34
MULTI ZONE system - with pump, room thermostat and ex-
ternal sensor.
TA
SE
TZ2
TZ3
TZ1
P3
RL1
SP
RL2
RL3
P2
P1
R
M
Fig. 32
6.14 Refilling or emptying
Before carrying out the operation described below, isolate the
boiler power supply.
Ensure that the inhibiter concentration is correct on refilling.
6.14.1 Method of filling a sealed system
A sealed system must only be filled by a competent person us-
ing a method similar to that shown in figure below.
Stop
valve
Stop
valve
Test cock
Hose
unions
Double chech
valve assembly
Filling loop
temporarily connected
Mains
water supply
Heating
cicuit return
Fig. 33
6.14.2 SYSTEM Filling
Remove the front panel:
– remove the two screws (1), pull the front panel (2) forwards
and release it from the top by lifting it.
1
2
Fig. 34
Domestic hot water circuit:
– open the domestic hot water inlet isolation valve (4)
– open each of the DHW taps until air is expelled.
Heating circuit:
– open the isolation and air bleeding valves in the highest
points of the system
– loosen the automatic bleed valve (3)
– open the heating circuit isolation valves (8) and (9)
– activate the filling system "Method of filling a sealed sys-
tem", and fill the heating system until a pressure of
1-1.2 bar
is shown on the pressure gauge (5)
– stop the filling system
– check that there is no air in the system by bleeding all the
radiators and the circuit on the high points of the system.
Connect a suitable pipe and use the heat exchanger bleed
point (10) to vent the primary heat exchanger
3
8
5
4
9
Fig. 35
NOTE:
to completely remove all air from the system, it is rec-
ommended that this operation is repeated a number of times.
