Pressure Gauge; Safety Valve; Automatic Air Vent; Time Clock - Sime benchmark FRIENDLY FORMAT Installation And Servicing Instrucnions

and to fit a replacement vessel (of similar or greater capac-
ity) external to the appliance but as close as possible to the
C.H. return.
Alternatively the vessel can be replaced as follows.
Note replacement is not recommended if a rear flue outlet
is used or if the clearance above the casing is less than
300 mm.
– Remove the casing front panel as described in section 5. 1 .
– Isolate the C.H. flow and return valves (17 - 18 fig. 2),
and drain the appliance through the drain plug (13
fig. 2).
– Unscrew the expansion vessel pipe union at its connec-
tion union.
– Remove the screw securing the expansion vessel bracket
at the top, rear of the appliance.
– If a rear flue outlet is used it is necessary to disen-
gage the flue and air duct temporarily. Refer to sec-
tion 3.5.
– Remove the adjusting screws on the wall mounting brack-
et thereby allowing the appliance to move slightly for-
wards at the top.
– Lift the expansion vessel out of the appliance through
the top.
– Replace the expansion vessel and re-assemble in reverse
order. Re-pressurise and re-commission the system as
described in section 4. 1 .
8. 1 8

PRESSURE GAUGE

– Remove the casing front panel as described in section 5. 1 .
– Remove the two screws and pivot the control box down-
wards.
– Isolate the C.H. flow and return valves (17 - 18 fig. 2).
– Drain the appliance through the drain point (13 fig. 2).
– Unscrew the pressure sensor from the brass body near
the drain point.
– Squeeze the gauge to depress the retaining clips, then
ease the gauge forwards.
– Reassemble in reverse order.
Refill and re-commission the system as described in sec-
tion 4. 1 .
26
8. 1 9

SAFETY VALVE

– Remove the casing front panel as described in section 5. 1 .
– Remove the two screws and pivot the control box down-
wards.
– Isolate the C.H. flow and return valves (17 - 18 fig. 2).
– Drain the appliance through the drain point (13 fig. 2)
– Unscrew the union supporting the outlet pipe from the
valve, and remove the valve by unscrewing it from the
brass housing.
– Fit the new safety valve using a suitable jointing compound
and re-assemble in reverse order. Refill and re-commis-
sion the system as described in section 4. 1 .
8.20

AUTOMATIC AIR VENT

– Remove the casing front panel as described in section 5. 1 .
– Isolate the C.H. flow and return valves (17 - 18 fig. 2).
– Drain the appliance through the drain point (13 fig. 2).
– Unscrew the automatic air vent.
– Fit the new automatic air vent using a suitable jointing
compound and re-assemble in reverse order. Refill and re-
commission the system as described in section 4. 1 .
8.21

TIME CLOCK

– Remove the casing front panel as described in section 5. 1 .
– Remove the two screws and pivot the control box down-
wards.
– Open the plastic driver control box housing by removing the
room thermostat cover (one screw) and the single central
fixing screw then prising open the four locating tabs.
– Pull off the electrical connections at the back of the clock.
– Remove the four screws securing the plastic frame of the
time clock to the fascia panel.
– Remove the plastic frame and pull out the time clock.
– Re-assemble in reverse order and test the operation of
the new clock.
Set it to the desired settings as described in section 4.3