This wireless room thermostat is suitable for residential and commercial heating systems where a decentralised control solution is required. It is commonly used in single-room applications or in systems with multiple zones where wired connections are impractical. The device is designed for integration with conventional heating systems and can be used with electric or hydronic heating units. It is particularly useful in retrofit situations where running new cables is not feasible.

The thermostat operates independently of the main electrical supply, using a 3V battery (2 x AA) for power. It is intended for installation in dry, indoor environments and is not suitable for outdoor or high-humidity locations. The control mechanism is based on a proportional-integral (PI) algorithm, which allows for smooth temperature regulation without the need for a time-based schedule. The device features a manual temperature adjustment via a control knob and displays both the current and setpoint temperatures.

Technical parameters

Battery power supply	3V
Weight	5 kg
Code	RDH100RF/SET
Brand	SIEMENS

The 3V battery power supply ensures operation without reliance on mains electricity, making it ideal for retrofit or temporary installations. The switching contacts support voltages from 24 to 250V AC at a maximum load of 5(2)A, allowing compatibility with a range of heating actuators and relays. The temperature range of 5 to 30°C is suitable for most indoor heating applications, and the PI control helps maintain stable room conditions without overshooting the setpoint.

Installation and connection

Installation requires mounting the thermostat on a flat, dry surface using the provided fixing points. The device does not require any wiring to the main electrical system, but the switching contacts must be connected to the heating circuit's control wiring. Ensure that the thermostat is positioned away from direct sunlight, heat sources, or draughts to avoid inaccurate readings. A common mistake during installation is incorrect orientation or proximity to heat-emitting appliances, which can affect performance. Always verify that the battery is correctly inserted and that the switching contacts are properly connected to the actuator or relay.

Compatibility and accessories

This thermostat is compatible with standard heating actuators and relays that operate within the 24–250V AC range. It is intended for use with hydronic or electric heating systems and is not designed for use with underfloor heating or complex climate control systems. No additional accessories are required for basic operation, but it is recommended to keep spare batteries on hand for maintenance. No related products are available for this model.

Technical background for designers

The thermostat uses a PI control algorithm to adjust the heating output based on the difference between the current and desired temperature. The control knob allows for manual adjustment of the setpoint, and the device continuously compares the actual temperature with the target value to determine the required output. The housing is made of durable plastic, and the internal electronics are designed for long-term operation in typical indoor conditions. The battery life depends on usage patterns and environmental factors, but no specific service interval is provided. The device is intended for integration into systems where wireless control is preferred over wired alternatives.

Service and operation

Regular checks should include verifying the battery condition and ensuring that the display is functioning correctly. If the temperature readings appear inconsistent, check the installation location for potential interference from heat sources or drafts. No scheduled maintenance is required, and there are no service intervals specified in the technical data. If the device fails to respond to input, the battery should be replaced with a new set of AA batteries. Always disconnect the switching contacts before performing any maintenance.

Frequently asked questions

Can the thermostat be used with a 24V AC relay?
Yes, the thermostat supports switching voltages from 24 to 250V AC, making it compatible with 24V AC relays.

Is it possible to integrate this thermostat into a larger control system?
No, the device operates independently and does not support integration into larger control systems or building automation platforms.

Can the temperature range be extended beyond 30°C?
No, the thermostat is designed for a fixed temperature range of 5 to 30°C and does not support user-adjustable limits beyond this range.

Does the thermostat support time-based scheduling?
No, the device uses PI control without a time-based schedule and relies on manual temperature setting via the control knob.