Brick heat battery for insert?

[PlayWithFire]

I just finished installing some insulation and a block-off plate inside my fireplace above my insert. I noticed that there is about 8 inches between the top of my insert and the block of plate.

What do you think of this idea? Stack some spare bricks on top of my insert so that they can work similar to the Soap Stone on a soap stone stove. Absorb the temp spikes on a fresh load and extend even heat as the load burns down. Seems like this may work. The only problem is, these little heat batteries will be behind my cast iron face plate rather than in the room.

Will this bring any benefit? Or is it better to just get the heat out of the fireplace and into the room as fast as possible.

I have a Hampton HI300.

Thanks!

 

[Jags]

You will recognize very little return on that. First - if you do the math, the added mass isn't really storing that much energy and second - they are behind the face plate.
Without some pretty fancy tools I doubt that you would be able to measure any difference in room heat with/without the bricks.

 

[PlayWithFire]

Jags, Thanks for the reply. I'm sure you are probably right.

The next question... Will I get more heat with the top part of the case iron surround off? This way the heat from the top of the stove and 8" of liner would be exposed rather than covered with cast iron.

I would expect this is again difficult to measure. And who really wants to leave the pretty enameled surround off? Yet I would expect more heat in the room. thoughts?

 

[Jags]

More than likely, you are playing with tiny percentages. Run the unit as designed using a fan if needed. It should do a nice job for you. The Hampton is a quality stove. If you want to eek out the most btus that you can make sure that all of the controllable components are accounted for. Properly dry fuel, Proper draft, proper operating temps....etc. Thats the kind of stuff that can really make your stove a performance machine.

 

[firefighterjake]

As Jags said . . . adding brick as a heat sink is a nice idea . . . but the gain isn't worth it.

How do I know? Real life experiment.

Added a soapstone slab on top of my Oslo . . . sticks up a quarter inch. Gets plenty warm, but there just isn't enough of it. Now if I had an entire stove made out of soapstone or the stove was surrounded by soapstone . . . maybe. But even that big ol' slab of soapstone doesn't radiate off much heat once the fire goes out . . . it cools down at about the same time the big ol' (and much bigger) hunk of cast iron cools down. That said . . . I still leave the soapstone on . . . keeps my potpourri from burning up too quickly and is kinda pretty.

 

[velvetfoot]

You want to take off the cast iron top? Oh, the humanity.

 

[DougA]

The added mass will decrease the heat in the room at the beginning (by a tiny, tiny bit) as it absorbs heat and give off that heat at the end of the burn. Wood provides X amount of BTU. Adding mass such as bricks or soapstone can't change that number, other than shifting the time frame of when you feel the heat. Simple physics.

It's the same as a 10 hr. burn vs. a 20 hr. burn. The BTU output is the same in total, just spread over a longer time period. Of course, then there's the human factor that involves the brain compensating for the extra money you paid for a 20 hr. burn stove.

 

[Grisu]

Is that fireplace on an interior or exterior wall?

 

[PlayWithFire]

You want to take off the cast iron top? Oh, the humanity.

It was more of a theoretical question

Is that fireplace on an interior or exterior wall?

Exterior. I did add some insulation behind the stove and covered with metal plate.

 

[Grisu]

Exterior. I did add some insulation behind the stove and covered with metal plate.

That's great. You really did think of everything. I would just light some fires in the insert and see how it goes. Looks like you will stay warm this winter.

 

[PlayWithFire]

That's great. You really did think of everything.

With experts like you available, it's easy to think of everything

https://www.hearth.com/talk/threads...n-efficiency-be-improved.127389/#post-1713809

 

[HotCoals]

The added mass will decrease the heat in the room at the beginning (by a tiny, tiny bit) as it absorbs heat and give off that heat at the end of the burn. Wood provides X amount of BTU. Adding mass such as bricks or soapstone can't change that number, other than shifting the time frame of when you feel the heat. Simple physics.

It's the same as a 10 hr. burn vs. a 20 hr. burn. The BTU output is the same in total, just spread over a longer time period. Of course, then there's the human factor that involves the brain compensating for the extra money you paid for a 20 hr. burn stove.

I agree with what you said 100% except for the bold.

Burning lower and longer can save wood because you're not heating your house up over and beyond what it it needs to be.
I'd rather keep my house a constant 72f in the winter instead of big peaks and valleys. It's also more efficient not to have to load and setup the burn 3 or 4 times a day.

 

[mellow]

I saw most of my gains when I insulated the firebox behind the insert, on an exterior chimney it really makes a difference. I have tried running mine with the shroud off and my burn times dropped due to cooling the firebox too much, it was better to leave it in the insulated cocoon I built for it.

 

[pastera]

Want an immediate boost? Clean your blower out regularly. It only takes a small amount of dust to wreck the efficiency of the fan blades

 

[Enzo's Dad]

I have the hampton hi300 in the next town over from you. It works pretty awesome with the blower moving the heat as designed. I have a steel block off plate with roxul above. I have found it all comes down to the fuel. I cant really run my stove yet, It makes the living room too hot temps have to be in the 30's to justify running it.