Woodchuck 2900 Help!

[Vipercar93]

We put in a woodchuck 2900 to heat our house, and I am new to heating a house with wood. We have a Nest thermostat and lately the stove has been blowing constantly, until there is not enough heat left and the blower shuts down. We have the thermostat at 72 and the house will regularly hit 80. We tried using it the other day in heavy winds outside and I must have overfired it, it hit over 800 on the flue temperature gauge with both doors shut. Normally the woodstove will run right around 200. From what I have been reading that is low.

I suspect there are multiple issues going on. I am in the process of reading through the forum stickies to help me understand what's going on in general. Thanks for trying to help me.

 

[Vipercar93]

Can I get a Moderator to move this thread to the correct forum please? (Wood Furnaces)

 

[maple1]

Not sure on exact issue. One part reads like not enough heat, another reads like too much?

I know nothing about these. But 800 makes it sound like you might have too much draft, for one thing. Which would require info about your chimney setup & maybe some pics.

 

[laynes69]

The thermostat only controls the damper on the furnace (or draft blower). If wood is burning in the furnace...the blower is going to run. Otherwise....the furnace would overheat since there's an air jacket around the firebox. One issue as mentioned sounds like an overdraft. Most of the older furnaces were easy breathers. If your burning good seasoned wood and fill a firebox...unless it's dampened down, it will take off. I would make sure all gaskets are sealing. How tall is your chimney and what size? Could you take pictures of the furnace? From the sounds of it....its possible the furnace is grossly oversized or it's just draft pushing it.

 

[maple1]

There should be something that controls a distribution blower though? That could have wonkiness?

There could also be a case here though of combustion blower talk getting mixed up with distribution blower talk, in the OP.

 

[laynes69]

Well to test the thermostat, he could turn it up without wood and if forced draft, watch it come on and shut off when the temperature is lowered. Also it's possible of too much air to initially charge the load to the point it just taking off. Lots of possibilities. Many people think a woodfurnace will shut off when the house hits a set temperature like a central furnace, but it's just not the case.

 

[maple1]

We also have no idea how this was installed.

 

[Vipercar93]

There are 3 positions on the thermo switch, 110 (off) 160(on) Then 200. Wouldn't the 200 be the setting that would force the blower on continually to prevent damage to the furnace? (though it says off again on the thermo switch)

The 800, yes I think there was too much draft, it was a windy day and the draft was amazing is a bad way. The chimney is a square 6 inch tile lined for about 25 feet to the cap, straight shot up the center of the house. You can see the flue design in one of the pics loaded going from the furnace to the chimney. When this issue happened you could see the squirrel cage blower at the front spinning pretty good. I have closed the damper down some since then, nearly fully closed.

Normally the furnace would operate around 200 and would click on/off when the thermostat called for heat. The woodchucks do have this ability. Now is this too cold? The house still heats.

The wood I am using is various hardwood tops cut down a couple years ago and finally cut up for firewood last fall. Mainly oak and maple.

There could be an oversize issue, the house is an old solid stone farmhouse, about 700 square feet on the ground floor. This is the only floor force fed. The basement and second floor are heated through residual and holes between the ground floor and 1st floor. In total we are looking over 1500 square feet, but only half of that is directly heated by the furnace.

The blower on the wood furnace turns off when the thermo switch sees below 110 degrees, the circulation blower will not turn on. The problem right now is above 160 it won't turn off now, even when the thermostat stops calling for heat.

So it could be that in the past when the thermostat stopped calling for heat the draft blower would shut off and the temperature in the firebox would follow suit, and this would shut off the circulation blower because it dropped below 110 degrees. So nothing might be wrong, just too much wood. Guess the wood wasn't seasoned enough and now that it's been sitting in a heated basement for X months it's burning better. I had not watched the thermo switch in the past to see what was happening in the airbox.

 

[laynes69]

So yes....800 is from high draft. Your grossly oversized with the woodfurnace (the radiant heat should heat the basement alone). When you say the blower wont shut off above 160, is this the forced draft blower or the circulation blower (little or big)? Also 200 is awfully low for a furnace like that in the fluepipe. At those temperatures, you will accumulate creosote so keep an eye on the chimney. It sounds like you'll need smaller fires.

 

[Vipercar93]

Ok thanks, I have been making smaller fires than earlier in the year, but it's still running warmer than when I had more wood. Must be that I had wet wood as well.

It is oversized, we plan on expanding the house, it's ran fine until now, must be inexperience with wood heat and wet wood!

We plan on expanding the house so went with the 2900 .