Installing The Aux Thermostat; Filling The System - Piazzetta P963 THERMO Instructions For Installation, Use And Maintenance Manual

5.5 INSTALLING ThE AUx ThERMOSTAT

The AUX thermostat activates an output from the electronic control board at 230 V when a certain settable SET temperature is reached (see "USE").
If the temperature of the water in the boiler read by the electronic sensor is higher than the AUX THERMOSTAT SET point temperature, the ends of the
cable connected to the Y terminal will be powered at 230 V.
Ensure that connection is made to installations with continuous current absorption of no more than 1A.
Connect the AUX thermostat using a 2x1 mm² cable secured with a PG7 cable gland, to be inserted in the hole (4) made in the rear panel of the
appliance (Fig. 36).
a
The AUX thermostat operates at 230 V, so take all due precautions when installing.
- Installation must be carried out by authorised personnel.
- To connect the AUX thermostat to the electronic control board, see the wiring diagram.
To install, proceed as follows:
- disconnect from the electricity supply;
- remove the right side panel (see "REMOVING THE CLADDING");
- remove the knockout to be found in the rear panel (pos. 4 - Fig. 36);
- insert the thermostat cable into the cable gland PG7 and then insert the gland into the hole that has just been made in the rear panel (Fig. 36);
- connect the cable terminal of the auxiliary device to the 2-PIN terminal of the electronic control board, see "WIRING DIAGRAM";
- refit the panel, following the above steps in the reverse order;
- check that the cable cannot come into contact with hot parts during appliance operation.

5.6 FILLING ThE SySTEM

a
Fill the water heating system when the appliance is shut
down.
a
Under no circumstances light the appliance if the boiler is not
full of water.
Sequenza di riempimento dell'impianto:
- open the air valves of the radiators;
- loosen the screw (18) of the automatic air or bleeder valve of the
appliance and leave it loose (Fig. 41);
- ensure that the drain tap (19) of the boiler is closed (Fig. 41);
- open the ball valves installed on the appliance "R" - "M" fittings;
- open the shut-off devices in the system;
- gradually open the relative tap located on the water heating system to
fill with water from the mains supply;
- bleed the system through the air valves installed in the system, on
the radiators and in the appliance, checking that they are working
properly;
- close the radiator air valves as soon as water starts to come out
(the screw of the automatic air valve of the appliance must remain
loosened);
- bring the installation up to working pressure, checking the value
on the manometer installed on the exterior of the appliance (see
"TECHNICAL DATA" and "WATER PIPE CONNECTIONS");
- close the mains water filling tap;
- check the joints for leaks and that the water heating system pressure
is stable;
- bleed the circulator (11) using the relative central screw (Fig. 41).
Characteristics of the mains water supply.
- The pressure of the mains water supply to the heating system must
be between 1 - 2 bar (in the case of higher pressure, install a pressure
reducer).
- The hardness of the supply water affects heat exchanger operation.
Fig. 41
In the case of excessive hardness (above 20°f) install a water-softening
device between the mains outlet and the appliance.
Every municipality provides water analyses free of charge.
Combination with another heat source:
- In the case of combination with another heating appliance, for
example a gas-fired wall boiler, to work in all safety it is advisable to
separate the circuits by installing a storage tank and a water cut-off
device (see the typical water circuit arrangement with auxiliary wall-
mounted boiler).
H07027850 / DT2000931 – 01
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DT2012106-01
DT2012108-01
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DT2033295-00
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