Overfiring Insert

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

cpop

Member
Hearth Supporter
Sep 18, 2007
19
CT
Newbie here. I read in the manual about the dangers of overfiring my insert and that it will not be covered under warranty if I do so. Dumb question; how do I know if I over fire my stove? When I start a fire how long should I wait until closing the damper a bit? Is 30-40 minutes too long? Today, about 30 minutes after lighting the fire I heard a loud noise come from the stove, not sure if I heat it up to quickly. Any input from the more 'seasoned' burners here would be much appreciated.
 
Depending on the stove, usually the best guidance you will have is if you can put a thermometer on the stove. What stove make and model is this?

A loud noise from a new steel stove can happen as it warms up.
 
Yeah. Cute stunt the stove makers pull and it pisses me off no end that they don't tell what overfiring of their stove is. Rule of thumb for a steel stove is 700 degrees stove top temperature. Five to six hundred is a good target to shoot for for efficient burning. EPA or non-EPA stove. Most manuals say that if something is glowing then you are over-firing. Well that is around 1,100 degrees. Don't go there, don't do that.

They omit any temps to dodge warranty claims plain and simple. Easy to say "You over fired it.". And I invite them to get on the Forum and say otherwise and give specific temps for their stoves. They built'em. They test'em. Tell us about it.
 
Thanks guys. I have a Hampton hi300. The dealer did not recommend a temp gauge because he says there is no real good place to put one on this insert. Anyone out there have a hampton insert with a temp gauge?
 
I don't think I am over-firing, but this is what happens. I start a fire and leave damper in full open position for about 20-30 minutes. Then close half way for about 10-15, then 1/4 more. After about an hour or so in the baffles at the top look a bit red. Not Glowing red, but a red tinge to them. Not sure if that is just flame reflecting in the baffle or what. The stove is only half full and dampered down to 1/4 open position so can't believe that this is over firing. I'm concerned that I am not doing something right.
 
I have the same stove. I put one of those magnetic ones on the top of the shelf where the air blows out. If the temp is 225 to about 310 it is in the right zone for me. I don't go any higher than that. Not a perfect answer but best I can do. BTW I have had it for over a year and nothing is warped yet ;~) You could probably go higher but I am chicken and like it below 90 in my house!!! GOOD LUCK AND ENJOY!!!!
 
If the tubes up top are glowing that's normal. They need to be 1100F+ to burn secondary gasses so they will glow. They're stainless steel and designed to handle those temps. They even have insulation above them to make sure they get hot. The rest of your insert is not okay.

It's not too difficult to know you're overfiring an insert. I knew I was overfiring mine when the room with my insert was extremely hot compared to the rest of the house, there was a funny smell, parts inside the unit were glowing cherry red, and it was difficult to approach the unit I was blasted with so much heat. I'd started a fire with all oak, left the door open a crack to get it going and went to do something else and forgotten about it. Even my soapstone was glowing. Fortunately the blowers were helping it from overheating, my wife took care of that. She noticed it was putting out so much heat she could hardly tolerate it so she shut the blowers off and left it as it was. 20 minutes afterward the smell reaches me and I fly in and shut the door. I then yell at her sitting in the same room as it, didn't you notice it's glowing, the funny smell, that the door was ajar, and you can hardly go near it!? She said yup, that's why I shut the blowers off I was hot and I turned down the air but I don't think that air handle works when you leave the door open like that. She then went back to reading her magazine. I don't understand how she didn't know to SHUT THE DOOR or get me. She's also the one, I have a technique I push all the coals to the back and empty the ash sitting in the front each time I load up. I showed my wife, and asked her to do similar. I got home that evening and looked like she did it. I go to add more wood, and scoop out the ashes in front, open up the ash can to find it she'd taken a fire that had about 3 hours left and dumped the whole thing into the ash bucket. It was full of half burned full length wood splits. Anyway, it's not hard to know your insert is overfiring. Do what burntime did and get a stove-top thermometer. You won't know exactly but if you're usually around the 275F temps, and you look at it and it says 400F+ most likely something is up plus you usually have a smell.
 
Really appreciate the input Rhonemas. I think we have all been in that situation with our wives. I was really nervous last night about the baffles turning red and wife just didn't understand at all why I was so concerned. Don't want to destroy a 4000 investment. I'm going to get a thermometer to see what range I am in. I hear so many ppl on here saying rooms get in the 80's and 90's. I have had the insert running for 4 hours and house only moved from 66 to 69. I don't think it is my wood since I have tried cord wood and bio bricks to make sure. They installed a block off plate with and full stainless liner so I think the install is ok, unless they did not install the block off plate correctly or something.
 
Hi cpop,

I had the same problem with my insert when I first ran it. Ran it hot for many hours and wouldn't hardly even heat the room it was in very well. Installer talked me out of a 'lower' block off plate in the fireplace damper area. I installed a 'lower' block off plate and it made a HUGE difference. The block off plate should totally block off the damper area. The hole through the block off plate needs to be bigger for the liner to pass through. Do you have a 'lower' block off plate in the damper area of the fireplace? If so, I wonder if your installer closed the gap between the block off plate and liner?

Last year my wood wasn't totally dried/seasoned/cured. So far this year I'm noticing a big difference in the heat output and the ease of rekindling fires with properly dried wood.

Luke
 
Hi Scrounger,

My dealer also tried talking me out of a lower block off plate; however since I was reading this board I advised him I wanted one. I saw them come into the house with the block off plate, but then could not watch them install because I work from home and had some issues to take care of. I hope they installed it properly, but can't be sure. I don't want to pull the insert out because not sure how to do it exactly and don't want to break anything. The installer is coming out for a service call next week to look at another issue with damper control, maybe I will have him pull out the insert and have him show me how the block off plate is installed.

