Buderus 600 - 11S Installation And Servicing Instructions page 50

5 Servicing
5.3.10 Replacing the pump
Disconnect the system from the power supply.
Shut the servicing valve.
Drain the 600 - 11S / 19S / 24S / 24C as per the
"Installation and Servicing Instructions".
Loosen the screw on the terminal box (fig. 66, item 2) of the
pump and open the terminal box. Note the wiring layout,
and loosen the cables (fig. 66, item 1).
Loosen the screw-in connections on the pump (fig. 66,
item 3) and remove the pump.
Fit new pump and connect to system.
Connect cables in previously-noted order inside terminal
box, close terminal box and screw shut.
Connect system to mains power supply.
Open servicing valves.
NOTE
Fill the 600 - 11S / 19S / 24S / 24C and purge
the system of air.
5.3.11 Checking the safety sensor
Unplug cable connection from sensor.
Measure resistance of sensor (fig. 67, item 1).
Use a second-reading thermometer to measure the
temperature around the sensor.
Compare readings with values shown intable 8 on
page 53. If there is any mismatch (i.e. > 5%), the sensor is
defective.
If the sensor is working correctly, plug it in once more.
Subject to modifications resulting from technical improvements!
50 Installation and maintenance instructions for wall-mounted condensing gas boiler 600 - 11S/19S/24S/24C • 05/2004
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Fig. 66 600 - 11S / 19S / 24S / 24C:
replacing the pump
Fig. 67 600 - 11S / 19S / 24S / 24C:
checking the safety sensor
Boulter Buderus Ltd. • http://www.boulter-buderus.co.uk
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