Technical data

6 720 611 443 GB (03.11)
24
Commissioning
5.1 Commissioning
Benchmark Water Treatment: For optimum perform-
ance after installation, this boiler and its associated cen-
tral heating system should be flushed in accordance
with the guidelines given in BS 7593:1992 - Treatment
of water in domestic hot water systems. Full instructions
are supplied with proprietary cleansers sold for this pur-
pose. If an inhibitor is to be used after flushing, it should
be used in accordance with the inhibitor manufacturers
instructions.
To drain the appliance shut the system valves and open
the system drain point.
Suitable flushing agents and inhibitors are available
from Betz-Dearborn Tel: [phone] and Fernox
Tel: [phone]. Instructions for use are supplied
with the these products.
B Before commissioning, the gas supply pres-
sure must be checked at the gas supply pres-
sure test point (see page 6, fig. 2, item 7).
Natural gas appliances must not be operated if
the gas supply pressure is below 18 mbar or
above 24 mbar. LPG appliances must not be
operated if the supply pressure is not 37 mbar
at the inlet to the appliance.
B Unscrew the condensation trap (358) and pull out, fill
with approx. 1/4 l of water and refit. Refer to fig. 32.
B Adjust charge pressure of expansion vessel to static
head of the central heating system (see page 27).
B Open all system radiator valves.
B Check automatic air vent is open (27) fig. 32
B Turn on service valves (170), fill central heating sys-
tem to pressure of 1 - 2 bar through the WRAS
approved filling loop. Refer to fig. 32.
B Vent radiators.
B Refill heating system and set the pressure to 1 bar.
B Turn on cold water service cock (173). Refer to
fig. 32.
B Check that the gas type specified on the identifica-
tion plate matches that of the gas supply.
B Turn on gas cock (172). Refer to fig. 32.
5.2 Switching the appliance on/off
Switching on
B Switch on the appliance at the master switch (I).
The indicator lamp shows green and the display will
show the central heating flow temperature, when the
appliance is operating in the central heating mode.
Fig. 33
The trap filling programme ensures that the condensa-
tion trap is filled after the appliance has been installed
or after the appliance has been out of use for a long
period or the mains supply has been interrupted. For
that reason, the appliance remains at minimum heating
output for 15 minutes.
Switching off the appliance
B Set the master switch to (0).
The green indicator lamp goes out.
5.3 Switching on the central heating
The central heating flow temperature is adjustable
between 35°C and 88°C. Refer to table 13, page 27.
B Turn the temperature control to set the flow tem-
perature to a level appropriate to the type of central
heating system:
–Underfloor heating: e.g. setting “3”
(approx. 50°C)
–Low-temperature heating: setting “E”
(approx. 75°C)
Never run the appliance when empty or
unpressurised.
i
The operational CO
2
level is set at the fac-
tory and no adjustment is necessary when
installing a natural gas fired appliance.
i
If the display alternates between -II- and
the central heating flow temperature, the
trap filling programme is active.
B Always disconnect the appliance from
the power supply (fuse, circuit breaker)
before carrying out any work on the
electrical systems or components.
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