Insert Running Hot Last Night

[unimog1300]

I have been reading here for a few months and have learned a bunch of stuff (raking coals to the front, shutting off blowers when cold start or reloading, moisture meter). Lots of great info here for sure. This might get long....

So I ran an insert (Earth Stove) in the basement for 3 years. I got smoke back in the basement after a couple of days, I found out the flue tile was blocked at the top with door screen and it plugged up. Was told I needed it lined so had that done with insulated flex stainless steel. Worked fine after that. We stopped after we had geothermal installed and I was working 3rd shift and thought it was unfair for my wife to have to do all the work at night.

Been heating with the insert on the main floor for several months now. Current wood is Ash, Oak, or Hickory....around 23% moisture content. That's all I have ready to go since I didn't know we were going to heat steady with wood again. After learning to get the firebox up to temp by shutting off both blowers (580 CFM total on high) I watched the window glass temps with the IR gun run to 590 and started to cut it back to half the air. Turned on the blowers and air was real hot as expected. Windows and door frames started to drop temp and then go back up slowly as I read they should do. Cut the air down again to less then a 1/4 and finally barely cracked open. Got really lazy flames as expected, some yellow buts lots of blue. It was hot I knew my windows weren't sealed tight by the clean areas on the glass, also one area of a door was definitely not sealing. Shut the air down as tight as it would go and still had rising temps but leveled off around 650. It started dropping then but the load of wood didn't last thru the night. I knew I needed better control of the air.

So it's been warm here in Illinois and I replaced all the door gaskets and the window gaskets. Couldn't find the window gaskets that were wrapped around the glass so replaced it with a layer of flat on the door frame and a layer on the frame that holds the windows in place, so gasket on front and back of glass, figured better seal? Cleaned and oiled both blowers while I was at it. First overnight fire last night same routine, blowers off, loaded with 23-24% Hickory over some hot coals, both vents wide open and the door cracked to get it going. Let the heat get to 500 this time and closed the door and shut the air to half. Got it stabilized at about 400-450 on the windows before bed with the air vents about a 1/16 open, lazy flames at 10:30. Wife wakes me up at 2:30 and says it smells hot down stairs. Go down and it's running 650 on the glass and 590 on the door frames, I close the air down all the way and have 275 + degree air coming out of the air discharge. 155 temp on the hottest brick above the face plate behind the insert, dropped to 100 about 5 rows up and cooler on up. Lots of lazy blue flames only and lots of wood to burn thru yet, started with 6 pcs(full). Monitored the temps for 20 minutes and it wasn't going down so I placed the 12" fan we use to push air deeper into the house facing the insert to pull heat away. That was working as I hoped, temps slowly down to 475 -495 on the glass and door frames. The center collapsed on the pile and didn't change the flames at all but after watching it with the fan blowing on it, temps finally started to go down when I took the fan off it. I'm guessing those temps were my peak of the cycle? 7:30 it was full of coals and I started it back up for the day. Windows both black with one small area hazy you could see flames thru.

So here's the info on the chimney. It's 13" square tiles and full brick all exposed and it's tall...24' off the top of my head and just under 7.5' wide. Just had the top 5 courses replaced and the top flue tiles too. This one is not lined at all and the draft is crazy good. Main floor flue is the middle one and the basement lined one is to the left.

The insert is from 1981 ish or so. The air comes in the lower front two knobs on the front and is pulled thru to the center of two heavy 3 sided runners going front to back. No longer in business so dead end on any operating temps for it. I actually have another one of these in a detached finished garage that the previous owner built as his man cave. We've lived here 18 years.

Was I on the verge of an over fire? event last night? All the air was shut off so I was not expecting to not control it after new gaskets. Too good of draft??? It was 15-20 mph winds and about 28 last night. Wasn't looking forward to lining it....not sure how that would have changed the situation last night. Would like to get more air flow from the fans but not sure that possible....might help me pull more heat from it? What do you all suggest? Makes my wife nervous when things get that hot. I'll try and ad pictures of the fire last night thru dirty windows, insert and info on it, and the chimney.

Thanks,
Steve

 

[jatoxico]

So the stove was in the basement installed with a liner and now its upstairs with no liner and venting into a 13" square tile flue?

 

[Ctwoodtick]

Is the insert on your main floor installed with a liner attached to it?
I don’t believe you can get accurate reading of stove temps from IR reading of glass. It reads accurate for surfaces other than glass.
If you have no stainless steel liner at all attached to that insert, that is referred to as a “slammer” install and not safe to use.

 

[moresnow]

Welcome to Hearth. Unless your attached to the old girl you might consider a upgrade in your setup! I'll let the pro's advise beyond that!

