I’ve been playin’ around with my stovace (ya’ know, the EPA stove I converted into a furnace) because there was a couple of things I wasn’t happy with.
First, that clear ceramic front allowed a lot, a ton of radiant heat to escape the firebox into the basement… which is OK when we’re down there, but most of the time it’s not needed. I figured if I could somehow redirect that heat back into the firebox it could be used to heat the air flowing through the plenum instead. Aluminum, which reflects 100% of radiant heat, seemed like the answer. I picked up a thin sheet of aluminum from the hardware store, cut it to size, bent the sides over to rest on the door frame keeping it about a three-quarter inch from the ceramic, and made a couple “hooks” from aluminum strap so it hangs on the door. It’s light weight, easily removable with a couple fingers and doesn’t interfere with the operation of the door. By leaving the top and bottom open (about a half to three-quarter inch) it allows for some air convection so things don’t “overheat”. I can now place my hand a mere inch from the aluminum reflector and not feel any heat.
Three things resulted from this… The air coming from the heat vents upstairs gets “hot” a lot faster. The air from the heat vents remains hotter, longer. Redirecting the heat back into the firebox makes a lot hotter fire, which has allowed me to turn the combustion air intake “setting” way, way down… resulting in longer, yet still hotter, burns.
Second, it just seemed to me that way too much heat was escaping through the flue. I know these “new-fangled” EPA stoves aren’t supposed to use a flue damper, but being “old-school” I installed one anyway… just in case. My brick chimney runs up through the center of the house, always warm it sucks like an industrial vacuum… I figured it was supplying to much “suck”. I open the door of the firebox while the fire was burning and slowly began to close the flue damper until I saw the tiniest bit of smoke escape, then moved flue damper back open a bit. I now have the damper set where it’s still possible to open the door without smoke escaping, yet I’ve reduced the amount of heat escaping through the flue… it’s about half-way closed.
I’m still getting secondary combustion ignition and… holy crap does she get hot now, the outside of steel plenum gets hot enough to burn ya’ ASAP. That’s with the combustion air intake on it’s lowest “normal range setting”. I’m thinkin’ for overnight burns I’ll be able to set it on the absolute minimum, still have a “hot” fire, and get heat all night.
I use the gas furnace blower to move air through the wood furnace plenum, into the gas furnace plenum, and on to the duct work. It initially starts on low speed when the outside of the stack reaches 120[sup]o[/sup], and when the air in the gas furnace plenum reaches 95[sup]o[/sup] the blower kicks up one speed. As the “stovace” cools and the air in the gas furnace plenum drops below 95[sup]o[/sup] the blower reverts back to low speed until the outside of the stack drops below 100[sup]o[/sup], causing the blower to shut down completely. If at any time the gas furnace needs to run, the wood furnace controls are 100% over-ridden. I’ve set the gas furnace to fire if house temps drop below 60[sup]o[/sup]… I doubt it will ever run unless were gone for a couple days (and then I turn the thermostat way, way down anyway).
I’ll keep y’all updated as the weather gets colder and I keep playin’ around with it more.
First, that clear ceramic front allowed a lot, a ton of radiant heat to escape the firebox into the basement… which is OK when we’re down there, but most of the time it’s not needed. I figured if I could somehow redirect that heat back into the firebox it could be used to heat the air flowing through the plenum instead. Aluminum, which reflects 100% of radiant heat, seemed like the answer. I picked up a thin sheet of aluminum from the hardware store, cut it to size, bent the sides over to rest on the door frame keeping it about a three-quarter inch from the ceramic, and made a couple “hooks” from aluminum strap so it hangs on the door. It’s light weight, easily removable with a couple fingers and doesn’t interfere with the operation of the door. By leaving the top and bottom open (about a half to three-quarter inch) it allows for some air convection so things don’t “overheat”. I can now place my hand a mere inch from the aluminum reflector and not feel any heat.
Three things resulted from this… The air coming from the heat vents upstairs gets “hot” a lot faster. The air from the heat vents remains hotter, longer. Redirecting the heat back into the firebox makes a lot hotter fire, which has allowed me to turn the combustion air intake “setting” way, way down… resulting in longer, yet still hotter, burns.
Second, it just seemed to me that way too much heat was escaping through the flue. I know these “new-fangled” EPA stoves aren’t supposed to use a flue damper, but being “old-school” I installed one anyway… just in case. My brick chimney runs up through the center of the house, always warm it sucks like an industrial vacuum… I figured it was supplying to much “suck”. I open the door of the firebox while the fire was burning and slowly began to close the flue damper until I saw the tiniest bit of smoke escape, then moved flue damper back open a bit. I now have the damper set where it’s still possible to open the door without smoke escaping, yet I’ve reduced the amount of heat escaping through the flue… it’s about half-way closed.
I’m still getting secondary combustion ignition and… holy crap does she get hot now, the outside of steel plenum gets hot enough to burn ya’ ASAP. That’s with the combustion air intake on it’s lowest “normal range setting”. I’m thinkin’ for overnight burns I’ll be able to set it on the absolute minimum, still have a “hot” fire, and get heat all night.
I use the gas furnace blower to move air through the wood furnace plenum, into the gas furnace plenum, and on to the duct work. It initially starts on low speed when the outside of the stack reaches 120[sup]o[/sup], and when the air in the gas furnace plenum reaches 95[sup]o[/sup] the blower kicks up one speed. As the “stovace” cools and the air in the gas furnace plenum drops below 95[sup]o[/sup] the blower reverts back to low speed until the outside of the stack drops below 100[sup]o[/sup], causing the blower to shut down completely. If at any time the gas furnace needs to run, the wood furnace controls are 100% over-ridden. I’ve set the gas furnace to fire if house temps drop below 60[sup]o[/sup]… I doubt it will ever run unless were gone for a couple days (and then I turn the thermostat way, way down anyway).
I’ll keep y’all updated as the weather gets colder and I keep playin’ around with it more.
