29
6.6 CHECKING THE COMBUSTION - CHIMNEY SWEEP MODE
As part of the Benchmark Checklist procedure the combustion levels of the boiler when the installation is
completed must be measured and recorded.
The air gas ratio of the boiler has been factory-set and should not require adjusting during commissioning. If
adjustment is recommended or required the engineer must be competent to carry out this work. See Fig. 6.3 for
analyser test point.
If the boiler requires adjusting or setting to operate on LPG, further guidance is detailed in Section 6.11.
Chimney Sweep Mode
Without any CH or DHW demand, press and hold the reset button for eight seconds and the boiler will fire at a fixed output.
The parasol and snowman (
) will flash at the same time to indicate this mode, if a Climatic controller is fitted it will
display ERR>07 code on the controller (this is not a fault).
Using the DHW up and down buttons you can change between three predefined output levels:
•
0%
(low fire)
•
80 - 90% (Max CH output)
Note:
CO
2
testing at this output is not required - % output depends on model and gas type
•
99%
(Max DHW output)
This mode will remain active for fifteen minutes or can be cancelled by turning the boiler off.
Use the DHW down button to set the output to minimum to check the minimum CO
2
reading, wait for the boiler stabilise,
check the combustion and record the reading.
Use the DHW up button to set the output to maximum to check the maximum heating CO
2
, again allow the burner to
stabalise and record the reading.
If the flow temperatures are getting up to maximum operating temperature during the procedure it is possible to open a hot
tap to lose some heat.
If the CO
2
readings are not within the stated tolerance (refer to Section 2.1) then check the installation including the complete
flue assembly and repeat the above process.
The CH up and down buttons can be used to increase and decrease the output in incremental steps if required.
When checking at maximum output the boiler will have a higher noise level, this is normal.
6.7 FINAL COMMISSIONING
1. Allow the heating system to heat up, then balance the system to achieve the necessary temperature
difference across the heating flow and return pipes at the boiler and check the system volume and pressure.
(Refer to Section 3.1).
2. Turn off the boiler.
3. Thoroughly flush out the water pipework (refer to Section 4.9). Clean the mains water inlet filter (see Fig. 5.4).
4. Refill and re-pressurise the system as described in Section 6.1.
5. Add the correct level of inhibitor to the system as detailed in the instructions supplied with the inhibitor.
6.8 FINAL ASSEMBLY
1. Raise the control panel and secure in position with the screws provided.
2. If the boiler is to be left in service with the User, set the controls, clock (if fitted, see User's Operating manual) and room
thermostat (if fitted) to the User's requirements.
3. If the boiler is not to be handed over immediately, close the boiler gas service cock and switch off the electrical supply.
4. If there is any possibility of the boiler being left during frost conditions, then the boiler and system should be drained
(refer to Section 8.2). It is recommended that a label is attached to the boiler drawing attention to the fact that the
system has been drained.
5. Complete the details of the installation in the Benchmark Checklist at the back of these instructions.
6.9 USER INFORMATION
The User must be advised (and demonstrated if necessary) of the following important points:-
1. How to light and turn off the boiler and how to operate the system controls.
2. The importance of annual servicing of the boiler to ensure safe and efficient operation and maintain the boiler
guarantee.
3. That any servicing or replacement of parts must only be carried out by a Gas Safe registered engineer.
4. Ensure that the boiler controls and room thermostat (if fitted) are set to the User's requirements.
5. Tell the User about the sealed system pressure.
6. Tell the User that if the electrical supply is on and the boiler has not operated for 24 hours for heating or hot water, the
pump will automatically operate for 30 seconds.
Alpha Evoke 28 and 33 - Commissioning
