INSTALLATION
Please read the important safety information at the start of this manual before you start to install the device.
The ideal position to locate the ST620 thermostat is about 1.5m above floor level. It should be mounted in a
location where the thermostat is accessible, reasonably lit and free from extremes of temperature and draughts.
Do not mount the thermostat on an outside wall, above a radiator or in a location where it may be subjected
to direct sunlight.
To ensure trouble free reception for the Radio Controlled Clock (RCC),
always ensure that the programmable thermostat is mounted away
from any possible sources of interference (such as radios, TV sets,
computers, etc.), and is not mounted on or in close proximity to large
metal objects. Installing the ST620 in enclosed areas such as cellars and
basements is not recommended. There are only two electrical
connections required to the ST620, and these connections should be
made to the terminal block inside the programmable thermostat. No
Earth connection is required for the correct and safe operation of the
ST620, but a parking terminal is provided to connect an Earth wire if
one is present. These connections are shown in the drawing and table below:
Terminal Function
L (COM) Live
SL (NO) Switched Live (output)
Earth Earth Parking (No electrical connection)
NOTE: All electrical installation work should be carried out by a suitably qualified Electrician or other
competent person.
If you are not sure how to install this programmable thermostat consult either with a qualified
electrician, heating engineer or your boiler / heating system supplier for advice on how to continue.
