How Does A Fireplace Insert Work?
There’s nothing quite like the look of a roaring fire in a fireplace. In different circumstances, it can be reflective, relaxing, romantic, festive – you name it, a fire in a fireplace can enhance any mood.
It can even, if you’re standing, or sitting, or lying fairly close to it, enhance the mood of comfort and warmth.
If you’re a fair way away from it in a bigger room though – nnnno. Looks fantastic, but as far as an efficient source of heat is concerned, it’s not your best friend.
The Hearth, Patio & Barbecue Association (because you knew there’d be one), rates older fireplaces particularly as having just a 5% efficiency rating when it comes to heating a room, because for instance, older stone fireplaces actually absorb the heat of the fire they surround, rather than helping to push that heat out into the room.
That more or less reduces a fire in a fireplace to a visual treat only, unless you’re almost entirely on top of it.
But there’s something fundamentally wrong about that, surely. It’s a fire, after all – shouldn’t it be able to heat a room as a matter of first principles?
You’d think so. But to do that, a standard fireplace needs a helping hand. Some people fit fans that act as fireplace blowers, sucking in colder air from the room, running it through the firebox, and then pumping it back out in the room, to start convection currents of warmer air.
And other people add fireplace inserts, that can boost the efficiency of a fireplace as a heat source from 5% all the way up to 50%.
What is a fireplace insert?
At its simplest level, a fireplace insert is a fireproof box, surrounded by steel or cast iron and with a front made of insulated glass. You insert the box around and over your fire, so that, for a start, you don’t lose most of the heat up a chimney, and the heat is not absorbed by the stone of a fireplace (or whatever other material your fireplace is made of).
Effectively, a fireplace insert turns your fire into a closed combustion system. The steel or cast iron help to trap the heat, and by reducing the amount of freedom the heat has, it forces it back out into the room in a much more directed way than a fire in a fireplace without an insert ever will.
You can use a fireplace insert with most types of fires, because the principle of trapping and redirecting the heat, rather than absorbing it or letting it escape through non-productive channels is the same irrespective of the source of the fire.
You can also add a fan to the insert to turn it into a blower, which will give you the best of both worlds – a vastly increased radiant heat productivity in the room, and a convection current of hot air that will, over time, heat up all the air in the place, both without incurring much additional cost.
Both fireplace inserts and the optional fireplace blower are ways of maximizing the effect of the heat of the fire to warm up more of the room than the fire would if it were merely contained in a standard fireplace.
That’s especially the case if the fireplace has a chimney that would otherwise vent a lot of the heat into the outside world. Hot air rises, of course, which means the first natural direction of travel for the hot air above a fire is upward, rather than out into the room.
By simply encasing the fire in a fireproof box, your fireplace insert has the same sort of effect as braces have on teeth. By restricting how they can grow, you achieve the result you want. Likewise, by restraining the how heat can escape (for which, read “be lost like throwing dollar bills up the chimney”), the fireplace insert vastly increases the effectiveness of the heat in the room.
So it can save me money?
Yes. Yes, it can. Quite how much money will depend on the fuel source you use, the frequency with which you light the fire, and the length of time you spend in the room with the fire working. Essentially though, a simple comparison between the 5% efficiency of a fireplace fire without an insert and the up-to-50% heat efficiency of the same fire with an insert has got to tell you something.
Higher heat efficiency equals more effective heat use, which in turn translates to less money spent heating the air above a chimney, and a higher percentage of the same cash spent heating the room with the people in it.
But won’t I be losing the charm of the fire?That pretty much depends on you. The fire will still be visible through the tempered glass of the fireplace insert. It depends whether the charm for you includes seeing the flame lick up into the air, or whether you can get the charm you need from seeing them lick the roof of the box in which the fire is contained.
If you’re all about the long licks, then sure, you’re not going to get the full-on charm of a free fire. But you’re also not going to be more or less throwing dollar bills on that same fire for the picturesque effect, and in addition, you’re not going to still be shivering cold in the same room as a blazing fire – an effect which feels like a particular effrontery, somehow.
In compensation for the loss of the long lick look though, you open yourself up to lots of new decorating options, where previously the free-form fire would have hampered you - glass rocks, bronze doors, stones, log sets, you name it, and with the fire safely contained, the decorative world is your oyster.
Fireplace inserts are a viable option irrespective of the type of fire you have, and they can both make your room warmer and save you money in the process. There will be people who can never get on with them for their ‘caging’ of the flames. But for everyone else, they’re elegant, economical, and effective ways to get the maximum heat out of your fire.