Buderus 500 - 28/C Servicing Manual page 44

7 Actions
box 79
1
2
Twist (drawing 1) the fan in the direction of the arrow to
remove (drawing 2).
Check to see if the fan is soiled or wet.
Check to see if the fan impeller has come loose at the
motor spindle.
box 80
1
2
Loosen the three screws (item 1) on the gas valve.
Remove the gas valve (item 2).
We reserve the right to make technical modifications
44 Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C • Issued 02/2006
box 81
1
Remove the Venturi (item 1).
box 82
Fit the Venturi to the new fan.
box 83
1
Fit the gas valve to the new fan. When doing so, ensure
that the gas injector (item 1) is correctly fitted.
box 84
Fit the fan to the boiler. Remember to fit the new flat rubber
sealing ring (supplied) when doing so.
Fit the air silencer tube to the fan.
Fit the gas supply pipe to the gas valve. Ensure when
doing so that the flat rubber sealing ring is correctly fitted.
Insert the power supply plug into the gas valve, then insert
the power supply plug and tacho cable plug into the fan.
Open the gas cock and place the electrical system of the
boiler into operation, see box 59, 54 or 55.
Carry out a gas-leak check. Check the tightness of all
components that were loosened in the course of
component removal. Use an authorised foam-type leak
detection product for this purpose. If you detect a gas leak,
refer to box 46, 43 or 44.
Remedy the cause of the gas leak.
Open the gas cock, place the electrical system of the
boiler into operation and fit the casing, see box 59, 54, 55
or 51.
Buderus Ltd. • http://www.buderus-domestic.co.uk