Installation manual
1.0 Installation overview
1.1 Safety instructions
Make sure the mains supply to the thermostat is OFF before •
installation. If the thermostat is installed in a network, the 
mains supply to ALL thermostats in the network must be off!
As the EFIT 550 is not equipped with an earth terminal, the •
earthing screen of the heating cable and the earthing wire 
from the mains supply must be connected to the earth 
terminal in the surface mounted box or recessed metal box.
Do NOT use the EFIT 550 without a floor sensor when •
the heating element is installed under flooring with high 
thermal resistance.
The thermostat must not be exposed to moisture, water, •
and excessive heat.