Frequently asked questions

Result - Type of appliance : Wood

Do I need an EPA certified or CSAB415.1-10 certified heater?

You first have to identify what your needs are. If you are looking for ambiance, a temporary heat source in a cottage or a camp, or a simple back-up heat source in case of power failure, you do not necessarily need to invest more money in order to buy an EPA or CSAB415.1-10 certified wood heater. However, if your goal is to heat on a regular basis, the extra dollars will prove to be a good investment. Furthermore, it must be noted that certified heaters release up to 90% less particles into the atmosphere, which makes wood a renewable and clean source of heat. As a result, if the style and size of the heater you are looking for is available in a certified version, it is highly recommended that you invest in this advanced combustion technology. You will help the environment and reduce your wood consumption by up to 30%.

NOTE: If you live in the United Sates, British Columbia, Ontario, Quebec, Nova Scotia, New Brunswick or Newfoundland, EPA certified wood heaters are mandatory. Exceptions apply for certain categories of products, such as decorative fireplaces. Certain municipalities may also have by-laws that require the installation of an EPA or CSAB415.1-10 wood heater, even though the province does not have an official regulation on wood heating. It must also be noted that in Canada, the CSAB415.1-10 Standard is equivalent to the EPA Standard. A wood heater that meets this Standard will generally comply with the regulation in place.

Why is the efficiency as per the EPA’s test data smaller than the publicized optimum efficiency?

EPA refers to the CSAB415.1-10 standard for the calculation of the appliance’s efficiency. The efficiency reported as per EPA’s directives consists of an average between four different burn rates, ranging from the lowest burn rate (air intake completely closed) to the highest burn rate (air intake completely open). The optimum efficiency that we publicize is the efficiency obtained according to the same test data, but for the low burn rate only. This efficiency is more realistic for a majority of users whose heating needs require that the unit be used to maximize burn times.

Does my heater qualify under the LEED program?

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System™ encourages and accelerates global adoption of sustainable green building and development practices through the creation and implementation of universally understood and accepted tools and performance criteria. LEED is a third-party certification program and an internationally accepted benchmark for the design, construction and operation of high performance green buildings. It provides building owners and operators the tools they need to have an immediate and measurable impact on their buildings’ performance.

The Canadian Green Building Council (CGBC) certifies LEED projects. The Certification is based on the total point score achieved, following an independent review and an audit of selected Credits. With four possible levels of certification (certified, silver, gold and platinum), LEED® is flexible enough to accommodate a wide range of green building strategies that best fit the constraints and goals of particular projects. The Canadian rating systems are an adaptation of the US Green Building Council's (USGBC) LEED Green Building Rating System, tailored specifically for Canadian climates, construction practices and regulations. The rating systems are adapted to the Canadian market through an inclusive process that engages stakeholders and experts representing the various sectors of the Canadian industry.

Wood or pellet stoves, fireplaces, and inserts can qualify under LEED and obtain up to one point provided that they meet the following criteria.

Why is the BTU according to EPA test data smaller than the one advertised?


You will notice a difference between the BTU output as per the EPA’s test data and what is advertised on our web site and/or product literature. The maximum BTU output we advertise is what will be obtained with a full load of seasoned cordwood inserted inside the firebox. The EPA output, on the other hand, is what has been obtained during emissions testing. The EPA test procedure requires that a special type of wood is used and positioned inside the firebox in a manner that does not represent the way the firebox volume would normally be utilized using seasoned cordwood. The EPA test load is typically much smaller. Hence, the BTU as per the EPA’s test data is reduced. The BTU output that should be considered by a normal user is the one we advertise for seasoned cordwood.


Can I install an EPA or CSAB415.1-10 certified heater on an 8-inch chimney?

EPA or CSAB415.1-10 certified heaters function best on a 6-inch chimney (interior diameter). The problem with an 8-inch chimney is that the appliance may struggle to heat-up the air volume contained inside the chimney. A hot chimney is required to create enough draft. Poor draft will inevitably lead to poor combustion, which will cause smoke roll backs, a dirty glass, lack of heat, and a large quantity of unburned fuel inside the firebox. It is therefore highly recommended installing a 6-inch liner inside the 8-inch chimney. This liner may be rigid or flexible.

Is it recommended to keep the wood furnace's blower running continuously during winter in order to maintain a more even temperature throughout the house?

