Furnace question for you pros out there...

[FishinFools]

Had a chance to use the new trailer this past weekend as a deer hunting outpost in N. WI.  We have used our Suburban NT-16SQ furnace before, without incident.  This weekend, however, we had indoor temps in the 20's when returning after sitting on stand all day.  All three days, the same thing happened:  with the gas turned off at the tank, I moved the thermostat up.  Nothing happens.  No 'click' in the thermostat.  No blower turning on.  When I first went to inspect the fuse that protects the furnace circuit alone, the blower turned on upon reinsertion of the fuse.  From that point on, the furnace worked perfectly.  Until the next day, where in the morning I would turn the furnace off and the whole scenario repeated again each day.  The blower would not start up unless I pulled and reinserted the fuse.  Once started, the furnace works perfectly.

Any thoughts on what might be the cause of such behavior?

Thanks in advance, and Happy Thanksgiving!

Edited November 26, 2015 by FishinFools

[RiverChuckNorris]

I had to change out my thermostat and have seen other posts with guys doing the same to fix a tempermental (pun intended) furnace in my IC.  I'm no electrician, but that'd be my 

[Surface Tension]

 By removing the fuse your resetting the furnace and the start up sequence begins.   Normally when a reset is required the furnace went into shutdown after a number of failed attempts somewhere in the start up sequence.  Going into shutdown and turning off are two different things.  Question,  how are you "shutting off" the furnace?  Turning the gas off is not turning the furnace off.

 

[tinker]

I'm not familiar with your furnace but most furnaces with electronic ignition controls will reset themselves by turning the power off and on.

Tinker

[Boar]

In My IC, my start up up sequence is, to SLOWY, open the tank vaulve, if one opens it to vast ther is a fuel pressure gauge that will shut down the system, thinking its get to much fuel to fast from quickly open the valve, thinking there is a fuel leak. I slowly open vaule, I go in and push the thermometer temp swithc to desired temp. thats it. furnace kicks on.

 QOUTE......  with the gas turned off at the tank, I moved the thermostat up.  Nothing happens.  No 'click' in the thermostat.  No blower turning on.  When I first went to inspect the fuse that protects the furnace circuit alone, the blower turned on upon reinsertion of the fuse.  From that point on, the furnace worked perfectly.  Until the next day, where in the morning I would turn the furnace off and the whole scenario repeated again each day. 

I dont know i im understanding what ur doing,  according to ur post your turning the tank of and expecting the thermostat to kick the funace on with no fuel cause the tank is off.

Shut the system down completely, there is a reset but on the furnace, cant remeber where but its ther. Ive had a reset issue before long time ago. try that. then open tank realy slow, then push thermostate to desired temp. when you leave for awhile, just turn it down dont shut it off. if you shut the furnace off, turn the tank off too.

[FishinFools]

 By removing the fuse your resetting the furnace and the start up sequence begins.   Normally when a reset is required the furnace went into shutdown after a number of failed attempts somewhere in the start up sequence.  Going into shutdown and turning off are two different things.  Question,  how are you "shutting off" the furnace?  Turning the gas off is not turning the furnace off.

 

To shut the furnace down, I turn the thermostat all the way to "off" and then turn the gas off at the tank.  I do not have any manual switch installed on the furnace power feed.  Any thoughts on trouble shooting?

[Don Julio]

The next time you use the furnace try this.  Get furnace to run and up to temperature, then turn off just the thermostat, sit down inside and see if the furnace re-starts. If it does you have a bad thermostat. The off function is not working correctly. Replace thermostat. On mine you have to push a lever on top of thermostat to shut it off. I'm thinking its trying to start when you are gone and with no gas on, it times out trying to start. Pulling fuse resets the furnace and will light now since the gas is back on. My 2 cents with a shot of Don Julio!

[FishinFools]

You could be right!  I'll try it.  I'll also have a chance to do some investigating with a multimeter. 

[FishinFools]

Now that muzzle loader season is over, I had a chance to do a bit of investigation of my thermostat issue.

Switch in the "off" position: 24v metered wire to wire in the thermostat.  Move lever to call for heat:  0v wire to wire.  

I moved the anticipator down a bit, and If I wait 15 seconds after moving the lever to call for heat, the fan turns on.  

Turn on the gas, call for heat...everything works fine.

thanks all for the comments.