Functional description

Room temperature controller and VAV terminal unit, including control components, form a functional unit that allows occupants to control the room temperature individually and at the lowest possible energy consumption. It also allows to control the water valves of hot water or chilled water systems.
The room temperature control is a closed loop control. The controller is fitted with a temperature sensor that measures the room temperature. The setpoint value can be a constant value or it can be changed by room occupants.
The controller compares the actual value with the setpoint value and alters the volume flow rate setpoint value and/or the valve settings accordingly.
The room temperature control is P control or PI control.
Maximum energy efficiency is achieved because of demand-based operating modes that can be activated by the room occupant or at a higher level.

Operating modes
Energy-saving mode
The room temperature is so that devices will not suffer, i.e. the setpoint temperature for heating is very low, and the setpoint temperature for cooling is very high, i.e. in a room with an open window.

Stand-by mode
The setpoint temperature for heating is slightly reduced, and the setpoint temperature for cooling is slightly increased, e.g. for a room that is currently not used.

Frost
If the room temperature falls below 10 °C, the anti-freeze function is activated.

Changeover
Changeover from cooling to heating or from heating to cooling.

Boost
The room can be ventilated, heated, or cooled with maximum volume flow (q_vmax) at maximum output.

Application

• Room temperature controller CR24-B1 with one output, for single room applications
• Cooling or heating mode (changeover)
• Analogue output 0 – 10 V DC for the control of VAV terminal units with Easy, Compact or Universal controllers

Parts and characteristics

• Attractive unit for wall mounting, signal white (RAL 9003)
• Integrated temperature sensor
• Setpoint value adjuster
• Operating mode push button
• Status indicator light
• Analogue output 0 – 10 V DC for variable volume flow control
• Analogue inputs 0 – 10 V DC for external temperature sensor and for external setpoint changes
• Digital inputs for energy-saving mode, standby operation or changeover
• Micro switch for configuration
• Communication port for adjustment devices

Commissioning

• Configure the control function using a micro switch
• Functional test