Getting heat out of the fireplace

[Fried Chicken]

Friends overseas ask me what America is like. I don't think I've found a better summation than "we have fireplaces designed to NOT heat the home".
Here's mine:


Now I'm looking at options to rectify this since I removed the fake logs and natural gas rod, and there are options abound at all sorts of different pricepoints.
I don't want an insert.

These guys make a tube design that IMO marries a decent aesthetic w/the promise of high heat output. The price is about half without the ugly blower and manifold. It's still a hefty chunk of change, and the it has vudu vibes about it. There are other offerings online, all seemingly from different levels of professional redneck.

More traditional, affordable with more aesthetics but with potentially less heat are these vertical stacks along with a giant pane of metal in the back.

Anyone with experience using these products?

 

[SS396driver]

First I would have professional look at your fireplace and flue . If it’s one of the newer zero clearance gas units it’s not suited for burning wood

 

[SS396driver]

I should add that if your good to go with wood then a good quality set of glass doors . Keeps the fireplace from sucking out all the heated air from the room . Fireplaces are nice but as it goes out no heat produced and now it’s sucking huge amounts of heated air out of the house

 

[Fried Chicken]

First I would have professional look at your fireplace and flue . If it’s one of the newer zero clearance gas units it’s not suited for burning wood

No issues there, it's a masonry fireplace built in 1996

I should add that if your good to go with wood then a good quality set of glass doors . Keeps the fireplace from sucking out all the heated air from the room . Fireplaces are nice but as it goes out no heat produced and now it’s sucking huge amounts of heated air out of the house

It's not a problem. We don't have serious heating needs in Texas, and I'm mostly interested in having a nice crackling fireplace. That said, I'm still not interested in merely heating the chimney.

 

[SS396driver]

You said no insert so your left with having only a few options . My parents had one of those half circle pipe things in the fireplace in the 70s . Worked ok but they did changed to glass doors and the heat was much more effective in that room . The nice things about a good quality set is you can close them while the fire is burning so you have a quasi insert . And you can leave them open to have a nice crackling fire then close them when you leave the room or go to bed . An open fireplace will draw a lot of heat out of the house after the fire dies .

 

[Fried Chicken]

You said no insert so your left with having only a few options . My parents had one of those half circle pipe things in the fireplace in the 70s . Worked ok but they did changed to glass doors and the heat was much more effective in that room . The nice things about a good quality set is you can close them while the fire is burning so you have a quasi insert . And you can leave them open to have a nice crackling fire then close them when you leave the room or go to bed . An open fireplace will draw a lot of heat out of the house after the fire dies .

I'll look into the glass doors. I thought they could only be installed along with an insert.
They would still benefit from one of the vertical firewood racks? I have heard the new glass doors are incredible for what they're capable of

 

[stihlaficionado]

Friends overseas ask me what America is like. I don't think I've found a better summation than "we have fireplaces designed to NOT heat the home".
Here's mine:

View attachment 1209843
Now I'm looking at options to rectify this since I removed the fake logs and natural gas rod, and there are options abound at all sorts of different pricepoints.
I don't want an insert.

These guys make a tube design that IMO marries a decent aesthetic w/the promise of high heat output. The price is about half without the ugly blower and manifold. It's still a hefty chunk of change, and the it has vudu vibes about it. There are other offerings online, all seemingly from different levels of professional redneck.

More traditional, affordable with more aesthetics but with potentially less heat are these vertical stacks along with a giant pane of metal in the back.

Anyone with experience using these products?

We had a Preway fireplace many moons ago, before I put in a ZC high efficiency fireplace
I used a cast iron fireback, that sat just behind the grate. Once hot it threw out a decent amount of heat.

This is what a fireback looks like

You'll need to upgrade to an insert to get good heat that lasts.
ZC's are not meant to go into masonry fireplaces. They offer versatility, usually 2-3 inches standoff from framing. It's like having a UL 127 casing around a fireplace.

 

[Hermio]

If you can accept a quiet blower, there are manufacturers that make forced air exchangers that go under glass doors and get heat from the coals, which are hotter than the flames. When we had a normal fireplace, we installed one and glass doors, and it put out a lot of heat. One brand is Airculator. Here is a link to another: https://hastyheat.com/collections/2...changer-works-with-standard-glass-door-frames
Now we have a Tulikivi unit, which is more efficient than any woodstove or normal fireplace, but it costs $$$$ and must be built into the house. (Ours weighs 9000#)

 

[muddy42]

First of all you need to recognise that open fires are always less efficient than a stove. Stoves reburn the gasses and extract more heat from the gasses before they go up the chimney. So all things being equal open fires need more fuel. I only say this because I've had people raise the lack of heat complaint about open fires before, mostly when they have to buy there own wood. If you collect it yourself this is less of an issue.

Then modern builders often don't get the dynamics right. I can't see the flue but maybe it could be too wide for the size of the fireplace opening? The fireplace looks fairly deep. You could try bringing the fire forward to radiate more heat into the room. Plus that fireguard looks like overkill and will be blocking a lot of heat.

 

[Hermio]

First of all you need to recognise that open fires are always less efficient than a stove. Stoves reburn the gasses and extract more heat from the gasses before they go up the chimney. So all things being equal open fires need more fuel. I only say this because I've had people raise the lack of heat complaint about open fires before, mostly when they have to buy there own wood. If you collect it yourself this is less of an issue.

