Servicing
5
58
Installation and servicing instructions condensing gas boiler 800 - 24/29/43/60 and 800 - 24T25/29T25 H/V • edition 02/2006
Subject to modifications resulting from technical improvements !
Buderus • http://buderus-domestic.co.uk
5.3.25 Replacing the control valve
z
Close maintenance isolating valves and drain the
800 Series.
z
Remove the control valve with a spanner and fit a new unit.
z
Fit regulating motor and lock into place by twisting the
bayonet connector.
z
Plug cable in.
5.3.26 Replacing the three-way valve
z
Close maintenance isolating valves and drain the
800 Series.
z
Loosen all screw-in tube connectors.
z
Remove three-way valve and fit new unit.
Refit screw-in tube connectors.
z
Fit regulating motor and lock into place by twisting the
bayonet connector.
z
Plug cable in.
z
Open maintenance isolating valves.
5.3.27 Checking the condensation-water bypass
z
Check to ensure that the condensation-water bypass is
connected.
fig. 86 Replacing the valve core on the 800 – 24/24T25/29/43/60
NOTE
Open the maintenance isolating valves and
then fill the 800 Series and purge the system of
air.
fig. 87 Replacing the three-way valve
Key to three-way valve:
A
hot water
B
heating
AB
boiler feed line
A
AB
B
NOTE
Fill the 800 Series and purge the system of air.
fig. 88 Function diagram of condensation-water bypass
NOTE
The device itself is fitted with an additional
condensation-water bypass (located on the
fume exhaust outlet).
