Servicing
5
Installation and maintenance instructions for wall-mounted condensing gas boiler 600 - 11S/19S/24S/24C • 02/2006
45
Subject to modifications resulting from technical improvements!
Buderus • http://www.buderus-domestic.co.uk
5.3
Checking and replacing parts
5.3.1
Checking the flue gas sensor
z
Detach plug-and-socket connection on cable to flue gas
sensor. Ensure that no cable is earthed (grounded) at any
point.
z
Allow the flue gas sensor to cool down.
Activation temperature:
600 - 11S / 19S / 24S / 24C: 105 °C
z
Check flue gas sensor for free throughput. If throughput is
not free, the flue gas sensor is defective.
z
Replace any flue gas sensor found to be defective.
Ensure you use only genuine Buderus spare parts.
z
If the flue gas sensor is working correctly, plug it in once
more.
5.3.2
Replacing the flue gas sensor
z
Unscrew the flow-backup mounting.
z
Detach the cable plug at the flue gas sensor.
z
Loosen both retaining screws on the flue gas sensor.
z
Remove the flue gas sensor and replace with a new unit
(fig. 53).
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 crosshead screw (fig. 54, item 1) on UBA housing.
z
Swivel UBA housing downwards.
Fig. 53 600 - 11S / 19S / 24S / 24C:
replacing the flue gas sensor
Fig. 54 Swivel UBA housing downwards
1