Ravenheat HE 25 S COMPACT, Instructions For Use Installation And Servicing

Page: 48 / 67

48
Fig.44
Fig.43
8.8 TO REMOVE/REPLACE EXPANSION
VESSEL (Fig.43)
Remove the front and bottom panels
(fig. 39-40).
Close the on/off valves for the heating
circuit and drain the water at the drain
point (fig.36). Unscrew the fixing
bracket and the nut connecting the
expansion vessel. Lift up the vessel
and remove.
Replace in reverse order. Use a new
gasket, taking care to ensure they are
replaced correctly.
8.9 TO REMOVE/REPLACE GAS VALVE
(Fig. 44)
Remove the front and bottom panels
(fig. 39-40).
Unscrew the nut at the top and the four
screws on the bottom of the gas valve.
Replace in reverse order.
IMPORTANT:
when the gas valve is re-fitted, check
combustion CO2 and adjust if
necessary (see section 6.9).
8.10 TO REMOVE/REPLACE PLATE HEAT
EXCHANGER (Fig. 44)
Remove the front and bottom panels
(fig. 39-40).
Remove the panel control box (sect.
8.22).
Close off the on/off valves for CH circuit
and DHW circuit and drain the boiler and
drain hot water from the lowest hot water
tap.
Unscrew the two allen screws that
connect the DHW heat exchanger and
pull it out from the boiler (fig. 46).
If necessary the pipes from the flow
manifold may have to be removed for
easier access. Lift up the plate heat
exchanger.
Replace in reverse order.
NOTE: Always use new O-rings.
8.11 TO REMOVE/REPLACE THE WATER
PRESSURE SWITCH (Fig. 46)
Remove the front and bottom panels
(fig. 39-40).
Close the on/off valves for the heating
circuit and drain the water at drain point
(fig.36).
Detach the wire connector, remove the
securing clip.
Replace in reverse order.
Fig.45