to the Phoenix area and reinstalled when I came back. It was COLD in Q and I didn't want to waste propane. I'll check out my thermostat now that we are back home.THANKS!
Re: Furnace Issue - followup Reply #11 – February 10, 2017, 05:14:49 pm On further investigation I found the problem. Seems the plastic tab that is used to open the circuit broke off and stayed in place. The main reason I missed this was the factory put a sizable amount of 'grease' on the tab to help with wear I assume. They also put a drop of glue on each corner of the cover. I understand and get the reasoning. LD builds a RV to stay together but not take apart.
Re: Furnace Issue Reply #12 – February 10, 2017, 05:28:15 pm Oho! When I wrote "Unless that triangular plastic tab is completely broken off...", I thought that was extremely unlikely. But now I can claim to have mystical insight. ;-) 4 Likes
Re: Furnace Issue - followup Reply #13 – February 10, 2017, 11:51:14 pm Quote from: colddog - February 10, 2017, 05:14:49 pm I understand and get the reasoning. LD builds a RV to stay together but not take apart.No one can accuse LD of scrimping on the adhesives. They glue any and everything that can possilby come loose.My favorite, not really, is the rear license plate lights. The are glued in with polyurethane and usually are usually destroyed in the process of removing them, to replace a burnt bulb.Larry