Ravenheat CSI 85 - Manual (Page 38)

Fig. 58
38
7.25 TO REMOVE/REPLACE THE CENTRAL
HEATING EXPANSION VESSEL (fig. 58).
In the unlikely event of failure of the central
heating expansion vessel it is recommended
a suitable expansion vessel be fitted
external to the boiler. It should be positioned
on the return pipe and as close to the boiler as
possible. However, if it is necessary to replace
the central heating expansion vessel the
boiler must be removed from the wall as
follows.
7.25.1 Remove the casing (sect. 7.3) and lower the
instrument panel and remove the control box
cover.
7.25.2 Close the on/off valve on the domestic cold
water, central heating and gas supply.
7.25.3 Drain domestic water from the lowest hot
water tap and drain point on DHW inlet cock
(Fig. 45).
7.25.4 Drain the boiler.
7.25.5 Disconnect all pipework connected to boiler.
7.25.6 Disconnect mains cables and any other
connections (room thermostat, programming
clock).
7.25.7 Remove the duct.
7.25.8 Remove the 2 top coach bolts then remove
the boiler by lifting from the wall bracket.
7.25.9 Unscrew the nut that connects the expansion
vessel and remove it.
7.25.10 Remove the screw and the bracket supporting
expansion vassel.
7.25.11 Replce in reverse order.
7.24.1
TO REMOVE/REPLACE DHW
DIVERTER VALVE (fig. 57).
7.24.1.1 Remove front and bottom of the casing
(sect 7.3).
7.24.2 Close the on/off valve for the DHW circuit
and drain the boiler.
7.24.3
Remove the flow detector.
7.24.4
Unscrew the DHW diverter valve.
7.24.5 Replace in reverse order.
NOTE: Always use new o-rings.
7.26 TO REMOVE / REPLACE D.H.W. HEAT
EXCHANGER.
7.26.1 Remove the front panel from the outer
casing and lower the instrument panel
(sect. 7.3).
7.26.2 Close the on/off valves for the heating circuit
and the hot water circuit. Drain the boiler (Fig.
45) and drain hot water from the lowest hot
water tap and drain point on DHW inlet cock.
7.26.4 Unscrew the two screws that connect the DHW
heat exchanger and pull it out from boiler.
7.26.5 Replace in reverse order always use new
seals.
7.26.6 Fill the boilers as described in (sect. 6.4 and 6.5)
and check for leaks.