Indeed, installers often recommend this practice for oil, gas or electric central heating systems. However, it is definitely not recommended for a solid fuel fired furnace.

The heat generated by the wood furnace differs from other combustibles. As the wood load burns, the temperature varies lots based on the different stages of combustion. The temperature of the combustion gases must remain above the condensation point at all times in order to avoid the formation of creosote. The fan limit control will turn the blower off before the gases’ temperature drops under the condensation point.

In the case of a high efficiency furnace, stopping the blower will also help in keeping the firebox temperatures high enough for secondary combustion to take place. This is essential if you wish to have a clean burn and maximize the appliance’s efficiency.

Where on the hot air plenum of my wood furnace can I install the fan limit control?

The cold air forced through the furnace by the blower circulates around the firebox and is deflected towards the heat exchangers in order to transfer as much heat as possible. The hot air will then be distributed throughout the house.

The temperature inside the plenum will vary a lot from one spot to the other when the blower is running. The fan limit settings are determined in our factory such that the blower turns on when the temperature is sufficient to obtain the best heating efficiency and to turn off before the combustion gases cool down to the point where they could condense.

The proper position of the fan limit control is mentioned in all our manuals. The position of the fan limit control is of prime importance to insure the proper performance of the furnace.

Can I use my wood furnace during a power failure?

A wood furnace can be used in the case of a power failure without risking damaging the unit. The conception of the wood furnace is very similar to that of a wood stove. It is tested to withstand the intense heat of a wood fire, even if the distribution blower is not functioning due to the absence of electric current. The furnace’s efficiency will however be greatly reduced. Hot air will rise by gravity into the ductwork, but it will not be pushed into the rooms in an effective manner. In most installations, hot air circulating by gravity into the ductwork will be sufficient to keep the house warm enough to live in.

Should we install a barometric damper (draft regulator) on the exhaust pipe of a wood furnace?

In the case of older, conventional furnaces, the flame can easily reach the heat exchangers. When the installation or draft adjustment is inadequate, this tends to favor creosote build-up, which can be set on fire. Therefore, we recommend the installation of a barometric damper on this type of wood furnace.

For high efficiency furnaces (Mini-Caddy, Caddy, Max Caddy), the secondary combustion ensures that creosote is usually not a problem. The configuration of the firebox is such that the flame cannot travel to the heat exchangers. We do not supply any barometric damper with the furnaces for these reasons. However, a barometric damper is recommended in the case of excessive draft. Excessive draft occurs when combustion cannot be slowed down by closing the primary air inlet.

What will happen if there is a power outage and my wood furnace is in the middle of a combustion cycle?

It is important to note that the safety standard requires the simulation of a power outage and that the clearances stated on the unit’s certification plate reflect this abnormal situation.

A wood furnace can be used temporarily without electricity, taking into account the following guidelines:
#1- Remove the access panel to the fan in order to favor a natural circulation through the hot air distribution ducts.
#2- Manually position the air control plate slightly open (max 1/16"). An opening of only 1/8" is equivalent to a high intensity fire. Frequent monitoring is recommended to ensure that the furnace temperature is under control.
#3- Do not use more than 50% of the firebox volume. It is best to use a smaller amount of wood and reload more frequently to avoid the risk of overheating.

Why does the electric unit overheat and trigger the manual reset thermodisc.

Possible causes are the following:
  1. The air filters are clogged or very dirty.
  2. The blower does not start (the first sequencer does not close or the motor is defective).
  3. The cold air return volume is not sufficient.
  4. There is excessive static pressure (the distribution duct is too small or there are not enough outlets).
  5. The heat sensor is defective (rare).
  6. The insulation between the cold air return cabinet and the air distribution cabinet is cut too short and restricts or diverts the air flow at the exit of the electric element, thus creating artificial overheat (rare).

Why can’t my Max Caddy heat my house when my old 150,000 BTU oil furnace could do it without any problem?

An oil-fired furnace will reach its maximum heat output within minutes of start-up and keep that pace as long as there is a call for heat. A wood furnace will generate its maximum heat output only at the peak of the combustion cycle. Before that, it needs to build a momentum. Then, the heat output will slowly diminish as the wood load gets consumed.

The performance of the wood furnace will also be affected by the quality of the combustible, which is not as constant and predictable as heating oil. It will vary a lot depending on the density and moisture content. Numerous other factors may also affect the performance of the furnace, such as a poor chimney draft, dirty heat exchangers, low static pressure, etc.

