Mixing valve controller Termojet One

Termojet ONE is an expansion module, not a standalone controller. It is designed exclusively to work in conjunction with Termojet LIGHT or Termojet PROFI PLUS and adds one additional mixing circuit to the system — with a three-way or four-way valve and a circulation pump. Connection via RS bus. Four temperature sensors are included.

Technical Specifications

How It Works

The ONE module connects to the main controller via the RS bus and becomes a fully functional mixing circuit within the system. All settings — weather compensation curve, weekly schedule, return temperature protection — are configured on the main controller and automatically applied to the ONE circuit. The four included sensors provide temperature measurement for the boiler flow, valve position, return line, and outdoor temperature — no additional sensors need to be purchased.

Application Scenarios

• +1 circuit to LIGHT. LIGHT manages two zones; ONE adds a third — for example, underfloor heating in the bathroom or a dedicated circuit for the garage.
• +1 circuit to PROFI PLUS. PROFI PLUS manages three zones; ONE adds a fourth — for a utility room or extension.
• Phased expansion. Install LIGHT today — add ONE tomorrow without replacing the main controller.

Advantages of Termojet ONE

• Phased expansion without replacing the main controller — a future-proof investment from day one.
• Four sensors included — nothing to purchase separately.
• RS bus connection — one cable to the main controller, configuration via its display.
• Support for 3- and 4-way valves — compatible with standard boiler room fittings.

Termojet ONE and Heat Pump

ONE allows a low-temperature underfloor heating circuit to be added to an existing heat pump system. The weather-compensated control implemented by the main controller LIGHT or PROFI PLUS ensures optimal COP for all connected circuits. Learn more on the Termojet heat pump website.

Frequently Asked Questions

Does ONE work without LIGHT or PROFI PLUS?
No. Termojet ONE is exclusively an expansion module. It requires a main controller (LIGHT or PROFI PLUS) to operate. Without a main controller, ONE does not function.

Are separate sensors required for ONE?
No. The module ships with a set of four sensors: boiler flow, valve, return line, and outdoor temperature sensor. For connection via Wi-Fi RS, the Termojet Wi-Fi RS internet module is required, connected to the main controller.