Buderus 500 - 28/C Servicing Manual page 61

box 201
Fit the new drive mechanism on the internal 3-way valve.
Ensure that the flat side faces upwards.
box 202
Connect the servomotor of the 3-way valve by following
the above procedure in reverse order.
Fill the heating system, vent it of air and place the boiler
into operation, see box 52 to 58.
box 203 Replace the internal 3-way valve
Take the boiler out of operation and drain the heating
system, see box 48 to 51.
box 204
1
2
3
Disconnect the cable from the main switch, see box 54.
Pull the spring off the flow NTC sensor lead (item 1).
Pull out the flow NTC sensor plug (item 2).
Pull the main switch cable out of the nut (item 3).
We reserve the right to make technical modifications
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C • Issued 02/2006
box 205
Remove the stop spring and 3-way valve-motor.
box 206
1 2 3
Pull the plug (item 1) out of the pump.
Loosen the four screws (item 3) on the pump.
Remove the return pipe with spring (item 4).
Remove the pipe to the expansion vessel with spring
(item 5).
Pull out the pump (item 2).
Buderus Ltd. • http://www.buderus-domestic.co.uk
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