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

Go Back   Sunline Coach Owner's Club > Technical Forums > Repairs and Maintenance
Click Here to Login

Join Sunline Club Forums Today


Reply
 
Thread Tools Search this Thread Display Modes
Old 01-14-2009, 05:30 PM   #1
Junior Member
 
Join Date: Jan 2009
Posts: 9
SUN #774
al_in_cedar
is it the Thermostat? 1985 T-1350

okay, i searched the forums and didn't find an answer to this question...

FIRST: Im a newbie.. let me get that out of the way... I just picked up a real nice 1985 Sunline T-1350. It's exactly what I've been looking for and in very good shape. ($900)

Here is the problem.. I KNOW the furnace works(ed). I can light the pilot light and have actually had it fired up and had it heating. However... I kind of tapped on the thermostat a couple of times and the heater stopped heating.

Here is what I can tell you:
1. the pilot light is lit and is very easy to light and STAYS lit.
2. the stove works fine.
3. the fan kicks on when I want it too and turns off as it should.

the only thing missing is the FLAME part which provides the HEAT part.

I am thinking that the thermostat stopped working when I 'tapped' on it. Although there isn't much to it, I dont know anything about it...

Anyone out there that can throw this newbie a bone and tell me what to try? If it's just the thermostat, i'll run out to the thermostat store tomorrow, but I need some input from the pro's...

All in all, I'm real happy with my purchase and I think I have a real nice box..

THANKS IN ADVANCE
__________________

__________________
al_in_cedar is offline   Reply With Quote
Old 01-14-2009, 10:29 PM   #2
Moderator
 
JohnB's Avatar
 
Join Date: Nov 2006
Location: Ohio
Posts: 12,643
SUN #89
JohnB is on a distinguished road
H'mm a 1985 unit. Do you have a model/make number of the furnace? I can attempt to look it up.

And any pics of the unit where the gas valve/pilot light is?

This much it "sounds" like. Tell me where I go wrong.

The pilot lights and stays lite? This older one you have to actually lite the pilot. This means the thermocouple is OK.

The fan runs but does not lite. Well the T stat is 1/2 working or the fan would not run.

I really need to see the model/brand you have and what vintage it is. The old ones where pretty mechanical and the gas valve sort of ran the show. The new ones are electric controls.

Let me know what you have and may be able to help further.

Oh, welcome to the club. Glad to have you with us.

John
__________________

__________________
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC

Google Custom Search For Sunline Owners Club
JohnB is offline   Reply With Quote
Old 01-15-2009, 07:44 AM   #3
Senior Member
 
Join Date: Jun 2007
Location: New Hampshire
Posts: 1,025
SUN #292
Honda03842 is an unknown quantity at this point
Sail Switch

Assuming the following, the pilot is lit, the pilot knob is turned to ON, the white switch is on at the thermostat and the temperature is set above the ambient.

From your description all these conditions have been met because the furnace's blower is working indicating the thermostat is working.

The final element is the sail switch, a small mechanical switch with a 'sail' on it. It is used to detect that the blower is running before the furnance will turn on, the air blows on the switches sail and closes the switch.

Is there a schematic of your furnace under the front cover showing the sail switch? If you can find the wires that go to and from the sail short you can jump out the sail switch and if it works the problem is the switch.

I also might consider loosening and retightening the screws on all the wires. Sometimes in these old trailers you get contact corrision; similarly if there are any slide on connections.


Norm Milliard
__________________
Honda03842 is offline   Reply With Quote
Old 01-15-2009, 12:30 PM   #4
Senior Member
 
Steve Collins's Avatar
 
Join Date: Apr 2007
Location: New York
Posts: 1,846
SUN #264
Steve Collins is an unknown quantity at this point
If there is no air conditioning in the unit, then the thermostat is most likely the old style thermo-mechanical switch. The ones I remember had a coil of metal to sense the temperature, and a mercury switch. When the coil expanded or contracted, it changed the tilt of the mercury switch to the point that it turned on or off. The temp set lever or dial adjusted the position of the switch/coil in a circular fashion.

If that's the type of thermostat that's there, then I believe those are two wire (+ & -) and the thermostat can be bypassed by either jumpering the wires, or leave the cover off and turn the temp up so that you can see the mercury cover both contacts inside the little glass tube.

Short of physical damage to the thermostat, they just don't wear out. But as Norm stated, dealing with corroded connections is an absolute must.

There's a second kind of thermo-mechanical thermostat that just has a tab of bimetal (moves based on temp), and a slider to adjust the set point. Based on the temp, the tab bends until it touches a contact, making or breaking the circuit. This type of thermostat can wear out due to corrosion on the contacts and just plain metal fatigue. But again, if it is two wire, it's no problem to jumper the wires to insure that the furnace is set to run while trouble shooting.

If you determine that the thermostat needs replacing, I would recommend the Hunter digital conversion ($20 at Wal-Mart). It's easy to do and costs much less than replacing an RV specific thermostat. It is much more accurate than a thermo-mechanical one, and gives a easy to read temperate display even when not using the furnace.

The sail switch and gas knob to ON are the primary areas I'd look at.
__________________

'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
1999 to 2011: '99 Sunline T-2453
SUN264 * Amateur Radio kd2iat monitoring 146.52
Steve Collins is offline   Reply With Quote
Old 01-16-2009, 09:13 PM   #5
Moderator
 
JohnB's Avatar
 
Join Date: Nov 2006
Location: Ohio
Posts: 12,643
SUN #89
JohnB is on a distinguished road
Re: Sail Switch

Quote:
Originally Posted by Honda03842
Assuming the following, the pilot is lit, the pilot knob is turned to ON, the white switch is on at the thermostat and the temperature is set above the ambient.

From your description all these conditions have been met because the furnace's blower is working indicating the thermostat is working.

The final element is the sail switch, a small mechanical switch with a 'sail' on it. It is used to detect that the blower is running before the furnance will turn on, the air blows on the switches sail and closes the switch.

Is there a schematic of your furnace under the front cover showing the sail switch? If you can find the wires that go to and from the sail short you can jump out the sail switch and if it works the problem is the switch.

I also might consider loosening and retightening the screws on all the wires. Sometimes in these old trailers you get contact corrision; similarly if there are any slide on connections.


Norm Milliard
Adding to Norms point on the sail switch, that is if yours has it. The battery on the camper needs to be charged enough to make the blower run fast enough to make the sail switch close. Or you need to be plugged into shore power and then the blower is running off the converter and has enough volts to run fast enough.

Even the new campers with DSI will stop the fire (gas valve) if the battery drains down too far, the wind cannot trip the sail switch and then the flame goes out.

Something to check if yours has a sail switch and you are running off battery only.

Try and find a Model number. I found a 1985 manual on a Hydrotherm but do not know if it is your model.

John
__________________
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC

Google Custom Search For Sunline Owners Club
JohnB 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
Is this a Fantastic Vent thermostat? EMD_Driver Sunline Community 7 11-25-2009 08:50 PM
Air Conditioner Thermostat MOKID Repairs and Maintenance 4 08-25-2009 03:07 PM
1982 Sunline T-1350 Manassas, VA Rich Introduce Yourself 5 08-17-2009 12:57 PM
New to me :: 1985 T-1350 al_in_cedar Sunline Travel Trailers 1 01-14-2009 07:35 PM
Possible Thermostat problem??? al_in_cedar Repairs and Maintenance 0 01-14-2009 05:16 PM


» Featured Campgrounds

Reviews provided by

Disclaimer:

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


All times are GMT -6. The time now is 07:49 AM.


×