Buderus 500 - 28/C Servicing Manual page 39

box 49
Loosen by one turn the sealing cap on the automatic air
vent located on the top left-hand part of the boiler.
box 50
2
1
Key to terms:
1 = CH flow
2 = DHW outlet (combination boilers only)
3 = Gas connection
4 = MCW inlet (combination boilers only)
5 = CH return
Connect the hose (item 6) to the drain cock of the boiler.
Open the filling and draining cock and drain the heating
system, see box 53.
box 51
Fit the casing and use the radiator key to turn the casing
lock to "closed".
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
4
3 5
box 52 Filling the system and venting it of air
Turn the operating switch on the boiler to position "0"
(OFF), see box 43.
Remove casing, see box 47.
box 53
stop
valve
DHW
cold
Connect filling loop (accessory), see box 50, item 6.
Open both stop valves.
Fill the system to a pressure of approx. 1.5 bar.
Shut both stop valves.
Disconnect the filling loop.
Vent all radiators from air starting with the lowest radiator
and working your way up to the highest point.
6
Check the pressure after venting. If the pressure has
dropped under 1.0 bar then top up the system as
described previously.
Disconnect the filling loop and cap off.
box 54
Turn the mains switch to "ON".
Actions
stop
valve
double
check
valve
filling loop
CH
return
Buderus Ltd. • http://www.buderus-domestic.co.uk
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