THERMO 2000 AltSource 50 Thermal Mass Electric Boiler | 7.5 kW - 240V
The 7.5 kW AltSource 50 is a 48 US gal thermal mass electric boiler whose output comes on in two stages, as the backup of a renewable heating system.
Model numberALTSOURCE50-7,5
514 316-2973 · sales@airgreen.ca
Quick facts
Two stages, 7.5 kW and 48 US gal of water: a graduated electric backup for geothermal and air-to-water heat pumps
A backup designed for renewable systems
A geothermal system or an air-to-water heat pump can carry most of a home’s heating. It still needs a backup, and that is the role Thermo 2000 gives the AltSource: a thermal mass electric boiler that serves as the backup source of a renewable-energy heating system. The manufacturer presents it as the only high water volume electric boiler on the market.
The AltSource 50-7.5 combines a 48 US gal tank with 7.5 kW of output at 240 V, or 25,590 BTU/h according to Thermo 2000. The output is split between two elements, one of 3 kW and one of 4.5 kW, which come on in two stages. It is a mid-range size, designed for a mid-size house whose main source does most of the work.
The controller does the fine work
The T2 UltraSmart controller and its outdoor sensor are supplied. They set output and water temperature according to the outdoor temperature, shut heating off in warm weather and offer a Boost mode. The controller runs in standalone electric mode, the default setting, or in automatic transfer controlled by an external contact: we choose the mode based on how your main source is connected.
How it fits a home in Laval or on the North Shore
Take a split-level house in Laval or on the North Shore, heated by a radiant floor on two levels and an air-to-water heat pump. The AltSource 50-7.5 goes in the mechanical room: 22 in in diameter, 25 1/2 in deep with the door, 56 7/16 in high and 280 lb before filling. It connects to the loop through 1 in male NPT fittings and operates at a maximum pressure of 30 psi.
The electrical circuit calls for a 40 A breaker and Cu 8 / Al 6 wire gauge at 240 V, according to Thermo 2000. In a building with a 208 V supply, output becomes 5.6 kW (27.2 A). For the expansion tank, the manufacturer recommends a #30 with baseboards or a radiant floor, and a #60 with cast-iron radiators.
Our installation, step by step
- Free on-site estimate: main source, hot-water loop, electrical panel and space.
- Written quote that specifies the unit, circulator, expansion tank and electrical work.
- Setting the unit in place, connecting it to the loop and mounting the outdoor sensor and supplied accessories.
- Electrical connection, filling, purging and controller setup, then a check with you.
AirGreen is a family business established in Montreal for more than fifteen years, holding RBQ licence 5645-9605-01 in ventilation, refrigeration and electrical work. Thermo 2000 covers the tank for 15 years in residential use and the electrical and mechanical components for 2 years.
Take the next step
From Montreal to Longueuil, from Laval to the North Shore and the South Shore, ask for your free estimate. You receive a clear written quote, and financing is available.
An electric backup that steps up in stages
With one 3 kW and one 4.5 kW element, the AltSource 50-7.5 brings its output on in two stages. The T2 UltraSmart controller adjusts output to the outdoor temperature, as the backup of a geothermal system, an air-to-water heat pump or solar collectors.
- Backup for a geothermal system in a mid-size house
- Backup for an air-to-water heat pump feeding hot-water baseboards
- Split-level house with radiant floor heating on two levels
- Replacing an electric boiler with a thermal mass unit
Specifications
From the manufacturer’s documentation. A value the manufacturer does not publish is not listed.
What to know before installing
- 240 V single-phase circuit: Thermo 2000 lists a 40 A breaker and Cu 8 / Al 6 wire gauge.
- At 208 V, output drops to 5.6 kW (27.2 A), according to the manufacturer.
- The circulator and expansion tank are not among the supplied parts. Recommended tank: #30 for baseboards or a radiant floor, #60 for cast-iron radiators.
- Height of 56 7/16 in and weight of 280 lb, plus the water in the tank once filled.
- Maximum working pressure of 30 psi (207 kPa); 1 in male NPT fittings for supply and return.
- 30 psi (207 kPa) relief valve
- Drain valve
- Temperature and pressure gauge
- Automatic air vent
- Heating elements
- UltraSmart controller
- Outdoor sensor
Manufacturer documents
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Frequently asked questions
How do the two elements work?
Thermo 2000 splits the 7.5 kW between a 3 kW element and a 4.5 kW element, in two stages. The T2 UltraSmart controller modulates output on the outdoor temperature, measured by the supplied sensor.
What electrical circuit is needed?
A 240 V single-phase circuit with a 40 A breaker and Cu 8 or Al 6 wire gauge, according to the manufacturer. We check the room left in your panel during the estimate.
What if the building has a 208 V supply?
The AltSource also runs at 208 V, but its output becomes 5.6 kW and its current 27.2 A. We take this into account when choosing the right size.
Which standards does the unit meet?
Thermo 2000’s specification sheet lists CSA C22.2 No. 165-92 in Canada and UL 834 in the United States.
Can you install it?
Yes. We set the boiler in place, connect it to the loop and the electrical circuit, mount the outdoor sensor, then fill, purge and set up the system.
A 7.5 kW AltSource 50, 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.