One quesiton I have always had though is how the block off plate can make that much of a difference? I can see with a regular stove on the hearth since the fireplace opening is still open to the room air, but with an insert the shroud is blocking room air from entering the fireplace opening.

Chris
 
Cpop that's normal. Inserts heat different than stoves, and you going from 64 to 69 after 4 hours is not that bad particularly your first year while you learn your unit. After the first year you'll probably be able to get your house from 64 to 69 in less time. Those people saying their room gets 80's+ have stoves. Stoves are excellent room heaters, and can heat the room they're in to greater temps than an insert, and do it much faster but don't heat the floor and it's extremeties as well or fast as an insert. A stove heats with radiant & convective energy. The radiant energy of a stove is a form of light, and can only be used in the area around the stove. The other type, convection is hot air which spreads around the room and other parts of ones house. An insert has very little radiant energy, it has a shroud around it and the amount of radiant energy it reduces by, is directly proportional to the gain in convection heat. So, an insert puts out a lot more hot air than a stove which spreads & moves around the house and doesn't stick around the room with the insert (unless it's closed off).

So, it's no problem for a stove to get the room it's in to 80F+ but the rest of the house won't be near as much and other rooms/extremeties in a house heated with a stove will be colder than those heated with an insert. An insert doesn't heat the room it's in, it heats the floor which takes time. Stoves are better room heaters or better when you come home to a cold house the room they're in will quickly be warm, inserts are better floor/house heaters and better at maintaining temp. I hope I explained it well. If you wanted a room to be 80F+, you probably would've been better with a stove. If your goal is to spread the heat around evenly, use it in other areas, or warm up your "floor" faster you're better with an insert. My insert forces all the air in my house heating it to 150-175F every 50 minutes then repeats, it heats my house like my stove never could and I hated the fact the area around my stove got to 80F+ it was way too hot for me. Now when the room with my insert warms up to 72F the rest of my house is also around 72F. My in-laws who are elderly, like a hot room that's 80F+ and like that their stove heats their room to those temps (but the rest of their house is not heated like my insert). To them, that's what they prefer. It's all in the eye of the beerholder which is better suited.

So, in summary the reason your insert is taking so long is because it's trying to heat up your entire floor not just the area around it. Mine is likewise.
 
Thanks so much for taking the time to write such a detailed reply Rhonemas. I prefer having the whole house heated versus one room 80+ as well. I just wanted to make sure everything was operating as it should since so many ppl report being blown out of the rooms and opening windows, doors, and such which I haven't had to do. Your explanation makes perfect sense. My dad has a stove and the room it is in gets really really hot, but the rooms on the other side of the house are cold.

Thanks again,
Chris
 
I was searching for something else, and ran into this thread, glad that I did. I too just got an insert and was wondering about over firing. I didn't get a thermometer, shop said that since it is an insert, there is really no place to put it. I went ahead and ordered a stove top thermometer.

My wife grew up in a home with three older wood stoves, and she has her own thoughts on everything and how the stove should be run. I'm trying to get across to her, that a good rolling flame on the top is a good thing on modern EPA stoves.

The other night I think I did over fire it when I loaded it before bed. I put in three good sized pieces of wood. Cranked open the vent to get a good flame going, and moved it way down before retiring. Thankfully, it was Monday Night Football, and I was still up. I smelled something acrid, came downstairs and it was very warm and smelly. Turned the blower onto high and closed down the vent all the way. The bars along the top were all glowing bright red.

I love the heat that my insert puts out, I've had similar experiences. It has been in the 20's at night, and 40's during the day the last few days. My electric heat is set at 69, and hasn't come on for 48 hours. I'll probably move that down some more, especially the morning setting since that is when the fire dies down and I have to rekindle. The house has been holding at about 72 with the stove going.
 
cpop said:
Hi Scrounger,

My dealer also tried talking me out of a lower block off plate; however since I was reading this board I advised him I wanted one. I saw them come into the house with the block off plate, but then could not watch them install because I work from home and had some issues to take care of. I hope they installed it properly, but can't be sure. I don't want to pull the insert out because not sure how to do it exactly and don't want to break anything. The installer is coming out for a service call next week to look at another issue with damper control, maybe I will have him pull out the insert and have him show me how the block off plate is installed.

One quesiton I have always had though is how the block off plate can make that much of a difference? I can see with a regular stove on the hearth since the fireplace opening is still open to the room air, but with an insert the shroud is blocking room air from entering the fireplace opening.

Chris

I think the major function of the damper block off plate is to trap the heat at the fire box level. Creating a more efficient use of the heat created. I included a pic of my after market damper block off so you would have a better Idea of what it looks like in place. The only thing missing from the picture is the rock-wool I stuffed between the liner and the block plate after the insert was in the right spot. hope that helps.
 

Attachments

  • [Hearth.com] Overfiring Insert
    Hampton Install027resz.webp
    17.7 KB · Views: 381
I had a really nice harmon woodstove. I had been burning wood for a long time and I grew up with woodstoves. One day i fired up the stove with nice seasoned hard wood. The stove turned bright red and so did the black pipe. I thought I was going to burn down the house. That incident scared me so bad that I sold that woodstove and switched to pellets. Sometimes I miss burning wood. You had to be there.
 
I remember my dad doing that more then once in my youth. We had a free standing stove with about 4 to 5 ft of exposed pipe. There was a short run of pipe thru the atic and then it was routed thru an old chimeny on the roof. The damper would get so hot you couldn't touch it and the pipe would glow red all the way to the ceiling. (and beyond) It always over 100 degrees in the house and we would have all the windows and doors open trying to cool the place off. Those were the good old days! :lol:
 
Status
Not open for further replies.