Fireplace Inserts Make Good Sense
Sometimes people come to us in our Sonoma store looking for a set of gas logs to add to their fireplace, because they tell me, “I’m tired of fussing with a dirty fire!” This is a summary of the conversation we invariably have. First, let’s get clear on what a fireplace insert actually is. A fireplace insert is a manufactured metal box which inserts into an existing pre-built fireplace, and typically creates much more warmth for the room than the inefficient wood burning system it is replacing.
So why, then, is an insert more efficient? Folks tell me “I feel the fire’s warmth when I stand in front of it!” “it bakes us out of the room!”
Fireplaces Give Warmth, Ambiance & Heating Source
Fire gives warmth in the same way the sun does – via something called ‘radiant heat’. The heat follows a line-of-sight path, and warms everything pointing at it by radiating heat that’s absorbed by objects in its path. Like the sun, if someone,like my wife, stands in front of you to be closer to the warmth, then you are in the shadow, and you no longer feel the warmth.
A fire needs a chimney, for all the toxic byproducts of combustion (a.k.a. ‘smoke’) will come into the room with you and smoke you out. A chimney which is drawing properly will take all that smoke out of the building.
A fire also needs oxygen or air to burn. Typically this air comes from the room the fire is in. An open fire in a fireplace uses a lot of air, and there is a large transfer of smoke and air from the room right up the chimney. This is where the inherent inefficiencies come into play – a whole lot of warm air goes up the chimney, and is replaced by cold air from outside the house.
Lastly, when the fire is not burning, the chimney provides an excellent pathway for warm air to escape from your house to outside. Additionally, on windy days, the chimney can ‘backdraft’, which means it flows in reverse direction – typically bringing in an unpleasant ‘smoky’ odor to the home.
Gas Log Sets versus Fireplace inserts
A gas log set has zero efficiency story to it. By law, a properly installed gas log set requires that the installer block the chimney flue in the ‘open’ position. This is so the log set does not inadvertently get used with the flue closed, poisoning everyone in the house with carbon monoxide. So the whole time it is off, warm air from the home is going up and out your home’s chimney, making your central heating system work that much harder to keep you warm.
A fireplace insert works by containing the fire in a sealed box, and frequently drawing air via a duct from outside directly to the firebox. Warm room air does not go into the firebox, up the chimney, and out of your house in an uncontrolled way like it does with an open fireplace. Inserts use a dedicated flue liner which is placed inside the existing chimney, sealing everything so outside air does not come down the chimney, and there is not an uncontrolled flow of ‘conditioned’ house up the chimney. Better inserts are designed with heat exchangers to wring as much heat out of the fire as possible.
The use of an insert’s own flue system seals the open chimney so room air does not flow up and out of it – keeping warmth in your house where it is needed.
Fireplace inserts Can Use Wood, Gas or Pellets
A quality wood inserts burn wood very efficiently. Wood burning inserts for sale today need to be EPA-rated to ensure they do not put too many particulates into the air. Regardless of how cleanly they burn, wood fires still are illegal to use on ‘Spare the Air’ days, as designated by the local Air Quality District of the state government.
Modern wood burning inserts meet the EPA 2020 particulates threshold rule, typically by the inclusion of a second-stage after-burn area and the addition of a catalytic combustor. Again, regardless of how cleanly the wood-burning insert burns, it is still illegal on very many days during the winter to use it.
- Pollute less than any type of wood or pellet insert
- Very realistic flame
- Radiate fantastic amounts of heat
- Are classified as ‘heating appliances’ by the EPA, and typically are highly efficient
- You don’t have to make a fire, you ‘turn it on’.
- Normally controlled via remote control, a wall switch, or a thermostat.
- Adjustable flame height
- Integrated blowers put even more hot air into the room.
- Do not need frequent chimney cleanings
- Direct-Vent flue system pulls combustion air from outside your house