Heat exchanger tank Galmet 400 STOJ for Maxi Plus heat pumps, model 26-409100N, polyurethane insulation

Galmet 400 STOJ is a heat exchanger tank engineered for integration with Maxi Plus series heat pumps. The unit features a double-coil heat exchanger arrangement and polyurethane insulation to reduce standby heat loss. Designed as a buffer tank and hydraulic separator, it supports hot water storage and helps stabilize flow and temperature in heat pump circuits for residential and light-commercial heating systems.

Advantages

The double-coil configuration allows simultaneous connection of two heat sources or one source plus auxiliary heating, enabling flexible system layouts. Polyurethane insulation minimizes thermal losses and contributes to consistent domestic hot water and heating performance. As a buffer and hydraulic separator, the tank reduces short-cycling of the heat pump, improves system hydraulic balance and facilitates easier commissioning and maintenance of multi-circuit installations.

Suitable for

• Integration with Maxi Plus series heat pumps in single-family homes
• Residential hot water storage and regulation
• Light-commercial heating systems requiring hydraulic separation
• Systems combining heat pump and auxiliary heat source (e.g., boiler or solar thermal)

Key specifications

• Capacity: 400 litres usable volume
• Heat exchanger: double-coil internal configuration for two independent circuits
• Insulation: rigid polyurethane foam to limit standby heat losses
• Functionality: buffer tank and hydraulic separator for heat pump systems
• Application temperature range suitable for low-temperature heat pump operation

How to use

Install the tank in accordance with local plumbing and heating regulations and the Maxi Plus heat pump manufacturer instructions. Connect the heat pump circuit(s) to the appropriate coil connections and route the supply and return lines to the heating distribution and domestic hot water systems as required. Ensure correct hydraulic balancing, valves and safety devices (expansion vessel, pressure relief valve, check valves) are fitted and commissioned by a qualified technician. Regularly inspect insulation integrity and the general condition of pipe connections to maintain performance.

Usage recommendations

For optimal operation with a Maxi Plus heat pump, size piping and circulators to maintain recommended flow rates through each coil, and schedule periodic checks of pressure, temperature sensors and valves. If combining with auxiliary heat sources, configure control logic to prioritise heat pump operation while allowing auxiliary support when necessary.