2
CM900 Wireless - Programmable Room Thermostat
1) Installation Information
As these products communicate using RF technology special care must be taken during installation. The
location of the RF components as well as the building structure may influence performance of the RF
system. To assure system reliability, please review and apply the information given below.
Within a typical residential building the two products should communicate reliably within a 30m range. It
is important to take into consideration that walls and ceilings will reduce the RF signal. The strength of
the RF signal reaching the Relay Box depends on the number of walls and ceilings separating it from the
room thermostat, as well as the building construction - the diagram below illustrates an example of typical
signal strength reduction. Walls and ceilings reinforced with steel or plasterboard walls lined with metal foil
reduce the RF signal significantly more.
Once a position is selected for the room thermostat this can be checked using the RF Communication Test
mode as described in section
2.2.3 Locating the Room Thermostat
. If the position is unsuitable the Relay
Box will not respond and an alternative position must be selected.
Typical example of Building Fabric Signal losses
Wall
Wall
Wall
Ceiling
Max. Signal Length 30 metres
= Signal Strength
