Rehau STAR 20 User manual

Analogue Electronic Room Temperature controller for
underfloor heating.
Operating and mounting instructions
General
Congratulations on choosing the new REHAU room controller. In
selecting the REHAU Star 20 you have chosen an analogue electronic
room temperature controller which oers key advantages over conven-
tional mechanical products. This unique controller is easy to operate
using the conventional backlit adjusting dial. The illuminated dial gives
the extra function of displaying when room set point is achieved. It
also oers you unique control simplicity for heating applications of all
types thanks to the high quality device electronics. This electronic
control system ensures that the set room temperature is maintained
and when required a time signal input automatically activates a
reduction in temperature (night setback).
Building regulations and the environment
REHAU have a commitment to assist building owners and occupiers
to reduce their carbon footprint, by reducing the energy used for
heating systems and hot water. One eective method is to burn fuel
when there is a demand for heat from the boiler, either for heating or
hot water. When this demand is satisfied, the boiler should switch o
again – it should not be able to fire until a new demand is created by
REHAU STAR CONTROLS
STAR 20 -ANALOGUE ELECTRONIC ROOM CONTROLLER, ART NO: 206029
the controls. This is called Boiler Interlock and represents the mini-
mum standard required under the Building Regulations for new and
existing heating systems.
The following characteristics of the REHAU Star 20 guarantees you
precise, comfortable and energy saving operation of you room heating
system.
Technical characteristics
Pulse-Width-Modulation (PWM)
Underfloor heating has the basic problem of Temperature overshoot.
i.e. the room continues to be heated even when the valve is closed
and the desired room temperature has been reached. The REHAU Star
20 solves this problem electronically and extremely eectively using
Pulse-Width-Modulation (PWM), It operates using a constant com-
parison of desired and actual temperature. The opening period of the
actuators is adjusted as to avoid over and under shoot, therefore
the actual is much closer using PWM to the desired setpoint tem-
perature. This achieves a more precise and comfortable control of the
desired set point desired temperature.
Please note:- if the REHAU Star 20 is used for radiators or
convection heating systems, the Pulse-Width-Modulation (PWM) can
be switched o (see basic settings section).
Valve protection feature
In order to ensure that the valves remain fully functional even after
long periods of no operation - i.e. in summer, the REHAU
controller is supplied with a switchable valve exercising operation.
This ensures that the valves remain functional by operating the
output each week. This valve protection feature can be deactivated if
required.
Temperature reduction (Night setback)
It is important to reduce energy and today we have the ability to
reduce the room temperature in times of inactive or no occupancy.
Industry research has shown that this can significantly reduce the
energy required in a normal dwelling by up to 30%.
The REHAU Star 20 allows you to automatically reduce the room tem-
perature by 4K, without the need to adjust the room unit, based on a
Building Solutions
Automotive
Industry

timed input, when connected as part of a complete system.
Installation
The REHAU room unit is designed as an electronic temperature con-
troller of warm water heating systems and serves to control electro-
thermal actuators or other electrical devices.
The maximum switching current indicated in the technical data
must be observed! REHAU cannot accept any liability for any form of
misuse.
The electrical installation must be carried out in accordance to the
current wiring regulations in force and must be in accordance with the
connection plan. Only approved certified professionals may carry out
the installation. Further more the installation is always to be carried
out with the power supply disconnected.
Position the room unit such that it is not covered by curtains, pieces of
furniture or other objects. The control should not be installed close
to heat sources (i.e. lamps, fireplaces/chimneys, direct sunlight etc.)
and positioned away from draughts. Ensure that it is fitted on a flat,
solid surface that is non-conductive between 1.2-1.5m o the ground
floor. This allows the room temperature to be measured at the correct
height and results in more comfortable control.
Wall mounting
Before mounting the wall unit, take-o the housing cover from the
base plate.
1. Remove the screw on the underside
2. Open the housing by lifting the housing cover on the bottom edge
and then lifting it.
Now firmly mount the base plate on the wall or the flush-mounted
socket with the screws provided.
Connection
Wire the room unit in accordance with the following connection plan:
REHAU Star 20 230 V version
Terminals
Temperature Setback
N Neutral
L 230 V AC supply
Switching output (actuator, strip terminal)
Jumper settings
Dierent REHAU Star 20 features can be switched ON or OFF using
the jumpers shown:
REHAU Star 20 switching bridges
Switch Feature ON OFF
VP Valve protection
feature
PWM Pulse-Width-Mod-
ulation
Temperature reduc-
tion
The unit comes factory supplied with all jumpers set to ON.
You can change the settings in accordance with your requirements,
by moving the jumpers onto contact pins as above, ensure that
jumpers are fitted i.e. in the correct notation, and not removed.
Replace the cover in the reverse order to above.
Operation
The electronic REHAU Star 20 room unit, controls the temperature in
dry closed rooms with normal environment and a maximum relative
room humidity of 95% (non-condensing).
The desired room temperature can be set very easily with the control
dial. The REHAU Star 20 ensures stable room control by maintaining
the set point room temperature.
When there is a REHAU Star 50 controller connected to the room
unit it can automatically activate night setback temperature reduction
where necessary.
Cleaning
Never use anything other than a soft, dry cloth to clean the unit. Never
use any cleaning agents containing solvents or any sharp objects to
clean the unit!
Technical Data 230V
Article No: 206029
Operating Voltage: 230VAC / 50Hz
Max. switching current: 10 (3) A
Hysteresis: 0.5K
Protection Rating: IP 30
Dimensions W/H/D: 80mm/80mm/30.5mm
Temperature range: 5°C - 30°C
Storage temperature: -25°C - 65°C
CE Approved
UK & IRELAND SALES OFFICES
London, REHAU Ltd, The Building Centre, 25 Store Street, London WC1E 7BT Slough, Units 5 J & K, Langley Business Centre, Station Road, Langley, Slough SL3 8DS Phone:
01753 588500 Fax: [phone] Glasgow, Phoenix House, Phoenix Crescent, Strathclyde Business Park, Bellshill, North Lanarkshire ML4 3NJ Phone: [phone] Fax:
01698 503701 Dublin, 9 St. Johns Court, Business Park, Swords Road, Santry, Dublin 9 Phone: 00353 (0)1 8165020 Fax: 00353 (0)1 8165021