Buderus 500 - 28/C Servicing Manual page 73

box 274
Fit new plate heat exchanger.
Renew the four O-rings if necessary.
Refit the plate heat exchanger and secure with the two
screws.
Open the cold water service valve.
Open the hot water tap in order to clean the new plate heat
exchanger (inside).
Close the hot water tap.
Fill the heating system, see box 52.
Fit the casing and place the boiler into operation,
see box 51, 54 or 55.
box 275 Replace the pressure relief valve
Take the boiler out of operation and drain the heating
system, see box 48 to 50.
box 276
1
2
Remove the stop spring (item 2) of the pressure relief
valve.
Remove the pressure relief valve (item 1) in the direction
of the arrow.
box 277
Release the pressure relief valve from the section of
condendsate outlet pipework by pulling in the direction of
the arrow.
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 278
Fit the new pressure relief valve and all other components
by following the above procedure in reverse.
Fill the heating system, vent it of air and place the boiler
into operation, see box 52 to 58.
box 279 Replace the turbine flowmeter
Remove the stop spring.
box 280
Use a screwdriver to lever out the turbine flowmeter.
box 281 Replace the DBA control panel
H
DANGER OF FATAL ACCIDENT
due to electric shock
Take the boiler out of operation and remove the DBA
control panel, see box 43, 44, 47, 63 or 70.
Buderus Ltd. • http://www.buderus-domestic.co.uk
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