20
NOTE:
The maximum burner pressure must be set first as this
can affect the minimum burner pressure setting. Refer to Fig. 33.
Turn all the temperature controls to
OFF
(or
MIN
) and the
programmer (if fitted) to
OFF
.
Turn off the gas and electricity supplies to the appliance.
12.4.5 Check the operation of the appliance.
Refer to the Operational Flow Diagrams, Section 16, for the
sequence of events.
The appliance control system gives priority to the satisfying of
the heatbank and the delivery of domestic hot water.
Check that all the system and radiator valves are open.
Set the hot water temperature control
MAX.
set the programmer
(if fitted) to DHW
ON
or
CONTINUOUS
.
Turn on the gas and electricity supplies to the appliance.
The boiler will light and follow the Tank Mode of operation until
the heatbank is satisfied (upto twelve minutes from cold) when
the burner will go off.
Fully open a hot tap to put the appliance into the DHW draw-off
mode. The burner will light to maintain the heatbank which is
supplying the hot water to the tap.
Shut the tap and the burner will go out, possibly after a short
period of time filling the heatbank.
Set the programmer, if fitted, to central heating
ON
, the hot
water temperature control to
MIN
, the heating temperature
control to
MAX
and the room thermostat to
MAX
. Check that
the system is pressurised , the burner will light and, after a
possible short period topping-up the heatbank, will supply heat
to the radiators.
Check that the radiators heat up evenly.
Balance the system so that the required temperature difference
across the heating flow and return pipes is obtained. See Section
3, Table 3.
Adjust the by-pass valve until the same temperature difference is
obtained. See Fig. 12. This should be carried out with only a
single radiator operating.
If thermostatic radiator valves are fitted then, ideally, one
radiator should be left uncontrolled.
The bypass valve should
never be fully closed
.
Set the room thermostat to minimum and check that the burner
goes out.
Reset the room thermostat to maximum and the burner will re-
light and follow the normal operating procedure.
12.4.6 Check ignition after a break in the gas supply.
Turn off the gas service cock and wait for 60 seconds. The main
burner and pilot will go out but sparking from the electrode will
continue. Carefully open the gas service cock and observe the
burner re-light and follow the normal sequence of operation.
Put the temperature controls (or Programmer) to
OFF
. Switch off
the gas service cock and the electrical supply to the appliance.
12.4.7 Drain and reset system.
Drain the heating system whilst the appliance is still hot. Refer to
Fig. 1. for the position of the appliance drain point.
Refill, vent and re-pressurise (sealed systems) as described previously.
Set the temperature controls to
MAX
. If a programmer is fitted
set to Continuous or 24 Hrs and the Heating to
ON
. The boiler
will fire and, when the heatbank is satisfied, commence to heat
up the radiators. Allow to operate for 45 minutes, venting as
necessary. Check for water soundness.
Note:
From cold it will take about 12 minutes for the heatbank to
be satisfied before the central heating system will receive heat.
IMPORTANT:
The complete system must be checked for water
leaks. Should any leaks be found they must be rectified before
proceeding further.
Set the temperature controls to
OFF
, or if a programmer is fitted,
switch to
OFF
. Switch electrical supply off at the mains.
Check for the correct operation of User’s Controls including the
room thermostat (if fitted).
12.5 COMPLETION OF COMMISSIONING.
Disconnect the pressure gauge and tighten the test point screw.
Re-start the appliance and check for gas soundness around the
test point screw.
Replace the burner pressure adjustment cover. Fix with the screw
and seal with suitable marking e.g. red paint.
Refit the expansion vessel and cabinet front panel. See Fig. 12.
If the appliance is being passed over to the User immediately
refer to Section 13, Users Instructions and set the controls to the
user’s requirements.
If the appliance is to be left inoperative check that the
programmer and the controls are set to
OFF
. Turn the gas service
cock to off and switch off the electricity supply.
For short inoperative periods leave the appliance under the
control of a frost thermostat, if fitted, or operating continuously
under the control of a room thermostat set at 6°C.
If there is any possibility of the appliance and system being left
inoperative during frosty conditions then drain the appliance
and system.
13.1
Tell the user how to operate the appliance and hand over the
Users Instructions leaflet and the completed
Benchmark
log book.
13.2
Tell the user what to do if the heating system is not to be
used in frosty weather. Also tell the user that if the appliance is
not to be used for long periods during frosty weather, the system
must be drained and the gas and electricity supplies turned off.
13.3
Tell the user the Sealed System set pressure if applicable.
13.4
Tell the user of the importance of regular servicing. Worcester
Heat Systems Ltd offer a comprehensive maintenance contract.
13.5
Set the system controls to the users requirements.
13.6
If an external programmer has been fitted instruct the user
how to set the programmes.
13.7
Tell the user about the safety devices and any hazard notices.
To ensure continued efficient operation of the appliance it
must be checked and serviced as necessary at regular
intervals. The frequency of servicing will depend upon the
particular installation conditions and usage, but once per
year should generally be adequate. The extent of the service
required by the appliance is determined by the operating
condition of the appliance when tested by fully qualified
engineers.
It is the law that any service work must be carried out by
competent engineers such as British Gas or Corgi registered
personnel.
14.1 PRE-SERVICE INSPECTION
Check that the flue terminal and the terminal guard, if fitted, are clear.
If the appliance is in a compartment check that the ventilation
14. Inspection And Servicing
13. Instructions To The User
Fig. 22. Facia Controls.
1
2
3
4
5
6
1. Power light.
5. Heating temperature contol
2. Heating demand light.
and reset control.
3. Hot water demand light.
6. Twin channel programmer
4. Hot water temperature control. (optional).
Summary of Contents for Highflow 400 BF
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