Buderus GB162 User Instructions page 22

 Fill the heating system to a pressure of appx.
20 psi (1.5 bar). Read the pressure from the
pressure gauge on the pump group or on the
control panel of the BC10 (fig. 6).
The pressure in the heating system, which is
measured directly at the boiler, must be at least
equal to the required pre-pressure of the expansion
vessel plus 7 psi (0.5 bar). The minimum pressure
must not be less than 15 psi (1.0 bar) (if the heating
system is cold). The maximum pressure in the
I
heating system must not exceed 50 psi (3.5 bar).
NOTICE
It is very important that the heating
system is now purged, since all air will
collect at the highest point of the heating
system when the system is slowly filled
with water.
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Starting up the boiler
20 30
10
psi
110
100
90
Fig. 6 Reading the pressure gauge
130
110
150
120
90
P22
130
170
140 190
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