Network installationIf more ECtemp 550 thermostats have been installed, theymay be connected in a network. If so, one of the thermo-stats is defined as the master unit controlling the time, dayof week and lowering of temperature during economy peri-ods for the other so-called slave units. This means thatchanges to these settings must be made on the masterthermostat and will then automatically take effect on all"slave" thermostats.Please contact the electrician to find out if the thermostatsin your house are linked in a network and, if so, ask whichthermostat is configured as master unit.2.1 Frost ProtectionHow to set the thermostat in frost protection mode1. Turn the button counter-clockwise un-til the temperature reaches +5°C (or 1if a scale from 1 to 10 is used).A frost symbol will now appear onthe display.ECtemp 5508 User Guide