FCU 500, FCU 505 · Edition 02.17
45
Valve proving system
tL = P59
tM = P56
+
–
tL = P59
tM = P56
pZ >
pu
2
+
–
V2
OK
pZ >
pu
2
V1
OK
V1
V2
OK
V1
V1
V1
OK
V2
V2
V2
V1
V2
pZ >
pu
2
+
–
pZ >
pu
2
+
–
tL = P59
tM = P56
V1
V1
tL = P59
tM = P56
V2
V2
pZ >
pu
2
+
–
tL3 = P55
V3
Vp2 OK
Vp1
OK
pZ >
pu
2
+
–
tL = P59
tM = P57
V1
V2
V3
V1
Vp2
Program
A
Program
B
Program
A
Program
B
Vent V
p2
Test of valve 1
V
p1
Test of valve 2
V
p1
Test of valve V3
and
burner-side
valves
V
p1
+ V
p2
Wait for 1 s
END
START
Checking the first and second test volumes
(V
p1
+ V
p2
)
To check the test volume V
p2
, relief valve V3 is closed
and valve V2 is opened. The two test volumes V
p1
and
V
p2
are connected to each other. After a waiting time
of 1 s, valve V1 opens for the opening time t
L
set in
parameter 59. Valve V1 then closes and the measure-
ment time set in parameter 57 starts to elapse, see
page 110 (Measurement time V
). After the
measurement time has elapsed, the tightness control
checks pressure p
Z
. If p
Z
< p
u
/2, the test volume V
p2
is
leaking (relief valve V3, the burner valves or the pipe-
work are leaking). If p
Z
> p
u
/2, test volume V
p2
has been
successfully checked for tightness.
Valves V1, V2 and V3, the burner valves and the pipe-
work are tight.
