I go through thermostats often... from the "woodburner" propane stove runs a "two-wire" wire directly to the thermostat... I connect each "strand" to the correct screw... it appears to pick when it will work... often I have to hotwire it... any idea to a solution is appreciated... need more information let me know... thanks... M

Maybe I will read further... hmmm... no help yet forthcoming... of course on east coast it's 5:02am... sleepy time now for me...

Post the brand amd EXACT model of the thermostat you are using

It's a LUX (#stamped on all pieces 220907A), also on the sticker is T101143 / PSM40, Heat and Cool, HTG: 0.15 to 1.2 Amps, CLG: 1.5 Amps Max. and Max 30 Volts A.C... bar code 1011430001346091... hope this helps?? And thanks for responding hvac1000

Here is your manual which you may have a paper copy of but sometimes it is nice to have on the computer. The R and W terminals are the ones to use. Since your system is probably a milivolt system and not powered by 24 volts this could be a problem since the milivolt generator wiring can only be run a short distance or it looses power. In reading the thermostat file it does not mention that this thermostat is milivolt compatible so I have no idea if it is supposed to work. The main reason is the built in heat anticipator in the thermostat you have now. That acts like a mini resistor so to speak and I have seen that cause problems before with minivolt systems.

http://www.luxproducts.com/ART/support/T10-1143SA_WebManual_ENG.pdf

Something to try. Use the two thermostat wires but connect them to a switch instead of a thermostat. See if when you turn the switch on and off a few times if the unit works. If it does then the thermostat is at fault. If not then the wires are to long or the unit is at fault. Good luck.

Have used the proper screws (R and W)... I believe you are correct about the wiring being "wrong"... am going to work on it today and see what I come up with... I like your switch idea and hadn't thought of it... thanks a lot!! I really appreciate your help, thanks...