Then modern builders often don't get the dynamics right. I can't see the flue but maybe it could be too wide for the size of the fireplace opening? The fireplace looks fairly deep. You could try bringing the fire forward to radiate more heat into the room. Plus that fireguard looks like overkill and will be blocking a lot of heat.

Most open fireplaces actually have negative efficiency. Glass doors help a lot, but without a heat exchanger, they will still not provide all that much heat.

 

[muddy42]

Most open fireplaces actually have negative efficiency. Glass doors help a lot, but without a heat exchanger, they will still not provide all that much heat.

I'm never really sure how negative efficiency could be measured? Does that mean if I light a fire it sucks in warm air from elsewhere in the house and sends it up the chimney?

I live in a Victorian single glazed house, designed to be heated by wood - wood biomass boiler, stoves or open fires. When I light an open fire (and I do most nights) the important thing to me is the sitting room gets very hot very quickly and looks nice. If this makes other areas of the house cooler I'm not sure I care that much. My wood is free.

 

[Hermio]

I'm never really sure how negative efficiency could be measured? Does that mean if I light a fire it sucks in warm air from elsewhere in the house and sends it up the chimney?

I live in a Victorian single glazed house, designed to be heated by wood - wood biomass boiler, stoves or open fires. When I light an open fire (and I do most nights) the important thing to me is the sitting room gets very hot very quickly and looks nice. If this makes other areas of the house cooler I'm not sure I care that much. My wood is free.

That is exactly what it means. An open fireplace moves a huge amount of air up the chimney. This is especially true if the firebox is deep. In some older homes, the firebox was shallow and the fire was built very close to the front of the fireplace. This was much more efficient, as it allowed the radiant heat to get into the room. But only radiant heat gets out. With woodstoves and heat exchange fireplaces, heat from the flames and/or coals is also partially recovered.

 

[telecasterfool]

Before I installed a wood stove, I used my fireplace quite a bit and tried to get the most heat from it. I purchased four items from Grate Wall of Fire. A 3/4" fireback for the back, two 1/2" firebacks for the angled sides, and one of their fireplace grates. I also removed the screen, which blocks a lot of heat. After starting the fire, it would take about an hour for the entire fireplace to get hot and start kicking out the heat. It would make the room it was in very warm, and the rest of the house very cold, as air is sucked up the chimney. Ask questions if you want more info.

 

[Fried Chicken]

Before I installed a wood stove, I used my fireplace quite a bit and tried to get the most heat from it. I purchased four items from Grate Wall of Fire. A 3/4" fireback for the back, two 1/2" firebacks for the angled sides, and one of their fireplace grates. I also removed the screen, which blocks a lot of heat. After starting the fire, it would take about an hour for the entire fireplace to get hot and start kicking out the heat. It would make the room it was in very warm, and the rest of the house very cold, as air is sucked up the chimney. Ask questions if you want more info.

Did the grate wall of fire and firebacks make much of a difference?

 

[Fried Chicken]

I've done a bit more research and slept on the thought.

I don't like the idea of an insert when there's already a perfectly good fireplace. It's a very space inefficient solution.

I do like the idea of glass doors with a blower/heat exchanger of some sort. Unfortunately the only solutions I've find (like this one) similar to the inserts throw a lot of otherwise usable space away. It also looks like a nightmare to clean.

I found a product that kind of looks like it might achieve this

 

[telecasterfool]

Did the grate wall of fire and firebacks make much of a difference?

Yes. I was happy I purchased both the grate and the fireback. The fireplace was still very inefficient (lots of air up the chimney) but threw a lot of heat forward. Someone else may be able to comment on using doors - that may keep warm air from rushing up the chimney. I used my fireplace wide open.

 

[J D]

I've been told adding an air source can make a significant difference. A friend of mine did this by literally boring holes through the floor in front of his fireplace & he swears by it

 

[Billhook]

I built a Rumford designed fireplace from I think about 1790. It has a shallow back wall revealing a large area to reflect heat out. It also has a full width throat with a smoke shelf behind and an adjustable flap to help prevent downdraught and also to stop heat escaping if fully closed when perhaps you are using other heat sources
My old fashioned builder gave me an earful saying he had never seen anything like it and it would never work, but in the Winter I caught him and his mate warming themselves when they should have been on the roof tiling! “ Well I never would have believed it!” They said!

I also put two four inch diameter pipes feeding air from outside to the sides of the fireplace so the air was not pulled under the doors or through gaps in windows
I put a length of bar from the bottom of the flap over the throat so that I could adjust it from outside with a screw thread.
A pair of mesh doors finished the job over 40 years ago so that it could be safely left unattended or the room shielded if it became too hot

https://images.app.goo.gl/2pxecQnbbyEogX7v6

 

[Billhook]

It is a hot as my wood stoves, an Aarrow and a Danish Aduro and has never smoked even when lighting. Behind the smoke shelf I installed a hinged metal door which can be opened and the chimney swept with the throat flap firmly shut and the soot going outside

 

[Blue Oaks]

I had one of those blower manifold setups when I bought my house. It quickly oxidized and I threw it away. If you get one, get a stainless steel one so it lasts. Mine worked quite well until it didn't.