60
Note
■
Moving the control unit panel into the service posi-
tion:
See page 80.
■
Opening the programming unit:
See page 79.
C
B
A
F
AUTO
MAN
D E
Fig. 51
0
1.
Open any non-return valves installed on site.
0
2.
Check the pre-charge pressure of the expansion
vessel. Adjust the pre-charge pressure to match
the system conditions if necessary.
0
3.
Fill (flush) and vent the secondary circuit via an
on-site connection.
!
Please note
To prevent appliance damage, check the
secondary circuit flow and return connec-
tions on the appliance for
leaks
.
In the case of leaks, switch off the appliance
immediately, drain the water and check the
seating of the seal rings. Always replace
displaced seal washers.
0
4.
Check the system pressure at the pressure gauge.
Top up with water if required.
■
Minimum system pressure:
0.8 bar (80 kPa)
■
Permissible operating pressure:
3.0 bar (0.3 MPa)
0
5.
Move the control unit panel into the service posi-
tion.
0
6.
Open the programming unit.
0
7.
Slightly open quick-action air vent valve
B
; it
remains open.
Connect the on-site hose to secondary circuit air
vent valve
C
.
!
Please note
Escaping liquids can lead to electrical
defects.
Protect electrical components from escap-
ing liquids.
0
8.
Open secondary circuit air vent valve
C
.
Danger
Escaping hot water and hot steam can
cause serious injury and damage the heat-
ing system.
Only open drain and fill valves when the
heating system is cold.
0
9.
Move 3-way diverter valve
A
to its centre posi-
tion: Press
D
and turn anti-clockwise to lock to
the "MAN" position. Move lever
E
to a vertical
position.
Commissioning, inspection, maintenance
Filling and venting on the secondary side
(cont.)
5831412
