STELPRO SFECM SFECM2021 Electric Furnace | 20 kW - 240V
The Stelpro SFECM2021 electric furnace: 20 kW at 240 V, a 1/2 HP variable-speed ECM motor and airflow set separately for each heating stage and for cooling.
Model numberSFECM2021
514 316-2973 · sales@airgreen.ca
Quick facts
20 kW, an ECM motor and two clearly distinct heating stages
Heating in two steps
The Stelpro SFECM2021 produces 20 kW at 240 V. Its electronic board modulates individually framed elements, and its 1/2 HP variable-speed ECM motor adapts the airflow to what the thermostat calls for. In mild weather, the first stage (W1) is often enough, with airflow set within a lower range. When the cold deepens, the second stage (W2) takes over with higher airflow. 7-position potentiometers set each of these ranges, as well as those for cooling (Y1) and continuous fan.
Stelpro highlights the constant airflow and better efficiency of its ECM motor, and adds Y2, air cleaner and humidifier terminals on the SFECM.
1/2 HP or 1 HP version
At 20 kW, Stelpro offers two ECM motors. The SFECM2021 uses the 1/2 HP, while the SFECM20211HP moves up to 1 HP for duct systems that need more air. If your ducts and cooling equipment are well served by the published range, up to 1,450 CFM, the 1/2 HP version does the job. We check the ductwork before recommending one or the other.
Example: an open-concept home
In Longueuil, an open-concept home heated through ducts can see temperature differences between the kitchen, the living room and the upper floor. A low-speed continuous fan, published at 300 to 700 CFM, helps reduce them. The SFECM2021 goes in the basement upflow, against a wall with zero clearance, horizontal, or downflow with the FSB2 adapter, sold separately.
If a central heat pump is added, Stelpro provides Type A (factory setting: heat pump downstream, elements off during its call) or Type B (heat pump on the return side: furnace backup in cold weather), with compensation during defrost.
Our installation
Stelpro publishes a total amperage of 85 A at 240 V and 74 A at 208 V, a voltage at which the output becomes 15 kW. AirGreen, a family business established in Montreal for more than fifteen years and holder of RBQ licence 5645-9605-01 for ventilation, refrigeration and electrical work, checks these points during the free estimate, then gives you a written quote.
On the day, our technicians replace the old unit, connect the furnace to the ducts, make the electrical connection according to the manual and the rating plate, set each airflow range and configure the thermostat. Plan for the 20 x 20 x 1 in filter: it is not supplied.
Ask for your estimate
In Montreal, Laval, Longueuil, on the North Shore and the South Shore, we come to you for a free estimate and give you a written quote. Ask us about financing options too.
20 kW with airflow that follows the heating stage
The SFECM2021 modulates its elements with an electronic board and leaves air moving to a 1/2 HP ECM motor. Airflow for first-stage heating (W1), second stage (W2), cooling (Y1) and continuous fan is set separately.
- Large homes whose heat loss calculation comes to 20 kW
- Two-stage thermostats, with lower airflow on the first stage
- Homes planning a two-stage central heat pump (Y2 terminal)
- Adding a humidifier or an air cleaner connected to the board
Specifications
From the manufacturer’s documentation. A value the manufacturer does not publish is not listed.
What to know before installing
- Sold alone, an electric furnace is not a heat pump: it does not qualify for the LogisVert grant.
- Total amperage of 85 A at 240 V and 74 A at 208 V. Breaker and conductor sizes are confirmed from the installation manual and the rating plate.
- At 208 V, the published output is 15 kW.
- For higher airflow, Stelpro offers the same output with a 1 HP ECM motor (SFECM20211HP).
- Not included: 20 x 20 x 1 in filter, FSB2 adapter (downflow) and SCOND neutral terminal block.
- Filter frame for a standard 20 x 20 x 1 in air filter (filter not included)
Manufacturer documents
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Frequently asked questions
What do W1 and W2 mean?
They are the thermostat’s two heating stages. On the SFECM2021, the first stage (W1) is set within a lower airflow range than the second (W2), according to the values Stelpro publishes. We set both during commissioning.
SFECM2021 or SFECM20211HP?
Both deliver 20 kW. The SFECM20211HP has a 1 HP ECM motor. The SFECM2021 keeps the 1/2 HP motor, with cooling published up to 1,450 CFM. The choice depends on the airflow your ducts and the matched equipment require.
Can it be paired with a heat pump?
Yes. In Type A (factory setting), the heat pump is downstream and the elements do not heat during its call. In Type B, it is on the return side and the furnace makes up for its loss of capacity in cold weather. The Y2 terminal accepts two-stage cooling.
What amperage should be planned for?
Stelpro publishes a total amperage of 85 A at 240 V and 74 A at 208 V. We check your electrical service during the estimate, then the breaker and conductors from the manual and the rating plate.
What warranty does Stelpro offer?
Stelpro warrants the furnace for 5 years from the date of purchase against defects in material or workmanship, for the original purchaser only. Disconnection, transport and installation are not covered by the manufacturer.
A 20 kW Stelpro SFECM furnace, installed by AirGreen
Tell us about your project: we check the sizing, confirm availability and send you a quote. Or let our technicians install it for you.
Specifications from the manufacturer’s documentation, checked on October 19, 2026.