Technical data
Technical documentation 
Technical documentation
STZS ed. 06/03
22
ZEUS SUPERIOR
ELECTRICAL CIRCUIT 
D.H.W. PHASE 
Operation 
When the main switch (IG) is in SUMMER or WINTER position, it powers the modulation board and 
enables operation in d.h.w. mode. 
When the temperature read by NTC d.h.w. sensor (NB) is below that set on the control panel (or on the 
CAR if fitted), the adjustment circuit starts the pump (MP) by means of the contact of relay K2. 
The circulation of water causes the pump pressure switch (SP) to close and, because this is connected in 
series with the NC contact of the flue pressure switch (SV), the coil of relay K5 is energised. 
Meanwhile, the adjustment circuit causes the deviation of the relay contact K3. 
This way, the motor (M) of the 3-way valve (VD) is powered and continues to operate until the limit 
switch "A" opens once the d.h.w. position has been reached. 
The low-voltage circuit excites the relay K5 and starts the fan (MV) commanding the relay K1. 
The consequent deviation of the flue pressure switch (SV) powers the relay K4 the contact of which, on 
closing, enables the control unit (IGN. UNIT) to start the ignition cycle, commanding first of all the 
ignition electrodes (E1-E2) and then, with the consensus of the overheating thermostat (TS), both the 
main coils of the gas valve (V/G). 
Ignition of the burner is detected by the control unit (IGN. UNIT) by means of the ionisation electrode 
(E3). 
Operation with Gaudium Magnum” 
When the Gaudium Magnum switch is in   position, the contact of the switch “IP” is closed. 
The solenoid valve EP and the lamp LP are powered when the main switch (IG) is “ON” position (SUMMER 
or WINTER) and the max d.h.w. flow limit (TP) thermostat switch is closed. 