 

[unimog1300]

No this a different insert on the main floor with no liner. This insert is shown in the pictures.

There's two inserts in the house, basement and main level which we are using.

 

[Ctwoodtick]

No this a different insert on the main floor with no liner. This insert is shown in the pictures.

There's two inserts in the house, basement and main level which we are using.

I think I should have asked “are you using an insert/stove that does not have a steel liner?”1

 

[unimog1300]

Yes unlined 13" flue in the chimney pictured.

 

[Ctwoodtick]

Yes unlined 13" flue in the chimney pictured.

Ok, thanks for clarifying- I’ll let the pros give you some feedback on this type of setup.

 

[jatoxico]

None of the temps you listed are too high though measuring door frames and glass are not all that "diagnostic" if you will. If this was a freestanding stove most manufacturers will have you monitor the top. For my insert I have a thermo in the air vent that gives me a stove top reading. You can also use a cheap IR to shoot different areas including the exhaust vent if you can get a shot.

Short of that the next best thing to do is make sure no part of the stove glows. No dull or cherry red anywhere. If its night shut off the lights and inspect. Not the easiest with an insert but again try to view the stoves top through the vent. Such temps are much higher than what you report and commonly you don't want to exceed 800-850 and personally I am comfortable up to about 700-750 with my set up.

The concern I have for you with your smells and heat is that because there's no liner that you are building up creosote in the clay liner. If there is no connection of the insert to the liner the creosote and ash may be falling onto and around the insert where it burns off and smells. Also possible you had an outright chimney fire.

Need more info on how its installed and connection if any to that large clay liner.

 

[bholler]

So you ran a liner for the downstairs insert because it was unsafe to use without one but now you are using the upstairs insert without a liner???


What you are doing is unsafe

 

[SculptureOfSound]

I've got a completely different insert but have hit 700+ on the glass, stove top was about 675.

But I've also had 500 on the glass and 650 on the stove top. Checking the glass is really not reliable because it depends on how and where the fire is burning. When I had 500 on the glass and 650 stove top it was almost all secondaries burning so the heat was concentrating at the top rather than front of stove.

Describe the smell you had. I too am worried it's creosote in the chimney burning or fuming from being so hot

 

[unimog1300]

bholler:
The liner in the basement was about getting the chimney to draw. I had it done professionally since I didn't know anything about those things.

So can you explain how the upstairs flue draws so well and putting a liner in it would have changed what I described in my original post? That's what I'm trying to figure out. If I need a liner so be it but I'm not looking to spend that money if it doesn't "fix" what happened.
Thanks,
Steve

 

[bholler]

bholler:
The liner in the basement was about getting the chimney to draw. I had it done professionally since I didn't know anything about those things.

So can you explain how the upstairs flue draws so well and putting a liner in it would have changed what I described in my original post? That's what I'm trying to figure out. If I need a liner so be it but I'm not looking to spend that money if it doesn't "fix" what happened.
Thanks,
Steve

I am concerned with making sure you don't burn your house down or die from co leaking out around the insert as the fire dies down. What you are doing is asking for trouble.

 

[unimog1300]

Jatoxico: I was measuring the doors and glass since that's about all there is with surface area as part of the firebox that's exposed. Both sides of the insert are the air intake for the fans. The top box looking area across the top is where the hot air is exhausted out under the brass colored vent. I am using a cheap IR to check temps. I'll see if I can get to the firebox to check the temps thru the air intake for the fans, it's visible. I have been watching closely and have not noticed any glowing or dull red.

The smell is the same as when I get it hot before turning on the blowers, but that is short lived at that time.

I have zero idea how it's connected to the flue.

 

[bholler]

Jatoxico: I was measuring the doors and glass since that's about all there is with surface area as part of the firebox that's exposed. Both sides of the insert are the air intake for the fans. The top box looking area across the top is where the hot air is exhausted out under the brass colored vent. I am using a cheap IR to check temps. I'll see if I can get to the firebox to check the temps thru the air intake for the fans, it's visible. I have been watching closely and have not noticed any glowing or dull red.

The smell is the same as when I get it hot before turning on the blowers, but that is short lived at that time.

I have zero idea how it's connected to the flue.

Chances are it is not connected at all which is why i am concerned. How do you clean it without pulling it out?

 

[unimog1300]

It hasn't been cleaned but we have been burning for 2-3 months. We stopped burning it last night and are considering getting a new insert and lining it.

Now have to figure out what to buy.....

 

[jatoxico]

It hasn't been cleaned but we have been burning for 2-3 months. We stopped burning it last night and are considering getting a new insert and lining it.

Now have to figure out what to buy.....

