Installation and servicing instructions for wall-mounted condensing gas boiler Buderus 600 - 11R/19R/24R • 02/2006
55
Subject to modifications resulting from technical improvements!
Buderus • http://www.buderus-domestic.co.uk
Servicing
5
5.3
Checking and replacing parts
5.3.1 Checking the flue gas thermostat
z
Detach plug-and-socket connection on cable to flue
gas thermostat. Ensure that no cable is earthed
(grounded) at any point.
z
Allow the flue gas thermostat to cool down. Activation
temperature: Buderus 600 - 11R / 19R / 24R: 105 °C
z
Check flue gas thermostat for continuity. If continuity
is not present, the flue gas thermostat is defective.
z
Replace any flue gas thermostat found to be defec-
tive. Ensure you use only genuine Buderus spare
parts.
z
If the flue gas thermostat is working correctly, plug it
in once more.
5.3.2 Replacing the flue gas thermostat
z
Unscrew the flow-backup mounting.
z
Detach the cable plug at the flue gas thermostat.
z
Loosen both retaining screws on the flue gas thermo-
stat.
z
Remove the flue gas thermostat and replace with a
new unit (fig. 48).
z
Retighten the retaining screws.
z
Reconnect the cable plug.
z
Screw the mounting into place.
5.3.3 Replacing the UBA
z
Disconnect the system from the power supply.
z
Loosen the two screws on the UBA (fig. 49, item 1).
z
Carefully turn the UBA around with the backside
facing up (fig. 50).
z
Note the position of the cable plugs, disconnect all
cable plugs.
z
Fit a new UBA.
z
Reconnect all plug-in cables to their correct sockets.
z
Turn the UBA around and place back onto the
bracket.
z
Tighten the two screws.
z
Connect system to mains power supply.
Fig. 48 Buderus 600 - 11R / 19R / 24R :
replacing the flue gas thermostat
Fig. 49 Replacing the UBA
1
Fig. 50 Backside of the UBA
