DETTSON Suprême Avantage SUP30-A120D20 Electric Furnace | 30 kW - 240V
The 3-wire 30 kW Dettson Suprême Avantage: the largest size in the series that we offer, with a 4-speed PSC motor and a 120–240/208 V supply on two circuits.
Model numberSUP30-A120D20
514 316-2973 · sales@airgreen.ca
Quick facts
30 kW of central electric heating, on a 3-wire supply
When to choose the 30 kW size
The Dettson Suprême Avantage SUP30-A120D20 is the largest size in the Suprême series that we offer: 30 kW at 240 V. It is meant for homes with high heating needs, for example a large house with a finished basement or rooms that are hard to heat. This is not a choice made by eye: we base it on an assessment of the house, done during the free in-home estimate, and we recommend the size that matches the actual needs rather than the largest one by default.
Voltage matters too. In a building supplied at 208 V, the furnace delivers 22.5 kW, or 76,884 BTU/h, instead of 30 kW. It connects at 120–240/208 V single-phase, 3-wire.
Two electrical circuits to plan for
At 30 kW, Dettson splits the supply over two terminal blocks. Block 1 needs a breaker of no more than 70 A and block 2, no more than 100 A, at 240 V (60 A and 90 A at 208 V). The published total current reaches 135.7 A at 240 V. Whether the house is in Montreal, Laval or on the South Shore, we always check the electrical service and the room in the panel before confirming this model. Copper and aluminum wire are both approved.
Day to day and at maintenance time
The blower is driven directly by a 1 HP four-speed PSC motor, set at installation to suit the ductwork. On the front of the painted steel cabinet you find the breakers, a continuous fan switch, a low/high power switch and a heat-demand indicator light. The elements switch on in sequence and can be replaced individually, and there is a single 20 x 20 in filter to keep an eye on.
The furnace takes an air conditioner or heat pump coil of up to 5 tons, on the supply or return side. With a heat pump, Dettson prohibits running the elements and the heat pump at the same time, as this would cause overheating; the system must be non-simultaneous, and the K03081 interface kit is offered by the manufacturer.
Installation by AirGreen
AirGreen is a family business established in Montreal for more than fifteen years, holding RBQ licence 5645-9605-01 for ventilation, refrigeration and electrical work. After the estimate, we install the furnace in the position that suits the space: upflow, downflow (on the DFB-SUP base if the floor is combustible), horizontal or suspended. It is 36 1/2 in high and 22 in deep, weighs 105 lb and is approved for zero clearance. We connect the plenum to the 20 x 20 in supply opening, wire the two circuits, set the motor speed and check the temperature rise, published at 55 to 75 °F at 240 V. Our teams also cover Longueuil and the North Shore.
Your quote
Ask for your free in-home estimate for the Suprême Avantage SUP30-A120D20. We give you a written quote, and financing is available.
When a home calls for the largest size
The SUP30-A120D20 delivers 30 kW at 240 V, the largest Suprême size that we offer. It connects at 120–240/208 V, 3-wire, and its 1 HP four-speed PSC motor distributes the heated air through the ductwork.
- Homes whose heating-needs assessment confirms a 30 kW size
- Replacing an electric furnace where the supply is 3-wire
- Buildings supplied at 208 V, where the furnace delivers 22.5 kW
- Adding a central air conditioner or heat pump with a coil of up to 5 tons
Specifications
From the manufacturer’s documentation. A value the manufacturer does not publish is not listed.
What to know before installing
- 120–240/208 V single-phase, 60 Hz, 3-wire power supply.
- Two supply circuits: terminal block 1, breaker of no more than 70 A at 240 V (60 A at 208 V); terminal block 2, breaker of no more than 100 A at 240 V (90 A at 208 V).
- Ampacity calculated per CSA C22.2-236: 64.8 A and 98.4 A at 240 V; 56.4 A and 85.2 A at 208 V. Total current of 135.7 A at 240 V.
- With a heat pump, Dettson prohibits running the elements and the heat pump at the same time (risk of overheating): a non-simultaneous system is mandatory, with the K03081 interface kit offered by the manufacturer.
- For downflow on a combustible floor, the furnace sits on the DFB-SUP base.
- The furnace alone is not a heat pump: it does not qualify for the LogisVert grant.
Manufacturer documents
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Frequently asked questions
How do I know whether 30 kW is the right size?
Through an assessment of the home’s heating needs, done during our free in-home estimate. We recommend the size that matches the actual needs, not the largest one by default.
What happens if the building is supplied at 208 V?
The furnace then delivers 22.5 kW, or 76,884 BTU/h, instead of 30 kW at 240 V. We check the supply voltage during the estimate.
Which breakers are needed?
Two: no more than 70 A for block 1 and 100 A for block 2 at 240 V, or 60 A and 90 A at 208 V. We check that the electrical service and the panel can take them.
Can a heat pump be added later?
Yes, with a coil on the supply or return side, up to 5 tons. Dettson prohibits running the elements and the heat pump at the same time, as this would cause overheating; the system must be non-simultaneous, with the K03081 interface kit.
What does the manufacturer’s warranty cover?
According to Dettson: 5 years on parts for residential use, 1 year for commercial use. Labour is not covered by the manufacturer.
A 3-wire 30 kW Suprême Avantage, 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.