THERMO 2000 Mini BTH 4.5 Electric Boiler | 4.5 kW - 240V

A 4.5 kW wall-mounted electric backup for your heat pump or geothermal system

When the main source needs support

A heat pump, a geothermal system or solar collectors heating a water loop do most of the work, but there are times when they are no longer enough. You then need a simple, reliable electric source that takes over on the same loop. Thermo 2000 designed the Mini BTH for that role, and the 4.5 kW size suits homes where the backup load stays modest.

The Mini BTH 4.5 heats water with a single 4.5 kW element, or 15,354 BTU/h at 240 V. Its body holds only 1 US gal of water and mounts on the wall, in several positions. On its own, it also suits a condo heated by hydronic baseboards or the radiant floor of a finished basement. Thermo 2000 points out that it runs quietly and with no GHG emissions.

A boiler that is simple to integrate

On the electrical side, the manufacturer specifies a 240 V circuit with a 30 A breaker and Cu 10 or Al 10 wire. In buildings supplied at 208 V, common in Montreal, it gives 3.4 kW (16.3 A): we check the voltage before settling on the size.

On the water side, it accepts 3.0 US gpm at a 10 °F temperature difference, or 1.5 US gpm at 20 °F, with negligible pressure drop according to Thermo 2000. Its four 3/4 in female NPT connections, for inlet and outlet, simplify the tie-in to the existing loop, a point Thermo 2000 highlights for wall mounting. Water can be set from 50 °F to 190 °F (10 °C to 90 °C), at a maximum working pressure of 30 psi.

Control is by aquastat, with an element indicator light, a switch and a 24 V supply for the thermostat and accessories. The Mini BTH has no outdoor sensor. For safety, an automatic high limit cuts out at 208 °F (98 °C) and a manual limit at 227 °F (108 °C).

What our installation includes

It all starts with a free on-site estimate, where we look at the main source, the water loop, the electrical panel and the wall that will hold the boiler. You then receive a written quote that specifies the circulator and the expansion tank to add, since Thermo 2000 does not supply them.

Our technicians mount the boiler, connect it to the loop, install the supplied 30 psi relief valve and temperature and pressure gauge, make the electrical and control connections, then fill, purge and test the backup 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 warrants the tank for 15 years and the electrical and mechanical components for 2 years.

Add backup to your system

We install the Mini BTH in Montreal, Laval, Longueuil, on the North Shore and on the South Shore. The estimate is free, the quote is in writing and financing is available.