If you're enjoying or at least benefitting from wood burning then this would be a great way to go. To run a liner for the existing stove wouldn't make much sense to me. It require an 8" liner where as most new stoves are six. It's possibly square and needs some kind of adapter, just not worth IMO.

New stoves run cleaner and extract more heat per load because of it. Budget units from Englander found at HD or Lowes are well loved here, Drolet is another that comes to mind. If you can safely install a unit that extends onto the hearth all the better.

 

[unimog1300]

To run a liner for the existing stove wouldn't make much sense to me. It require an 8" liner where as most new stoves are six. It's possibly square and needs some kind of adapter, just not worth IMO.

I agree 100%.

New stoves run cleaner and extract more heat per load because of it. Budget units from Englander found at HD or Lowes are well loved here, Drolet is another that comes to mind. If you can safely install a unit that extends onto the hearth all the better.[/QUOTE]

Thanks for that info I'll check that out. We wouldn't be afraid to spend some money on the right insert for but saving money works for us! Starting to look around here (Peoria, Illinois area) to see what dealers carry here. We would be willing to travel to get the right insert, have one ton truck and forklift to handle any of them once home. We would be heating 22-2300 sq ft.

 

[jatoxico]

Thanks for that info I'll check that out. We wouldn't be afraid to spend some money on the right insert for but saving money works for us! Starting to look around here (Peoria, Illinois area) to see what dealers carry here. We would be willing to travel to get the right insert, have one ton truck and forklift to handle any of them once home. We would be heating 22-2300 sq ft.

You will have to have the chimney inspected and measured and at the very least have it well cleaned. You also need to know the dimensions of the fire box.

If you're committed to moving forward yank the old stove so you can see what you have and start a new thread here about your plan and you'll get plenty of advice on required elements of a safe and efficient install.

 

[bholler]

It hasn't been cleaned but we have been burning for 2-3 months. We stopped burning it last night and are considering getting a new insert and lining it.

Now have to figure out what to buy.....

It should have been cleaned and inspected before you started using it. But you seem to be on the right track now.

 

[unimog1300]

It should have been cleaned and inspected before you started using it. But you seem to be on the right track now.

Thanks to all of you for the info.

We have decided to get a new insert and have a liner put in.

Are liners all the same? I see different thicknesses out there or it doesn't matter?

Rigid or flex ....any preference? If one is better then I want to go with that option.

Thanks again.

 

[bholler]

Thanks to all of you for the info.

We have decided to get a new insert and have a liner put in.

Are liners all the same? I see different thicknesses out there or it doesn't matter?

Rigid or flex ....any preference? If one is better then I want to go with that option.

Thanks again.

I prefer heavy wall flex. And it should be insulated

 

[unimog1300]

I prefer heavy wall flex. And it should be insulated

Thank you

 

[unimog1300]

Just an update on what's going on with the old insert.

Went to Hechlers in Troy MO to look at new inserts. They have a huge selection....at least to us they do(ck out their website or FB). We drove 2.5 hours one way to see them because nobody around Peoria Illinois carries BK or Buck, and we were going that direction for some other stuff so we just kept on driving. Pretty sure we will go with the BK Princess it seems. Like the burn time and the set it forget it ability. It won't be sole source of heat but can go a long way making a dent in our electric bill, will let the furnace pick up the slack. Six inch liner is also a plus, but have room for the 8" with some brick work in the damper area I guess if we go with the Buck 91.

Chimney sweep came by to take a look at what the current setup is. No issues other than he believes we will need a chemical strip of the creosote. They said it will make it look new inside. Nobody has pulled out the current insert to look yet but that was the initial feeling. Was not expecting that or the cost ($1800) to to do the chemical stripping or the time frame to get it done because of the temps right now. Said they needed 65* or better for a couple of days to do it which means March or April. Pretty much shoots any usage of a new insert for the next 2 or 3 months.

Was planning on doing a block off plate with Roxul myself after reading about them on this forum. Does the entire 25' of 13X13 flue tile need chemical stripping if there's a block off plate and insulation with the insulated liner? If not, the work could be done to strip the brick in the fireplace with the old insert out, and the temps are right for the process since it's indoors. Not looking to cut corners but what is actually needed to make it all work? Any other process besides chemical strip to remove the buildup?

With the chemical strip and costs of an install I think I'm looking to do the install myself. Even If I have to rent a lift for a day to get the liner in (25' tall and 12/12 pitch roof) I'm money ahead it seems.

Thanks for any suggestions you all might have.

Steve

 

[jatoxico]

BK is a nice stove. They function best when draft is within spec so check that chimney will not be too tall. Not a pro opinion but if it comes to it I wonder if it would be cheaper to remove the clay tile altogether than strip it. Certainly make installing the liner a whole lot easier. What size is the clay tile, can you pass an insulated liner thru it?