THERMO 2000 BuffMax BUFF20-1.25NPT-HRZ-HC Buffer Tank (20 gallons)

A small buffer tank that gives your electric boiler room to breathe

The Thermo 2000 BuffMax BUFF20-1.25NPT-HRZ-HC buffer tank is the smallest size in the BuffMax series: an insulated 20 US gallon vessel installed between the heat source and the zones of a hot-water heating system. Thermo 2000 designs it as a 3-in-1 unit: it works as a buffer tank, a storage tank and a hydraulic separator at the same time.

Who the 20-gallon size is designed for

A modern electric boiler holds little water. When a single small zone calls for heat, such as a bathroom with a radiant floor, the boiler reaches its temperature quickly, shuts off, then starts again a few minutes later. Air-to-water heat pumps also benefit from running longer cycles. The BUFF20 adds a reserve of hot water to the loop: the source runs longer each time it starts and the zones draw from the tank. Thermo 2000 recommends the BuffMax for low-mass boilers, heat pump systems and multi-zone systems.

This size suits small systems best: a basement heated by a radiant floor, a condo or small plex heated with water, an attached garage, or a house with many small zones. The HC code means it also accepts chilled water, so the same tank stays in place if your air-to-water heat pump feeds fan coils for cooling in summer.

A tank that fits in a small mechanical room

At 54 inches high and 16 inches in diameter, the BUFF20 fits next to a wall-hung boiler, in a basement utility room or in a mechanical closet with enough clearance. Its adjustable legs make up for a concrete floor that is not perfectly level, which is common in older homes in Montreal and Longueuil. Its four 1 1/4 in NPT side connections, two on each side, separate the boiler circuit from the zone circuit: each circulator works on its own side without disturbing the other.

The 2-inch HFC-free polyurethane insulation limits heat loss to 1/2 °F per hour, according to the manufacturer. The stored water stays available for the zones instead of heating the mechanical room. The tank accepts a maximum working pressure of 150 psi and a maximum temperature of 121 °C (250 °F). It must never be connected to domestic hot water or to a system open to the atmosphere: it works in a closed loop only.

What AirGreen’s installation covers

We install the BuffMax on hot-water heating systems supplied by an electric boiler or an air-to-water heat pump, in Laval, on the North Shore, on the South Shore and throughout Greater Montreal. Our work includes:

• the free on-site visit and estimate, with the size chosen according to the heat source and the number of zones;
• connecting the four hydraulic separation connections, the automatic air vent, the drain valve and the supplied temperature and pressure indicator;
• placing your boiler’s or heat pump’s sensor in the immersion well, when its control uses one;
• filling, purging and commissioning the loop.

AirGreen is a family business established in Montreal for more than 15 years, holding RBQ licence 5645-9605-01 (ventilation, refrigeration and electrical). You receive a written quote before work begins. Thermo 2000 warrants the tank for 5 years and the mechanical parts for 2 years, under its terms.

Let’s move on to your project

Send us the brand of your boiler or heat pump and the number of zones: we check whether the BUFF20 is enough or whether a larger size is needed. Ask for your free estimate and learn about the financing available.