stove won't get very hot

[turbotom1052]

Thanks to the many voices here on this forum I've managed a clean and safe install of my new to me, Hearthstone Heritage. Ive begun burning regularly after a couple of quick break in fires and am disappointed in the heat output of the stove. It should be mentioned that my wood is marginal in its moisture content, with most splits, after a resplit and center measurement coming in at an overall average of 20 to 23 percent moisture. With this less than ideal scenario I should also mention that I've, as per suggestions here purchased some biobricks to help my marginal wood out.
The problem I'm having is that even with 3 to 4 biobricks added to the firebox I can't seem to get the stovetop temps much above 300f. as measured by a Rutland magnetic stovetop thermometer placed as close to the center of the stove as possible without actually placing it on the top steel block off plate.
It should be noted that Ive only been able to see the very back row of secondary tubes outputting any flame and also that when I go outside the chimney is outputting NO visible smoke which leads me to believe that the wood is, at the very least burning completely. It should also be noted that even when I fill the firebox with ONLY biobricks the temps are still hard pressed to exceed 300f.
Is it my wood? Is it the fact that only the rear secondary tube is outputting flame? Or could it be a poor draft? The chimney is over 20 feet of insulted 6 inch stainless flex liner. The firebox fills with plenty of flame and on these not so cold New England nights the output is plenty to keep the Propane furnace from going on. Any input is greatly appreciated.

 

[Ash]

Sounds like your wood is still a little wet and your draft might not be so great but should improve with cooler temperatures. Your secondaries should light off when your stove gets a little hotter. Mine don't start going good until stoves are 450 or higher. As for the bio bricks, I have never used them but from what I read on here sounds like they are tough to get going good without a nice coal bed.

 

[kennyp2339]

We need a little more basic info, how tall is your chimney, what type of chimney system are you using, where is the stove in relation to your house, what type of house (newer & tight) (older with drafts), does the stove have a oak?
The chimney is the engine that drives the stove, if you have poor draft (good test is when you open your door and get smoke spillage) you are not getting the air into the stove to feed the fire. There are many possible solutions to this, but before giving any tips or advice we need to know what were dealing with.
Also the wood, yes its a little on the wet side, but it doesn't sound to terrible, especially if your using with bio bricks, I used some bio bricks last year and 3 or 4 together put out some good heat, Using the process of elimination I would lean towards the wood supply not being the main factor with your stove.

 

[Highbeam]

I burned a heritage for a long time on a 13 foot chimney. I have burned wet wood and good wood.

First, it takes forever for this stove to warm up but you are rewarded on the back end with a slow to cool down stove. Be patient.

Your splits are probably much too large. Measured in the longest dimension, your splits should be 3-5 inches across. That's with dry wood. With wet wood you need it even smaller.

With wet wood, it will burn slower with less secondary activity until all of the sudden it dries out and takes off. Don't let it get away from you. Keep an eye on it with wet wood. The redline temp for the heritage was listed in the manual. If I recall it was 550 or maybe 600. Don't go above that or stones could crack.

I tried the biobricks in the heritage and it is very easy to get a runaway. Be careful with those things, they are hard to control.

Your chimney, does it have a screen cap? Are you certain that it is totally clear? I would plug that stupid screen up so often that I removed it. It is now optional from duravent and my newest chimney was ordered without it. A filter on a chimney is not wise in my experience.

Are you operating the thing on full throttle all the time? As the stove heats up, you will want to reduce that air setting to encourage the secondary combustion, higher stove temps, and high efficiency. With wet wood you will need higher throttle settings but with your chimney it is very likely that you'll need to run at 0% throttle once the fuel is really rocking.

Lastly, your thermometer might not be dependable. Do you have another you can use or a way to test the one you have.

 

[turbotom1052]

We need a little more basic info, how tall is your chimney, what type of chimney system are you using, where is the stove in relation to your house, what type of house (newer & tight) (older with drafts), does the stove have a oak?

House is an old post and beam farmhouse with cathedral ceilings in the main room where the stove is. In the chimney I've installed a 6 inch insulated flex liner, a tad over 20 feet high, with a pretty much straight up run to a rain cap with no screen installed. The chimney is inside of an exterior wall with a poorly insulated addition between the chimney and the great outdoors. The stove has no oak as i figured the home to be not at all tight due to old construction. Im not leaning as much towards my woods mc as even when burning ONLY biobricks the stove won't exceed 300 to 325f. If in fact it takes over 400f. to light off all the secondaries then perhaps there is hope when the temps drop a bit and pull a stronger draft. Are the Rutland stovetop thermometers notoriously inaccurate? My goal is to purchase an IR thermometer this season to more accurately monitor temps.

 

[Highbeam]

When you are failing to hit even 400 on the stovetop is the stove intake setting at full high?

 

[kennyp2339]

Does smoke roll out the door when its opened?

 

[DougA]

On my Hearthstone, the magnetic thermometer is not very useful. You're measuring soapstone or cast iron, neither are good for a magnetic. I find soapstone always feels less hot to the touch than cast, even when the IR gun gives me identical readings - hence one of the big advantages of soapstone. I use an IR gun and a digital flue thermometer for accuracy. The IR gun readings can easily be 100 variation, depending upon where you measure it on the top alone. As Highbeam posted, it does take awhile to get a soapstone up to temp but it stays warm for so much longer.

Still, you should be able to get that stove well above what you are currently. Although mine is much larger, I can't get hot temps until I have the stove filled - I mean FILLED - with wood. 20 to 23% with biobricks in the mix should be fine but you still need a roaring fire before you begin to turn it down.
Another way I learned to get a fast, hot fire on a Hearthstone from this forum is to leave the door open a crack when you are getting your fire going. The draft will suck the door shut once it's roaring, then make sure it's latched securely.

