13.1 Hand over the User Booklet and explain how to operate the
appliance safely and efficiently.
13.3 Tell the user what to do if the appliance is not to be used in
very cold conditions.
13.4 Tell the user what to do if the system pressure falls.
13.5 Explain that regular servicing will maintain the safe and
efficient operation and extend the life of the appliance. WHS can
offer a comprehensive maintenance contract.
13.6 Tell the user that any work on the appliance must only be
carried-out by a competent person.
14.1 The extent of the service will be determined by the
operating condition of the appliance. It is the law that any
service work is carried-out by a competent person.
14.2 Inspection
Check that the terminal and the terminal guard, if fitted, are clear
and undamaged.
If the appliance is in a compartment or cupboard check that the
specified clearances are clear. Refer to Table 8.
Check all the joints and connections in the system and remake
any that show signs of leakage. Refill and re-pressurise as
described in Section 12-Commissioning.
Operate the appliance and take note of any irregularities. Refer to
Section 18-Fault Finding.
Check the combustion performance
Remove the cap from the sample point on the top of the
appliance and connect the meter. Refer to Fig 35.
With the appliance at maximum rate and stable expect readings
of about 6.5% - 7.00% CO2 and 0.002% CO.
Refit the sample point cap after the test.
Always test for gas soundness after the service has been
completed.
Disconnect the electrical supply at the mains and turn off the
gas supply at the gas service cock on the appliance before
starting any service procedures.
14.3 Component Access
Remove some or all of the following parts to gain access to
components.
Cabinet Front Panel.
Lift off the supports.
Facia.
Unscrew the two screws and lower. Refer to Fig 18.
Inner Casing.
Unscrew the four screws and remove. Refer to Fig 18.
Combustion Chamber.
Unscrew the two screws at the top.
Loosen but do not remove the two wing-nut extended screws at
the sides, unhook the clips and remove the chamber. Refer to Fig 41
and 42.
Fan.
Carefully pull off the electrical connections and the tubes
from the air flow detector. Unscrew the three screws to remove
the fan assembly. Refer to Fig 51.
Flue Hood.
Remove the fan. Unscrew the two screws at the front
and withdraw the hood. Ensure that the replaced hood passes
under the lip at the rear of the appliance.
Burner
. Remove the combustion chamber. Release the union nut
at the top of the gas valve. Carefully pull-off the connections to
the spark electrode and separate the in-line connector to the
flame sensing electrode. Refer to Fig 43 and 44.
14.4 Component Cleaning
Do not use a brush with metal bristles to clean components.
Clean the fan taking care not to block air flow detector.
Clean the burner to ensure that the blades and injector are clear.
Do not us a metal probe to clean the injector.
Clean the electrodes and check the alignment. Replace if there is
any sign of deterioration.
Clean the heat exchanger after covering the gas inlet tube.
Straighten any distorted fins on the heat exchanger.
Check the combustion chamber insulation and replace if there is
any sign of damage or deterioration. Refer to Section 15.4.5.
Carefully refit any components removed and check that all
screws are tight and the connections properly re-made with the
appropriate gaskets/O-rings.
Re-commission, as necessary, for correct operation to the users
requirements. Refer to Section 12 Commissioning.
Important:
Turn off the gas and electricity supplies and drain,
where necessary, before replacing any components.
15.1 Always check for gas soundness where relevant and carry-
out functional checks as described in Section 12-Commissioning.
Any O-ring or gasket that appears damaged must be replaced.
15.2 Component Access
Refer to Section 14.3 Inspection and Servicing for access to
components.
15.3 Draining the Appliance
Turn off the heating flow and return valves at the appliance.
Refer to Fig 16.
Remove the casing bottom panel by releasing it from the clips.
Fit a tube to each of the drain connections and open the taps.
Refer to Fig 47. Close the taps when the flow has stopped.
Important: A small quantity of water will remain in some
components. Protect any electrical components when removing
items that might retain water.
15.4 Component Replacement
Refer to Fig 41, 42 and 43 for the location of the components.
Replace any components removed from the appliance in the
reverse order using new gaskets/O-rings/sealant/heat transfer
paste where necessary. Always check that any electrical
connections are correctly made and that all screws are tight.
15. Replacement Of Parts
14. Inspection And Service
13. Instructions To The User
21
Fig.40 . User controls.
24SBi
System
pressure
gauge
C.H temperature control and
On/Off knob
Mains indicator
Reset button
