External thermostat control for a Castle Serenity

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fronius

Member
Feb 5, 2016
3
Madison, wi
I'm thinking this Serenity stove would be a lot more useful for a small, well-insulated home and/or during the shoulder seasons, if it could turn off completely when it gets too hot (not just drop to low) and then turn back on when it gets too cold. Trying to get the timer set to operate the right amount of time per day is ridiculous, because it really depends on how cold it is outside. So, I was thinking, I could build a simple little circuit that would "press" the on/off button momentarily on a call for heat and "press" the on/off button back off after 1) heat is met, 2) more than 30 minutes have passed. I guess, since I'm new, I'm curious if mods can be discussed on this forum?
 
Yep that was one of my only dislikes of the Serenity,You can talk mods all you want so have at it.
 
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If your good with electronics, you could wire a small relay in series with your hopper switch. When the room gets too hot, have the relay open which will cut the pellet feed and shut the stove off.
 
I'm sure that would work for a shut down but probably wouldn't help with the startup.
 
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Your stove won't start either if it's on thermostat?
 
I'm pretty good with electronics and pretty good at making poorly engineered things from China work a bit better. :) Attached is a little draft schematic. I just have to solder a wire to either side of the on/off push button on the controller and connect it to my circuit which will "press" (connect) the button on a call for heat, and "press" (connect) the button again to turn it off when 1) the heat need is met and 2) at least 40 minutes have gone by. The 40 minutes is because the stove won't start again for 30 minutes after it is turned off. Since I'm not doing anything different, really, then if I were to stand next to the stove and turn it on and off manually, I feel it's a safe mod.

The way it works is when the thermostat calls for heat, the NO contacts on the thermostat close and the electrolytic capacitor is charged to pos 12V as current flows through the relays' windings. The pulse charge current through the the relay will close the relay switch momentarily (closing the push button connections and turning the stove on). (Once the capacitor is charged, it won't allow any current to flow). The charge current will also trigger a time delay relay that won't connect the circuit it is in, until 40 minutes have gone by.

When the temperature on the thermostat is met, the NC contacts close on the thermostat and connect the capacitor to neg. If 1) the NC contacts are closed and 2) time-delay relay is closed (40 minutes have passed), then the capacitor will discharge, again activating the relay switch momentarily, and the stove will turn off.
 

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An even better way to do it, might be with the remote. If I can get a spare remote, I can have my circuit just turn on and off the stove with the remote!
 
I'm pretty good with electronics and pretty good at making poorly engineered things from China work a bit better. :) Attached is a little draft schematic. I just have to solder a wire to either side of the on/off push button on the controller and connect it to my circuit which will "press" (connect) the button on a call for heat, and "press" (connect) the button again to turn it off when 1) the heat need is met and 2) at least 40 minutes have gone by. The 40 minutes is because the stove won't start again for 30 minutes after it is turned off. Since I'm not doing anything different, really, then if I were to stand next to the stove and turn it on and off manually, I feel it's a safe mod.

The way it works is when the thermostat calls for heat, the NO contacts on the thermostat close and the electrolytic capacitor is charged to pos 12V as current flows through the relays' windings. The pulse charge current through the the relay will close the relay switch momentarily (closing the push button connections and turning the stove on). (Once the capacitor is charged, it won't allow any current to flow). The charge current will also trigger a time delay relay that won't connect the circuit it is in, until 40 minutes have gone by.

When the temperature on the thermostat is met, the NC contacts close on the thermostat and connect the capacitor to neg. If 1) the NC contacts are closed and 2) time-delay relay is closed (40 minutes have passed), then the capacitor will discharge, again activating the relay switch momentarily, and the stove will turn off.
I'm late to the party here but would there be a simple way to make this work with a completely external thermostat that just turns the power on and off? I guess this would mean a way to make the stove turn on and start when the power is turned back on. Would it be bad if the stove was turned off with a thermostat that cut the power off? It wouldn't be able to do that high speed fan thing at the end so I could foresee there being some complications with that.