See if any of that helps.

 

[begreen]

Yes, some stove thermometers including Rutlands can be inaccurate.

 

[turbotom1052]

When you are failing to hit even 400 on the stovetop is the stove intake setting at full high?

I've tried various primary air settings to include full high in an attempt to get temps up.

 

[Highbeam]

You don't have an OAK connected so have you tried leaving a window slightly open to allow air to enter the room? Is your stove window sooting up?

 

[turbotom1052]

Does smoke roll out the door when its opened?

When you are failing to hit even 400 on the stovetop is the stove intake setting at full high?

I've tried various primary air settings to include full high in an attempt at getting stove temps up. Ive tried smaller wood loads and full wood loads. Ive gotten it hot enough to light off the back row of secondaries by allowing a firebox full of good self sustaining flame to fill the entire firebox and then turning down primary air in hopes of lighting off the secondaries, but only the back secondary tube will light off.

 

[turbotom1052]

You don't have an OAK connected so have you tried leaving a window slightly open to allow air to enter the room? Is your stove window sooting up?

stove window will only soot up when i turn the primary way down for a long overnight burn. Don't know if it matters but there is no visible smoke coming out of my chimney so I'm guessing that I'm getting at least some secondary combustion.

 

[Highbeam]

You don't need secondary combustion for clear stove emissions. Many old smoke dragons could be burned cleanly despite no secondary system.

If you are getting sooty glass on a 20 foot stack (Assuming it's clear and the stove has plenty of air available) then you have wet wood. Chop it smaller and stack it with plenty of gaps. Think log cabin. I suspect much more than 23% moisture.

 

[kennyp2339]

When the stove is lit and burning for more than 30min, what color is coming out the chimney cap - Blue / dark smoke - un-burnt fuel, white whispy smoke - steam from wet wood.

 

[turbotom1052]

You don't need secondary combustion for clear stove emissions. Many old smoke dragons could be burned cleanly despite no secondary system.

If you are getting sooty glass on a 20 foot stack (Assuming it's clear and the stove has plenty of air available) then you have wet wood. Chop it smaller and stack it with plenty of gaps. Think log cabin. I suspect much more than 23% moisture.

my newly purchased moisture meter reads between 20 and 23 percent in the center of numerous freshly split and read pieces. If my wood was as you say "much more than 20 percent" wouldn't I then be billowing smoke from the chimney?

 

[turbotom1052]

When the stove is lit and burning for more than 30min, what color is coming out the chimney cap - Blue / dark smoke - un-burnt fuel, white whispy smoke - steam from wet wood.

the only thing I see coming from the chimney cap after the stove has been burning for a bit is heat waves. NO smoke of any color.

 

[Highbeam]

my newly purchased moisture meter reads between 20 and 23 percent in the center of numerous freshly split and read pieces. If my wood was as you say "much more than 20 percent" wouldn't I then be billowing smoke from the chimney?

Not if you burn it right. It will be slow to get going and slow to be smoke free but eventually you will dry it out and it will burn. Sooner and hotter if you use small splits stacked loosely.

 

[Smoked]

I am trying to burn some black cherry during the shoulder seasoned and it is hard to get going. A medium load of dry oak and I get 450 in an hour. The one I am burning right now is new and I am having to relearn a bit. side door open a little longer (Make sure it is closed when closed) and more primary air longer. The oak gave me good secondary burn but the cherry was a struggle and it is 2+ years CSS. What species of wood are you burning? I would try another thermometer too!

 

[DougA]

Not to start an argument but I'm burning black cherry right this minute and it is awesome to get started.

 

[BradleyW]

I think you are shutting the stove down too quickly. With less than ideal draft and less than ideal wood, you might be in a situation where a start-up fire never really warrants shutting the stove down at all, or maybe shutting down 25-33% at best. Many of my fires or these cool nights are like that. When draft improves with cooler temps and you start burning more and are putting splits down on a hot bed of coals you will probably find your fires more closely match a "textbook" fire. Are these shoulder-season nights the most efficient time to burn? No. Do I do it anyway because I enjoy building fires? Yes.

 

[turbotom1052]

I am trying to burn some black cherry during the shoulder seasoned and it is hard to get going. A medium load of dry oak and I get 450 in an hour. The one I am burning right now is new and I am having to relearn a bit. side door open a little longer (Make sure it is closed when closed) and more primary air longer. The oak gave me good secondary burn but the cherry was a struggle and it is 2+ years CSS. What species of wood are you burning? I would try another thermometer too!

I've been hand picking mostly ash splits as they are the lowest reading moisture. Im leaning towards my wood NOT being the problem as even when I burn biobricks alone the stove won't get above 325 degrees as read on my stovetop thermometer. Ive been to a couple of retailers looking for an infrared thermometer but all I'm seeing is units that max out at around 600f. Id like to be able to also use it in an automotive capacity and was hoping to get one with a higher heat range. Are the stovetop thermometers that are made for soapstone more accurate than a magnetic rutland thermometer?

 

[Smoked]

Not to start an argument but I'm burning black cherry right this minute and it is awesome to get started.

Maybe I need to save mine for better burnin weather with better draft

 

[Smoked]

I don't think anyone asked this, is the baffle sitting nice an flush down on the tubes and tight all the way to the back of the frame? It should be tied and maybe even glued down but if it shifted forward and you have a gap in the rear, you could be losing some heat there.

 

[brad wilton]

Could it be possible that some packing material is blocking the air inlet ?