gis
•Hysteresis
The moment Tnet falls below (Tset - Tsolar diff - Hysteresis), the controller registers such a heat demand that the gas burner and the solar heating system jointly heat the water. The solar heating system is only employed when the temperature measured by S1 is a certain (adjustable) value grater than that of S2.
•Tsolar diff
When Tnet exceeds (Tset - Tsolar diff), the gas burner is shut off and the water is heated exclusively by the solar heating system. When Tnet rises above Tset (provided Tset = Tsolar limit), the solar heating system switches off. The value of Tsolar diff is adjustable (12.9.5 "Setting the solar difference").
•Tsolar limit
Preset (12.9.4 "Setting the solar limit temperature") water temperature at which heating via the solar heating system is stopped.
•
Graphical representation of heating cycle
Legend
A = Gas burner on
B = Gas burner offTsolar limit
Tnet:
•= no heat demand, so water
not heated
•= water heated via solar heating system
•= water heated via solar heating system and gas burner
Tset 
Solar diff.
t = time
T = Temperature
45 oC = Minimum tap water temperature
Hys.
Tmin = 45C
Note
Tnet can rise above Tset,. However, this is only possible if Tsolar limit is increased via the service menu.
Note
Tsolar limit can be lower than Tset; this will mean that Tnet can never be equal to Tset.
2.4Protection for the appliance
2.4.1Introduction
The electronic controller monitors the water temperature, helps ensure the safe use of the solar heating system, and ensures safe combustion. This takes place using:
•the Appliance water temperature protection
•the Gas valve
•the Fan
•the Pressure switch
•the Flame probe
Instruction manual SGE | 15 |
