Which Wood Furnace

[brenndatomu]

Sounds like the fan/limit switch was set about right from the factory. If the firebox and heat exchanger are getting gunked up then you either need to set the fan temp back up or you have wet wood, or maybe some of both. If it was actually dripping then I'd lean toward wet wood and maybe you have the air cut back too far also. If it is too hot then load less wood. Less quantity per load and then less often if it is still too hot. You may have to let your house temp fluctuate a bit so that you can get the furnace hot on each load, can't run 'em on "low" all the time. It has been pretty warm, it can be hard to run a wood furnace properly in this kind of weather.

I wouldn't want the blower running all the time, but it will run much more than a fossil fuel furnace.

As far as getting heat to the far rooms, you will have to damper the close rooms back until you get the balance that you want. It may require bumping the blower speed up, but then that means you will have to screw with all your settings again (temp switch and duct dampers)

 

[Lawson111]

Sounds like the fan/limit switch was set about right from the factory. If the firebox and heat exchanger are getting gunked up then you either need to set the fan temp back up or you have wet wood, or maybe some of both. If it was actually dripping then I'd lean toward wet wood and maybe you have the air cut back too far also. If it is too hot then load less wood. Less quantity per load and then less often if it is still too hot. You may have to let your house temp fluctuate a bit so that you can get the furnace hot on each load, can't run 'em on "low" all the time. It has been pretty warm, it can be hard to run a wood furnace properly in this kind of weather.

I wouldn't want the blower running all the time, but it will run much more than a fossil fuel furnace.

As far as getting heat to the far rooms, you will have to damper the close rooms back until you get the balance that you want. It may require bumping the blower speed up, but then that means you will have to screw with all your settings again (temp switch and duct dampers)

Ok thank you for the help ill try setting them back to factory and see what happens. If I get that bad creosote buildup I will try turning it up 10 degrees at a time because I know my wood is dry ( it has been checked with a meter). Should I always try and keep a 50 degree difference between on and off? I bought one of them temp gauges for the flue and I use the damper on the stove pipe to try and keep it around 250-300. I'm trying to find the happy medium where the stove runs good but doesn't burn out to fast, I'm only getting about a 5 hour burn out of a full firebox. Not sure what the heat exchanger is either, maybe I do I might just call it something different?

I was going to go that route with the duct dampers but didn't know if there was any other suggestions before I tried that.

 

[sloeffle]

I bought one of them temp gauges for the flue and I use the damper on the stove pipe to try and keep it around 250-300. I'm trying to find the happy medium where the stove runs good but doesn't burn out to fast, I'm only getting about a 5 hour burn out of a full firebox.

Are you using a manual damper ? If you are, I would recommend a barometric damper setup per the manual.

 

[brenndatomu]

Not sure what the heat exchanger is

The channel above the firebox that the smoke/flue gasses (heat) have to go through on the way out when the bypass is closed. It picks up heat in the exhaust stream and transfers it to the air, hence the term heat exchanger.

You can set the fan switch for less temp differential but the fan will cycle on/off more often

 

[Lawson111]

@sloeffle yes I do have one but at the moment I am not using it. It just stays open and I'm trying to get the flue temp set by adjusting the vent on the ash door.

@brenndatomu ok that's what I thought it was but wasn't sure. And right now as we speak I have limit switch set to 150on and its in between 90-100 for off, the fan is on low and it runs for about 10-15 mins. Is it better to have it run long periods of time like the or short ones more often? I can move the off up 100-110 if it's better to have it run short periods of time. Or even maybe go 160on 110 off. Just trying to get it dialed in now that I got some experienced help.

Thanks guys I really appreciate it.

 

[brenndatomu]

And right now as we speak I have limit switch set to 150on and its in between 90-100 for off, the fan is on low and it runs for about 10-15 mins. Is it better to have it run long periods of time like the or short ones more often? I can move the off up 100-110 if it's better to have it run short periods of time. Or even maybe go 160on 110 off. Just trying to get it dialed in now that I got some experienced help.

You have to find a balance that works for you. The problem is, that as the wood burns down the "on" time gets shorter and the "off" time gets longer...seems to waste a lot of heat up the chimney to me. You really notice this during extreme cold weather. Off time doesn't matter near as much if you have a duct system that flows gravity heat well (good rise on your runs)

@sloeffle yes I do have one but at the moment I am not using it. It just stays open and I'm trying to get the flue temp set by adjusting the vent on the ash door.

Did you set it with a gauge? To me there is no way to set draft based solely on temp. Proper draft settings can make a huge difference. I'd set that baro up properly, get used to a "normal" baseline before making changes...

 

[Lawson111]

I've never used a barometric damper before I have one on my oil furnace but no idea how it works. So if you don't mind could you explain how to use one and put it in? Or lead me in right direction. The only thing I know about them and this could be totally wrong is the allow air to be pulled from outside of flue so you can get draft. Now I just have manual damper installed in flue so I can choke fire down if it gets to hot or I have a runway and need to shut it down. Wouldn't putting a barometric damper in basically get rid of the need for a manual damper and what would you do incase of a runway or chimney fire? This is what I'm referring to as manual damper. Your saying I need to use a barometric damper with this or ditch this and just use barometric damper?

