FAQ Page

EPA certified stoves produce up to 90% less smoke emissions and burn up to two thirds less wood when compared to a traditional air tight stove.

No and yes. Stove efficiency is directly related to a very complicated combustion and heat exchange engineering balance. A stove needs the correct fuel to oxygen ratio, a turbulent combustion area, and a minimum pot temperature to combust efficiently. All natural draft stoves must use heat to generate draft inside the chimney and to exhaust the moisture in the wood. Excessive heat exchange to the room will cause the stove’s pot temperature to drop, reducing combustion and heating efficiency. Insufficient heat exchange to the room will cause the stove to send excessive heat up the chimney, reducing heating efficiency. An excellent stove will have a net efficiency of about 70% and an LHV (using moisture-less wood) efficiency of about 82%. Excessive efficiency claims should be disregarded.

Not likely. With premium engineering or a lot of luck it is possible. Wood burning heater efficiency is directly related to a very complicated combustion control and heat exchange engineering balance. A wood burning heater needs the correct fuel to oxygen ratio, a turbulent combustion area, and a minimum pot temperature to combust efficiently. All natural draft wood burning heaters must use heat to generate draft inside the chimney and to exhaust the moisture in the wood. Excessive heat exchange to the room will cause the heater’s pot temperature to drop, reducing combustion and heating efficiency. Insufficient heat exchange to the room will cause the heater to send excessive heat up the chimney, reducing heating efficiency. An excellent wood burning heater will have a net efficiency of about 70% and an LHV (using moistureless wood) efficiency of about 82%. Excessive efficiency claims should be disregarded.

Straight in loading is more convenient. The firewood settles against the two sides of the firebox instead of against the back of the firebox and the front loading door. You do not need to reach as deep into a hot firebox, it is easier to fill the firebox right full, and easier to select the perfect size for the last couple logs. Air is easily able to travel between the logs to the back of the stove, helping to quickly pre-heat the wood and remove the moisture. Straight in loading is best for maximum efficiency, high heat output, full load fires. On some occasions sideways loading may be preferred. The wood will act as a deflector slowing combustion, preventing air from reaching the back of the firebox early in the fire, but sending that air straight up the chimney. Sideways loading is best for lower heat output fires, but will have slightly lower efficiency.

All stoves certified to the ULC-S627 or former equivalent CSA standard will have left the factory with a rating plate attached to the stove and a certified installation manual. The required clearances are unique to each model and can be found in either the manual or on the stove label, except for very old certified units where the clearances were only printed in the manual. Uncertified stoves must use the applicable universal clearances found in the CSA B365 Installation Code.

Despite popular belief, the science says no. In simple theory they are equal because: whether the air passes through the living area or not, the combustion air begins outside at outside temperature, passes through the stove, and is exhausted to the outdoors at the chimney temperature. However, the location of the outside air hood can greatly affect the efficiency. In actual installations outside air hoods are down close to the ground where the air pressure is greatly affected by changing winds. If the hood is on the leeward side of the house it will increase restriction in the air intake and therefore reduce chimney efficiency and eventually combustion efficiency. If the hood is on the windward side it will pressurize the intake, cause over-firing, and therefore reduce heat exchange efficiency (yes it is theoretically possible to use a naturally pressurized air intake system to increase the overall efficiency of a wood combustion system but it is not practical).

No. The stove draws the whole mixture of room air into the air intake, not just the oxygen. The stove exhausts the products of combustion to the outdoors through the chimney and does not reduce the oxygen percentage in the home. Only a non-vented combustion appliance will cause oxygen depletion.

No. Back drafting is simply smoke moving from a high pressure zone to a low pressure zone. It is caused by a poor chimney/stove pipe configuration, restriction in the chimney/stove pipe, or depressurization of the home. Direct connect outside air does not affect any of these causes. High efficiency stoves exhaust a small amount of air and are not able to cause significant home depressurization. Back drafting can be prevented by choosing a good chimney/stove pipe configuration, keeping the chimney/stove pipe clean and preventing home depressurization.

There are many possible causes. The most common cause is mechanical ventilation such as clothes dryers, bathroom/kitchen exhaust fans, an improperly adjusted HRV, or even dirty filters on an HRV. Another common cause is “stack effect”, where the entire home becomes a chimney. It is caused by having more air leakage in the upper portion of the home than the lower portion of the home. A less common cause is “dynamic wind loading”. It occurs on windy days when there is more air leakage on the leeward side of the home than on the windward side.

