New Thermostat Question
I have this furnace in my TC. There are only two connections to the thermostat, and they are labeled “Thermo” and “+Thermo” I’m installing a new thermostat, and it’s connected like ...
Forum Discussion
Well, finding a digital thermostat with enough control over the cycle time that it would do me some good is proving to be impossible, so I’ve switched gears and decided to come at this from another direction. I still need to replace the RiteTemp t-stat because the up and down buttons have gotten difficult to use, but I’ll find a simple, non-programmable digital unit to replace it with. Had the Orbit t-stat not been so inaccurate on controlling the set temperature, I’d use it. I need the t-stat to have the +/- 1° swing that it claimed to be capable of. The RiteTemp is doing that now, so anything I replace it with needs to do that as well.
Just to clarify, my need is to have the LP furnace run “once in a while” during extreme cold periods (below 30°) so the waste tank and valve area stays above freezing, while the living area of the camper is being heated primarily by an electric heater. If I have access to shore power, the electric heater will be running on its HI setting, if I’m using my Yamaha 1000 for power, it will be on its LO setting. The electric heater has its own thermostat that works pretty well.
Under those conditions, rather than have the LP furnace be controlled by the digital t-stat, how about controlling it with a infinite cycle timer that has adjustable “ON” and “OFF” times? I’m thinking the furnace would need to run 10-15 minutes, then stay off for 1-2 hours. I would want it to do that endlessly, until I switched it back to the digital thermostat. I would monitor the temperature in the waste tank area with a wireless thermometer, and adjust the ON/OFF times so that it stays above freezing. The LP furnace will of course be adding heat to the living area while it’s running, but the electric furnace will react to that and not run as much. I see very little chance of overheating the living area while using the cycle timer, once I determine what the ON and OFF times need to be.
My LP furnace has a two wire connection to the thermostat. One is “+Thermostat”, and the other is “Thermostat”. I believe this is what’s referred to as a “millivolt system” as there is no power on these two wires. If you connect them together, the furnace starts a heating cycle, and when you disconnect them, the furnace turns off.
Functionally, what I think I need is something like this:
Adjustable Cycle Times Switch Module
From the description, it looks like if you supply the cycle timer with 12v DC, then you will have 0-120 minutes of ON and OFF time adjustability. I’m not locked in to this particular cycle timer though. I would prefer one in a case that could be mounted out in the open. In addition to the cycle timer, I would install a switch on the two thermostat wires so they were connected to EITHER the wall thermostat, OR the cycle timer. Never both.
The ON and OFF times need to be easily adjustable. That’s one thing I do like about this unit, is the simple, mechanical way of setting the cycle times. I would also install an on/off power switch to give the timer 12v, and jumper the trigger circuit on. The board would power up in a “triggered” state.
I would install this on the wall next to the furnace, where there’s easy access to the thermostat wires, and 12v power.
So, any recommendations on a cycle-timer like this, from a reliable brand? This one can be had for about $10, but the reviews (of course) range from “It’s great” to “it doesn’t work”.
Can you think of any reason why this wouldn’t work? It seems like a fairly simple, and inexpensive way to achieve what I’m wanting. Another option may be to just install another thermostat in the waste tank area, and a switch to control which thermostat is controlling the LP furnace. Thermostats aren’t typically designed to control a heating system below about 45°, and that’s about the highest I would want to keep that area. I see more of a chance of overheating the living area trying to use a thermostat like that than with a cycle timer.
:):)
Just to clarify, my need is to have the LP furnace run “once in a while” during extreme cold periods (below 30°) so the waste tank and valve area stays above freezing, while the living area of the camper is being heated primarily by an electric heater. If I have access to shore power, the electric heater will be running on its HI setting, if I’m using my Yamaha 1000 for power, it will be on its LO setting. The electric heater has its own thermostat that works pretty well.
Under those conditions, rather than have the LP furnace be controlled by the digital t-stat, how about controlling it with a infinite cycle timer that has adjustable “ON” and “OFF” times? I’m thinking the furnace would need to run 10-15 minutes, then stay off for 1-2 hours. I would want it to do that endlessly, until I switched it back to the digital thermostat. I would monitor the temperature in the waste tank area with a wireless thermometer, and adjust the ON/OFF times so that it stays above freezing. The LP furnace will of course be adding heat to the living area while it’s running, but the electric furnace will react to that and not run as much. I see very little chance of overheating the living area while using the cycle timer, once I determine what the ON and OFF times need to be.
My LP furnace has a two wire connection to the thermostat. One is “+Thermostat”, and the other is “Thermostat”. I believe this is what’s referred to as a “millivolt system” as there is no power on these two wires. If you connect them together, the furnace starts a heating cycle, and when you disconnect them, the furnace turns off.
Functionally, what I think I need is something like this:
Adjustable Cycle Times Switch Module
From the description, it looks like if you supply the cycle timer with 12v DC, then you will have 0-120 minutes of ON and OFF time adjustability. I’m not locked in to this particular cycle timer though. I would prefer one in a case that could be mounted out in the open. In addition to the cycle timer, I would install a switch on the two thermostat wires so they were connected to EITHER the wall thermostat, OR the cycle timer. Never both.
The ON and OFF times need to be easily adjustable. That’s one thing I do like about this unit, is the simple, mechanical way of setting the cycle times. I would also install an on/off power switch to give the timer 12v, and jumper the trigger circuit on. The board would power up in a “triggered” state.
I would install this on the wall next to the furnace, where there’s easy access to the thermostat wires, and 12v power.
So, any recommendations on a cycle-timer like this, from a reliable brand? This one can be had for about $10, but the reviews (of course) range from “It’s great” to “it doesn’t work”.
Can you think of any reason why this wouldn’t work? It seems like a fairly simple, and inexpensive way to achieve what I’m wanting. Another option may be to just install another thermostat in the waste tank area, and a switch to control which thermostat is controlling the LP furnace. Thermostats aren’t typically designed to control a heating system below about 45°, and that’s about the highest I would want to keep that area. I see more of a chance of overheating the living area trying to use a thermostat like that than with a cycle timer.
:):)