 

[brenndatomu]

You could leave the manual damper in for emergency use, just leave it open most of the time. You could just set the draft with the manual damper (and a manometer) but draft can change a lot with wind and whatnot, that's why most wood furnace manufacturers recommend a baro.
A baro doesn't create the draft, only control it. The draft comes from the heat of the fire, a column of warm air rising in the chimney, the hotter the air in the chimney or the cooler the air outside...more draft. It is nice to have the automatic draft control that a baro offers. They can cause more buildup in the chimney for some though...
Basically the baro is just a weighted flap that is adjust with a manometer to open at a specific draft setting. It will open just enough to keep the draft that the wood burner "sees" at your desired setting.
You install it by putting a tee into the stove pipe ahead of the chimney, once the baro is in the tee you need to get it plumb and level, then it can be set with a relatively inexpensive manometer (PM me if you need/want one)

 

[Lawson111]

I don't have much room for a T I might be able to make it work without changing my current setup. I chose to set it up this way way I didn't have much of a horizontal run I wanted to avoid as much creosote buildup as possible

 

[brenndatomu]

You have TONS of room for a tee! It can go anywhere on that diagonal run. It doesn't have to be flat, the baro has to be level, but the tee does not have to be flat to do that

 

[Lawson111]

Ok I thought it had to be flat when you said it has to be good and level

 

[maple1]

@sloeffle

yes I do have one but at the moment I am not using it. It just stays open and I'm trying to get the flue temp set by adjusting the vent on the ash door.

Not sure what this means, the 'it just stays open' part. Does this mean there is a baro installed but it is open all the time? Or there is no barometric damper installed at all? I don't see one in your pic, but can't see all the pipe either. But the staying open all the time part is a bit of an alarm bell - having it open all the time would mean that your furnace is getting no draft, more or less.

 

[Lawson111]

I don't have a barometric damper installed just the damper in the flue and yes that's what I leave open. I was using it to regulate flue temps before when I would leave the knob on the bottom of my ash door open all the way. Now I'm using the knob to control the flue temps and leaving the flue damper open. I called shelter and they didn't even recommend having a flue damper installed unless it was absolutely necessary.

 

[Highbeam]

just the damper

Key damper. "Open" means it is reducing draft only minimally.

 

[Lawson111]

Key damper. "Open" means it is reducing draft only minimally.

Yea I know I put it in just to cut the draft back so I can get longer burns and not such a hot fire when I load the stove up with wood (what it's meant to do) or if I have a chimney fire I can shut it almost completely.

 

[brenndatomu]

Ok I thought it had to be flat when you said it has to be good and level

I said plumb and level but I guess I should have specified the baro not the tee.

Yea I know I put it in just to cut the draft back so I can get longer burns and not such a hot fire when I load the stove up with wood (what it's meant to do) or if I have a chimney fire I can shut it almost completely.

The thing about a key damper is people sat they put them in in case of a chimney fire but chances are you won't be there to shut it at that time anyways. The other thing is, and this is a biggy, those dampers only block 80% of the pipe (by design) and a major chimney fire will EASILY be able to feed off of a 20% opening, because at those temps, draft readings go off the charts.

As I said before though, you can use a key damper to control draft, but you still need a manometer to set it. A baro will be much more constant with the draft though...but then they cool the chimney...so both damper types have their pitfalls

Might be a good time to ping @Wisneaky , he has one of these furnaces, might have some good advise for ya

 

[Lawson111]

Has anyone ever hooked up there draft blower to the Honeywell thermostat fire the firebox? I never use mine right now because the temperature in the house is never low enough to have the blower kick on. To me is seems kind of foolish having the blower hooked up to a thermostat that goes off the temp. of the room, when the room gets cold enough for the blower to kick on this usually means the fire is out or very low, so what is it actually doing? If it is hooked up to the firebox thermostat you could have it turn on and off based on what ever temp. you set it to via the firebox, this wayit actually doing something before the fire goes out. You will lose 15-20 degrees a lot faster in the firebox than you will 5 degrees in your house. Maybe my idea is crazy and doesn't make sense I just wanted to see if anyone that owns a furnace with a draft blower kit has done or tried this.

 

[brenndatomu]

T-stats wouldn't have the range to do this, 99* is usually as high as they go. You could use a temp controller with a thermocouple or RTD probe to accomplish what you are suggesting though. I think this could work out pretty well actually. The house t-stat could be tied into the circuit too...the idea would be to keep the firebox in its "happy place" without blowing too much heat up the flue. You can read about the temp controller setup that 3fordasho and myself have setup over in the "Everything Drolet Tundra - Heatmax" thread...temp controller comes in around page 15 IIRC...

 

[Lawson111]

T-stats wouldn't have the range to do this, 99* is usually as high as they go. You could use a temp controller with a thermocouple or RTD probe to accomplish what you are suggesting though. I think this could work out pretty well actually. The house t-stat could be tied into the circuit too...the idea would be to keep the firebox in its "happy place" without blowing too much heat up the flue. You can read about the temp controller setup that 3fordasho and myself have setup over in the "Everything Drolet Tundra - Heatmax" thread...temp controller comes in around page 15 IIRC...

Yea because like I said mine is never on because the house never gets below the temp I have the thermostat set to. If I could somehow hook it up to the Honeywell fan limit control switch that would be awesome. You could dial it in like you said to keep the firebox in its "happy place"

 

[brenndatomu]

...'course, if the house never falls below the tstat setpoint...what's the point?

 

[Lawson111]

...'course, if the house never falls below the tstat setpoint...what's the point?

72, house is never below 75 unless I let fire go out. We had a couple days with a high of 5f and the house was never below 75-76 and this is only putting wood on at 5am, 4pm and 11pm.