Maintenance
36
3 A small quantity of water will remain in the
d.h.w. heat exchanger after draining. If the
boiler is being drained to prevent freezing, the
d.h.w. heat exchanger must be removed and
inverted to drain fully or an antifreeze solution
added.
26
Fig. 8.4
8.5
Combustion analysis check
If it is necessary to carry out a combustion analysis
remove the plugs indicated in Fig. 8.1.
Reference figures are given in the sections 4.3 or
4.4 of this manual.
8.6
Cleaning the condensing heat
exchanger and burner
To remove the burner---fan group D (Fig. 8.5):
1 Take off the front and side panels of the case.
2 Remove the sealed chamber lid.
3 Disconnect the connectors of the ignition elec-
trodes E and detection electrode F (Fig. 8.5).
4 Disconnect the rubber pipe G (Fig. 8.6).
5 Unscrew the gas connector H.
6 Loosen (do not remove) the screw I.
7 Remove the screws J and the air box K. Leave
the air box with the air hose clamped to the
water pipe.
8 Remove the nuts L (Fig. 8.5) and the burner---
fan group D.
E
F
L
L
D
Fig. 8.5
M
A
INTE
NANC
E
