14
Checking the expansion vessel and system pressure
Documentation of the expansion
vessel manufacturer
Note
Carry out this test on a cold system.
Expansion vessel
1.
Drain the system until the pressure
gauge indicates "0" or close the cap
valve on the expansion vessel and
reduce the pressure in the expansion
vessel.
Note
The pre-charge pressure of the
expansion vessel (p
0
) is made up of
the static system pressure (p
St
)
(= static head) and a supplement
(p
0
= p
St
+ supplement).
The supplement is subject to the set-
tings of the high limit safety cut-out.
For a high limit safety cut-out setting
of
■ 100 °C: 0.2 bar (0.02 MPa)
■ 110 °C: 0.7 bar (0.07 MPa).
2.
If the pre-charge pressure of the
expansion vessel is lower than the
static system pressure, top up with
nitrogen until the pre-charge pres-
sure is 0.1 to 0.2 bar (0.01 to
0.02 MPa) higher.
The static pressure corresponds to
the static head.
3.
Top up softened water
*1
until the
charge pressure of the cooled system
is 0.1 to 0.2 bar (0.01 to 0.02 MPa)
higher than the pre-charge pressure
of the expansion vessel.
Permiss. operating pressure: 5 bar
(0.5 MPa)
*1
For water quality requirements, see page 22.
Commissioning, inspection, maintenance
Further details regarding the individual steps
(cont.)
5692 701 GB
Summary of Contents for VITOPLEX 100
Page 31: ...31 5692 701 GB...
