Room Controllers

The Heat6 contains six room temperature controllers. Each one is configured on its own, can be given a name of up to 30 characters, and drives either a valve output on the same device or an actuator elsewhere on the bus.

Temperature reference

A controller reads its room temperature from one external sensor, or from two external sensors combined with a weighting from 10:90 to 90:10. If one of the two fails, the controller uses the other. The device sends a read request to the sensors after a download and after voltage recovery, and can poll them cyclically.

If the temperature is unavailable, the controller falls back to a configured control value, set separately for summer and winter when summer/winter mode is enabled.

Heating and cooling

A controller runs in heating mode, cooling mode, or both. In combined mode you choose how it changes over, either from a bus object or automatically once the temperature passes the setpoint by an upper or lower dead zone of 0.5-10 K. The controller supports 2-pipe systems, where one valve carries both hot and cold water, and 4-pipe systems, where heating and cooling have separate valves.

With summer/winter mode enabled, the changeover can be limited so that only cooling runs in summer and only heating in winter.

Control types

• 2-point: switches on and off around the setpoint, with a separate upper and lower hysteresis of 0-20 K. A small hysteresis holds the temperature tighter but sends more telegrams.
• PWM with PI control: sends on and off telegrams whose duty cycle follows the PI control value, over a cycle of 1-255 minutes.
• Continuous with PI control: sends the control value as a percentage, on change and cyclically.

The PI response comes from a preset: hot water heating, underfloor heating, electrical heating, cooling ceilings, split units or fan coil units. You can also set it by hand, with a proportional range of 1-10 K and a reset time of 0-255 minutes.

Operation modes and setpoints

Each controller supports comfort, standby, economy and frost/heat protection, switched by 1-bit or 1-byte objects. Comfort can also be extended for a set time, after which the controller returns to the previous mode.

Setpoints are defined in one of two ways:

• Relative: a base setpoint for comfort, with standby and economy derived from it by a fixed offset for heating and cooling.
• Absolute: an independent setpoint for every mode.

The setpoint can also be shifted by an additional offset in steps of 0.5 K or 1 K, within limits you set. Every setpoint stays inside the configured minimum and maximum of 5-37 °C. The frost and heat protection setpoints are set in ETS only and are not limited by that range.

Window contacts and presence

A window contact switches the controller to economy or to frost/heat protection after a delay, and returns it to the previous mode when the window is closed. A presence signal from the bus switches the controller to comfort and releases it again when presence ends. Telegrams that arrive in the meantime are recorded and applied afterwards.

Scenes

Each controller has five scenes, each assigned a scene number from 1 to 64. A scene sets the operation mode, or the setpoint temperature when operation modes are disabled. Scenes are recalled and stored from the bus, and a stored scene survives a bus voltage failure.