O Expansion Vessels And Temperature-Pressure Gauge; Function; Checks; Removal Of The C.h. Expansion Vessel - Biasi RIVA COMBI Service Manual

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Third Part (edition-0106) Expansion Vessels and Temperature-Pressure Gauge
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Expansion Vessels and Temperature-
Pressure Gauge

1) Function

2) Checks

3) Removal of the C.h. Expansion Vessel

4) Removal of the D.h.w. Expansion Vessel
5) Removal of the Temperature-Pressure
Gauge
1 Function
The C.h. expansion vessel (A in Figure 1)
function is to allow for the volume expansion of
the c.h. circuit water due to the temperature rise.
The D.h.w. expansion vessel (B in Figure 1)
function is to allow for the volume expansion of
the d.h.w. circuit water due to the temperature
rise.
A
2 Checks
1) Empty the primary circuit of the boiler.
2) Remove the protective cap C (Figure 2) from
the valve on the top of the c.h. expansion
vessel and connect a suitable air pressure
gauge.
3) Check the pre-load pressure. It would be 14.5
psi.
RIVA COMBI SERVICE MANUAL – REV A
B
Figure 1
4) Remove the protective cap D (Figure 3) from
the valve on the bottom of the d.h.w.
expansion vessel and connect a suitable air
pressure gauge.
5) Check the pre-load pressure. It would be
50.75 psi .
3 Removal of the C.h. Expansion
Vessel
1) Remove the front panel of the case.
2) Loosen the screw E (Figure 2).
3) Loosen the screws F and unscrew the
connection G (Figure 4).
4) Unscrew the lock-nut H (Figure 4) and remove
the c.h. expansion vessel.
H
F
5) Re-assemble the parts in reverse order of
removal.
E
C
Figure 2
D
Figure 3
G
Figure 4
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