No. A larger chimney diameter will allow for a greater volume of exhaust, but will waste heat while doing it. A smaller diameter chimney will create draft more efficiently, leaving more heat to be exchanged into the home. Each appliance has an ideal size, which appliance manufacturers have already taken into account.

An interior chimney is always more efficient and usually less expensive. An interior chimney will stay cleaner, is less likely to experience a chimney fire, starts more quickly, and is far less likely to experience down drafting. In some situations, when it is not possible to install the chimney on the interior of the home, the homeowner will need to adjust his/her expectations of the system.

An insulated metal chimney is more efficient, starts more quickly, is more durable, stays cleaner, is certified to withstand multiple chimney fires, and installs more quickly.

No. The code for Canada requires that metal chimneys serving wood burning appliances meet the CAN/ULC-S629 Standard. The standard is very difficult to meet, resulting in many manufacturers using thicker walls. 1” wall S629 chimney has been available for about 20 years.

Manual dampers can be installed when stoves are experiencing control problems caused by excessive chimney draft or excessive combustion air intake. Dampers are rarely needed on EPA stoves. Manual dampers are NOT to be used on appliances with automatic air intake controls; these appliances must only use barometric dampers.

Don’t bother, it is dangerous. It is also difficult to increase the net efficiency of your system using this technique. See below for better ideas.

Properly seasoned firewood has been cut, split, stacked in long rows, bark side up, end grain exposed, raised slightly above the ground, with breezeways between rows, the top covered to protect it from rain, in the sunniest spot possible, for a minimum of 12 months.

First, properly season your firewood to reduce its moisture content. Water in firewood needs to be heated to exhaust it up the chimney. Water absorbs a lot of heat, a lot of heat that could be heating your room. Next, consider upgrading to a better stove. A top quality EPA stove can reduce your wood consumption by as much as two thirds. After that, improve your chimney and stovepipe configuration. Eliminate or minimize any draft wasting offsets and horizontal sections. If possible move exterior chimneys indoors, penetrating the home’s vapour barrier at the highest point, and protect exterior portions of the chimney with insulated enclosures. Resize your chimney and stove pipe to match the appliance flue collar. Finally, make sure that your home has a make-up air supply. Home depressurization will increase how hard your chimney must work.

An insert is an appliance that is inserted into an existing wood fireplace, relying on that existing fireplace to contain the heat the insert produces. A fireplace is a factory built appliance or site built masonry structure designed to self-contain the heat which it produces.

Steady state efficiency measures the maximum efficiency of the fireplace after it has been running long enough to reach its peak operating temperature. The figure it gives is not the actual efficiency achieved by the fireplace unless it runs continuously year round. Steady state efficiency is not recognized for gas fireplaces in Canada.

Annual fuel utilization efficiency (AFUE) takes into consideration not only normal operating losses, but also the fact that the fireplace rarely runs long enough to reach its steady-state efficiency temperature during milder weather. This figure is useful because it is a good indication of annual heating costs when it is used like a furnace. AFUE is not recognized for gas fireplaces in Canada.

The EnerGuide FE rating is intended to be the most accurate measurement of fireplace energy efficiency and is based on typical fireplace use. The EnerGuide FE rating is the only recognized measurement of vented gas fireplace energy efficiency in Canada.

Directly comparing the EnerGuide results is misleading, since the EnerGuide tests for gas fireplaces and gas furnaces are very different. Gas fireplace efficiencies are lower than those of a condensing power vented furnaces. A fireplace with a good efficiency rating is designed to maximize efficiency, while still maintaining aesthetic appeal. The notable trend in gas fireplaces is; that as the aesthetic appeal increases the efficiency decreases. Gas furnaces are not very appealing to look at or listen to.

Due to excessive moisture output and oxygen depletion. The combustion of natural or propane gas will consumes oxygen and will result in a large volume of both water and carbon dioxide (plus other stuff). Operating a vent free appliance in an even moderately airtight home will generate a rainforest type environment with condensation running down the walls, low oxygen levels, and high carbon dioxide levels. It will create an excellent environment for the growth of mushrooms, mold, and mildew. It will create a poor environment for humans.

