Buderus 600 - 11R Installation And Servicing Instructions page 58

5 Servicing
5.3.7 Checking the miniature fuses
Disconnect the system from the power supply.
Loosen the two fixing screws and carefully turn the
UBA around.
Check miniature fuses (fig. 57) for correct func-
tioning, or carry out visual inspection. If defective, fit
new fuse (1.25 AT).
Fuse Function
1 Glow ingitor
2 UBA, sensors, thermostat valve
3 UBA
Turn the UBA around and place back onto the
bracket.
Tighten the two screws.
Connect system to mains power supply.
5.3.8 Checking the safety sensor
Unplug cable connection from sensor.
Measure resistance of sensor (fig. 58, item 1).
Use a second-reading thermometer to measure the
temperature around the sensor.
Compare readings with values shown in table 6 on
page 60. If there is any mismatch (i.e. > 5%), the
sensor is defective.
If the sensor is working correctly, plug it in once
more.
5.3.9 Replacing the safety sensor
Shut the servicing valve.
Drain the Buderus 600 - 11R / 19R / 24R as per the
"Installation and Servicing Instructions".
Loosen the plug-in connection (fig. 59, item 1).
Unscrew the sensor (fig. 59, item 2) and replace with
a new unit.
Plug in cable connection.
Open servicing valves.
NOTE
Fill the Buderus 600 - 11R / 19R / 24R and
purge the system of air.
Buderus • http://www.buderus-domestic.co.uk
58 Installation and servicing instructions for wall-mounted condensing gas boiler Buderus 600 - 11R/19R/24R • 02/2006
Fig. 57 Checking the miniature fuse
Fig. 58 Buderus 600 - 11R / 19R / 24R:
checking the safety sensor
Fig. 59 Buderus 600 - 11R / 19R / 24R:
replacing the safety sensor
Subject to modifications resulting from technical improvements!
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