Can the Caddy add-on be installed with an existing propane or natural gas furnace?

The certification allows the installation with the two types of gas. Therefore, the Caddy add-on may be hooked-up with either a propane or natural gas furnace, provided that the gas unit’s output power does not exceed 35.17 kW (120,000 BTU/h).

Is it possible to reduce the fan speed of my PSG furnace to reduce the noise level?

Except for the Max Caddy and the Caddy Alterna, the blower motor on your furnace has four speeds and the installer will have to select two, that is one speed for continuous air circulation during the summer months (low) and one speed for heating. The latter will be selected in accordance with the ducts design and the air distribution needs (normally med-low or med-high).

Electrically speaking, the circulation and heating speeds may be the same if you connect both the black and red wires on the same terminal. You should however take note that reducing the heating speed will reduce the heat exchange and the furnace’s temperature will increase accordingly, which could cause the furnace to overheat.

Should you choose to reduce the blower speed, be certain that the primary air intake damper closes completely when the thermostat is not calling for heat so that in the case of an overheat, the damper motor being deactivated, the furnace will go into slow combustion and the blower will be capable of cooling it down.

Less air flow through the electric unit of a wood/electric combination furnace could also increase the risk that the overheat protection on the unit will trip. This is especially true if the air filter is dirty. This situation will leave you with no electric heat until the sensor is manually reset.

How do I determine what furnace I need between the Mini-Caddy, Caddy and Max Caddy?

We have a “rule of thumb” that is not scientific, but that can give you a good idea on what PSG product you need to install in your house.

We assume that the house has an average insulation, quality windows and doors and 8 foot ceilings, with a location in an area where winter temperatures are comparable to most Canadian areas. We do not count the basement. Start by calculating the area of the main floor and add 50% of the area of a second floor when applicable. If you do not exceed 1,000 square feet, the Mini-Caddy is adequate. Up to 1,700 square feet, a Caddy installed and operated as recommended should satisfy your heating needs. Above 1,700 square feet and up to 3,000 sq. feet, the Max Caddy should be used.

Of course, nothing can replace a heat loss calculation conducted by a forced air heating professional to determine your exact heating needs and verify your existing ducting for compatibility.

How do I reduce the amount of charcoal my heater produces?

Appliances that are EPA or CSAB415.1 certified tend to create larger coal beds due to their higher efficiency. This can be controlled by the way you burn your appliance. After an overnight burn, you may have a more significant coal bed. Simply rake the coal bed forward and add a smaller piece of wood on top. Burn the appliance on a higher setting (air control fully open). This will pull more primary air into the firebox and will increase draft. The coal bed will burn down with the log. You may have to repeat this operation a couple of times before the coals are reduced. You are then ready to load your appliance with a larger fuel load.

Can I add an air conditioning unit to my PSG wood-heating system?

It is possible to use the furnace blower and duct system to install an air conditioning coil. A good control technician can easily connect it without interfering with the safe operation of the furnace. It is prohibited to install the air conditioning coil in the cold air return. The condensation produced will make the firebox rust.
In the case of a wood furnace, we recommend installing the AC coil downstream of the furnace, in a by-pass duct equipped with a damper that can be closed during winter to protect the AC coil from direct radiation of the furnace. In the case of a power failure, the distribution blower would cease working, which could cause excessive temperatures in the plenum that could cause the plastic pan of the AC coil to melt. In the case of a pellet furnace, the AC coil can go directly into the hot air plenum, provided that the plastic pan of the AC coil resists to at least 400 °F. A power outage would cause the pellet feed to stop, which would prevent an overheating of the hot air plenum.

My furnace is a wood electric combo. Is it possible to burn wood and run the fan with a generator in case of a power failure?

First, please note that your PSG furnace, if installed in accordance with the clearances, may be operated without the blower during a power outage, if authorized and mentioned in the manual. In such a case, it is recommended to open the blower access panel to help circulate hot air in the ducts by gravity. You also need to heat moderately. Note that the air intake damper motor will not work without power. It will need to be operated manually. It is possible to feed the blower with a generator, but you must make sure that the power from the house’s electrical panel is cut off to prevent conflict when the power is restored. This can be done automatically with the use of a suitable relay.