Specifications

8.18
Ghange ot
pump
8.18.1 Change
of complete
pump
Drain the appliance
as under 8.'l
and 8.1.2.
lsolate
the appliance
from the electrical
mains.
Open
the terminal
box of the
pump.
Note the
colour code
of
wiring and disconnect
pump
connection
cable.
Unscrew
the automatic air
vent
(Pl
)
by hand.
Mark and disconnect
the 2
control
lines of the
automatic
valve by unscrewing
the
tubing nuts
(P2).
Loosen
the 2
pump
unions
(P3)
and
unscrew
the bracket
fixing
screw
(P4)
and the
union
nut
(P5)
at
the right hand connection
to
the
main heat exchanger.
8.18.1.1 Open
flued boiler
Take
otf connection
to main heat exchanger
together with the
pump
as shown on fig. 75.
Reassemble in reverse order, using new
washer at the right
hand
connection
to
the
maln
heat exchanger.
Screw
in the automatic air vent by hand
only.
Check
-
earth continuity
-
polarity
-
resistance to earth
according
to INSTRUCTIONS
FOR
BRITISH
GAS MULTIMETER.
8.18.1.2
Balanced flued boiler
Unscrew
the upper
pump
union
(P3)
and spring
off the
pump
as
shown in
fig. 76. Reassemble in
reverse order, using
new washer at the right
hand connection
to the main heat exchanger.
Screw
in the automatic air
vent by hand
only.
Check
-
earth continuity
-
PolaritY
-
resistance to earth
according
to INSTRUCTIONS
FOR BRITISH
GAS
MULTIMETER.
5.
38