A natural vent unit takes its air for combustion from the home and vents through a vertical chimney to a location above the home’s roof, where the air pressure is fairly stable. A portion of the heat from the fireplace is used to generate draft in the chimney. Natural vent gas appliances run on a low chimney draft and are very sensitive to both home depressurization and outdoor pressure changes. It is not recommended that you put a natural vent unit into newly constructed homes, older tightly sealed homes, or basements.

A direct vent unit takes its combustion air from outside the house and vents its exhaust back to very near the same location. A portion of the heat from the fireplace is used to generate draft in the chimney. A direct vent appliance is a sealed unit allowing the air pressure inside the firebox to fluctuate with the outdoor air pressure. This is very effective for side wall venting where the air pressure is very inconsistent. Since it is independent of the house envelope, this type of unit is ideally suited for newly constructed homes, older tightly sealed homes, or basements.

A power vent is a system that uses an electric motor, instead of heat, to exhaust the products of combustion outdoors. Some power vent appliances will draw combustion air from the home, while others will draw combustion air from outdoors. Power vents are generally used in difficult locations where the vent must run down below the fireplace or for long horizontal venting runs. Power vented appliances can be noisy and will not run without electricity. They are not good backup heat sources.

A standing pilot is a small flame that is used to generate electricity and to ignite the fireplace when heat is called for. This electrical system is used both to operate the gas valve and as a safety system that will shut off all gas if there is no pilot flame present. The pilot light can be easily turned on and off by the homeowner. A standing pilot will function seamlessly through a power outage making the appliance an excellent backup heat source.

Electronic ignition uses household electricity to ignite a small pilot flame which is then used to ignite the fireplace burner. This electrical system is also used to operate the gas valve. There is also a flame detection system that will shut off all gas if there is no pilot flame present. Electronic ignition will not function during a power outage unless a battery backup system is installed.

Combining direct vent with electronic ignition has been shown to be problematic in colder climates. On cold days the direct vent system will continue to cycle cold outdoor air through the firebox of the fireplace. The heat exchange system of the fireplace will reverse, exchange heat from the home into the firebox, and transport it outside through the vent system. The moisture from the home air can cause condensation on the heat exchanging surfaces resulting in corrosion, pooling of water in the lower areas of the fireplace, and damage to electrical components. Some manufacturers now recognize this problem and offer a cold climate or anti-condensation kit. These kits allow the homeowner, with the flip of a switch, to convert electronic ignition fireplaces to standing pilot. A standing pilot will warm the firebox during cold weather and prevent condensation (in homes where a single fireplace is the sole source of heat, condensation problems will not occur).

A properly designed pellet stove, correctly maintained, burning quality fuel from an ecologically friendly source, is very environmentally friendly. It is the superior heating option when compared to the burning of fossil fuels such as coal, natural gas, propane, oil, or when compared to electricity generated from fossil fuels. Wood is a renewable resource, pellet appliances have very low emissions, and pellet fuel is greenhouse gas neutral.

The technology required to combust pellets at a very high efficiency and extract the maximum amount of that heat is widely available. High efficiency pellet stoves usually have a two stage combustion system, automated ash removal, and are expensive. Most pellet stoves on the market are actually mid efficiency due to a fuel to air ratio. These use up to seven times what is actually required to combust the fuel, air which is heated inside the firebox and exhausted outdoors. Manufacturers have chosen to do this in order to reduce appliance cost, control system complexity, maintenance, sensitivity to fuel quality, sensitivity to air pressure changes, and to prevent the ash from forming clinkers.

The answer to this question depends on the net efficiency of the systems being compared and the current cost of the fuel. In general a pellet appliance should save you significant money over electricity, oil, or propane appliances. Pellet appliances are normally more expensive to operate than natural gas or cord wood appliances.

Pellet stoves are less work than cord wood appliances, but much more work than other heating appliances. Pellets need to be brought to the appliance; the appliance also requires regular ash removal, heat exchanger cleaning, ash trap cleaning, vent cleaning, and fuel to air ratio adjustment.

If you have a pellet stove you will not have bark or wood chips, but you will have plenty of fine dust. If you are careful with your cleaning and ash removal, most of the dust will be fine sawdust from the pellets.

Pellet stoves require electricity and are therefore not a good backup heat source. Battery backup systems will only operate the stove for a short period of time, and are therefore not effective in areas with prolonged power outages. Pellet stoves, like computers, are also sensitive to power surges and should be protected by a similar surge protector. Only high quality generators (with consistent power supply levels) should be used to operate pellet appliances during a power outage.