Instructions To The User; Inspection And Service - Worcester 14/19CBi Installation And Servicing Instructions

13. Instructions To The User

Fig. 32. User controls.
1 2
1. Boiler demand
2. Burner ON
3. Lock-out
4. Temperature control knob/ ON-STANDBY/ Lock-out reset
13.1 Hand over the User Booklet and the Benchmark Log-book
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 (Sealed System)
pressure falls.
13.5 Explain that regular servicing, of a maximum of 12 months
between services, 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.
3 4

14. Inspection And Service

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 (Sealed
System) 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
Lift off the cap from the sample point on the top of the boiler and
connect the meter. Refer to Fig 30/30a.
With the appliance at maximum rate and stable expect readings
of about:
SHORT FLUE WITH
APPLIANCE
RESTRICTOR PLATE
CO
9/14CBi NG 0.003 - 0.007
LPG
0.003 - 0.007
0.002 - 0.005
14/19CBi NG
0.002 - 0.005
LPG
0.008 - 0.012
19/24CBi NG
LPG 0.005 - 0.010
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
Ensure that the gas and electricty supplies are isolated before
accessing the following parts.
Remove some or all of the following parts to gain access to the
components.
Outer Case. Loosen the screw and clip at the base, disconnect
the earth tag, lift the case up and pull forwards.
Base/Control Assembly. Remove the single screw and lower.
Refer to Fig. 33a/b.
Inner Case Door. Remove the two top corner screws. Loosen the
two bottom corner screws and lift the door off.
Combustion Chamber Front Cover. Loosen the two wing-nuts
and slide the 'J' bolts out of the slots. Pull the front cover
forwards and upwards to remove from the boiler.
NOTE: On the 9/14CBi the RHS bolt and clamping bracket must
be removed.
Fan - Integrated Rear Flue. Remove the combustion chamber
front cover. Carefully pull off the electrical connections and the
pressure tubes from the air flow detector. Slide out the fan and
flue hood assembly. Ensure that the combustion chamber rear
fits under the lip on the fluehood. To remove the fan, remove the
two fixing screws and release the clamping bracket.
Fan - External Flue. Remove the combustion chamber cover.
Carefully pull off the electrical connections and the tubes from
the air flow detector. Loosen the two clamps to remove the fan .
Refer to Fig 34.
Flue Hood - External Flue. Remove the fan, see above. Remove
the combustion chamber cover and withdraw the hood. When
refitting ensure that the combustion front fits under the lip of the
flue hood.
24
LONG FLUE WITHOUT
RESTRICTOR PLATE
FITTED FITTED
CO CO
2
7.2 - 8.1 0.002 - 0.005
8.1 - 8.7 0.002 - 0.005
6.6 - 7.5 0.002 - 0.005
7.8 - 8.5 0.002 - 0.005
7.1 - 7.7 0.008 - 0.012
8.0 - 8.9 0.008 - 0.015
CO
2
6.0 - 6.8
6.9 - 7.7
5.6 - 6.5
6.3 - 7.0
7.0 - 7.8
7.8 - 8.5