Wood furnace fire going out

[Quietwelder87]

Hi all, I'm new to wood indoor wood burning. We bought a house with a falcon f-2500 wood electric furnace, company no longer makes stoves/furnaces. House is built in 2014 and would be pretty airtight which may be another issue. Plumber said should be a 4" fresh air intake near furnace, but there isn't. (might help, don't think it's the problem)

Last night overnight temp was - 10C (14f)

Wood is oak, moisture 15-16%.

We are having a problem with the fire going out when the time between Heating intervals is too long(I believe). When wood thermostat calls for heat it opens the fresh air damper at back of furnace.

Would there be another small vent which let's enough air to get in to keep fire from smothering?

Chimney was cleaned out, fire bricks had some cracks so I didn't take out. Do I have to take those out to clean? If so I'll get new bricks and can do that.

Sorry for long post, wanted to get as much info as I could.

Thanks

 

[brenndatomu]

Wood is oak, moisture 15-16%.

We are having a problem with the fire going out when the time between Heating intervals is too long(I believe). When wood thermostat calls for heat it opens the fresh air damper at back of furnace.

Would there be another small vent which let's enough air to get in to keep fire from smothering?

Is it really 15-16%? How exactly are you testing it?
There has to be a little air getting to the fire between calls for heat...looking at the pic of the damper, there is a screw on the bottom there, with what looks like a tab on it...can that tab be turned to prop the damper door open a bit? If that's how it's designed to work, that is a little janky IMO...

 

[Quietwelder87]

Hi, bought a cheap tester and shoved the prongs far as I could and most pieces tested between 15 and 16. Wood was cut and split a year ago. Got the house down to 68 on weekend and tried again, added wood once and fire was burning nice, good coals. House got up to temp and went to check an hour later and fire was out and smoking like crazy.

So that little tab is for a power outage, prop it open and you will get some air to fire. It allows some air to circulate naturally through ducts with out getting too hot. When power come back on damper opens and the tab drops back down.

I could probably just tighten that up so it props open alittle at all times? Furnace Fan automatically kicks in if temp in exchanger(plenum?) gets to 130 I think it is, might just keep house hotter..

 

[all night moe]

Oak takes 3 yrs to get below 20%. Very important for any wood burning furnace that's naturally drafted.

Should be measured on a fresh split at room temp. Stick the prongs in the fresh face and parallel with the grain.

 

[brenndatomu]

Should be measured on a fresh split at room temp. Stick the prongs in the fresh face and parallel with the grain.

Yup...if tested on the outside, or ends, the reading is meaningless.
Best test is from right in the middle.
I bet OP finds his wood at 25%+ when tested properly.

 

[brenndatomu]

I could probably just tighten that up so it props open alittle at all times? Furnace Fan automatically kicks in if temp in exchanger(plenum?) gets to 130 I think it is, might just keep house hotter..

A trick that was commonly used by some on this forum running a certain brand furnace was to bend a paper clip to hang in the intake to keep the damper from seating fully.

 

[all night moe]

A trick that was commonly used by some on this forum running a certain brand furnace was to bend a paper clip to hang in the intake to keep the damper from seating fully.

When I first moved in here, my furnace air draft was wired wide open. No T-stat in use. It was run wide open with only the fan limit switch as the only blower control. I soon had eliminated the wire and fashioned a hook so I could control the draft intake. I run it like a woodstove now. After I get it going, I adjust the hook so it leaves a 1/4'' gap at the draft door. Limit switch does the rest until the wood burns up. This is the way it's staying till I switch all to hydronic. If I ever pass go...

 

[Quietwelder87]

Yup...if tested on the outside, or ends, the reading is meaningless.
Best test is from right in the middle.
I bet OP finds his wood at 25%+ when tested properly.

Yep your right, I guess I'm about as green as the wood, split one piece and it was 27%. Guy told me it would be good to burn this winter.

Might have to find some well seasoned stuff for this year then. Or would mixing it with some pine or tamarack work since they burn hot?

 

[Quietwelder87]

A trick that was commonly used by some on this forum running a certain brand furnace was to bend a paper clip to hang in the intake to keep the damper from seating fully.

I think I might try that as well, seems odd to me that they would close damper all the way.

 

[all night moe]

Yep your right, I guess I'm about as green as the wood, split one piece and it was 27%. Guy told me it would be good to burn this winter.

Might have to find some well seasoned stuff for this year then. Or would mixing it with some pine or tamarack work since they burn hot?

Find seasoned wood. Don't waste heat energy to send that moisture up the chimney from the oak. Put that oak aside. When it's dry you'll be glad you did.

 

[brenndatomu]

Might have to find some well seasoned stuff for this year then. Or would mixing it with some pine or tamarack work since they burn hot?

In most places it's exceedingly difficult to find wood to buy that is actually dry (sub 20%) if you do find someone with affordable dry wood, don't lose their number, you have found a unicorn!
Pine or tamarack would work, but only if it's dry (same test) if it's not dry, it'll burn, but it'll cause creosote too...that's why everybody says pine will burn your house down...they are burning wet wood!
If you bring in some of your wood, split it small, stack it near (but not too near!) the furnace, it will dry down a good bit in a few weeks...so then you just need to set up a rotation the rest of the winter

 

[all night moe]

stack it near (but not too near!) the furnace, it will dry down a good bit in a few weeks...so then you just need to set up a rotation the rest of the winter

I do this. Mine is not as wet though. I also have a box fan across the basement, on the floor, blowing towards the furnace enhancing air circulation. Helps tremendously. I should have mentioned this.

Tired....time for bed.

 

[Quietwelder87]

In most places it's exceedingly difficult to find wood to buy that is actually dry (sub 20%) if you do find someone with affordable dry wood, don't lose their number, you have found a unicorn!
Pine or tamarack would work, but only if it's dry (same test) if it's not dry, it'll burn, but it'll cause creosote too...that's why everybody says pine will burn your house down...they are burning wet wood!
If you bring in some of your wood, split it small, stack it near (but not too near!) the furnace, it will dry down a good bit in a few weeks...so then you just need to set up a rotation the rest of the winter

OK good to know. I think I'll see if I can find a couple chords this year, burn this stuff next year, and the stuff I just cut after that then hopefully I'll have a good rotation set up. The neighbour had said you could burn oak right outta the bush, I know he's full of chit but didn't think it would be 3 years to season either. Thanks to the two of you for the help!

 

[brenndatomu]

Yeah oak is one of the longest to dry, it really likes to take it's time to let go of that moisture!
If you can find anyone with Ash, that dries fast, especially since it's almost always dead for a while already these days. Maple dries pretty fast, and hard maple has pretty good BTUs.
Boxelder, poplar, oh and beech is a really good one, if you can find it...great BTUs too!
Wood of any species will have the highest moisture content if cut in the summer when it was leafed out...winter is always better, and if it was dead/standing, that's the best...often times the wood from the top of a dead stander can be burnt very soon, to even right away sometimes.
Good luck!