42
If there is any possibility of the boiler
being left during frost conditions,
then the boiler and system should
be drained. Alternatively, a suitable
antifreeze should be used.
To allow the boiler to be commissioned
and serviced correctly a combustion test
point is provided on the front cleaning
door.
The CO
2
and smoke test may all be
carried out using this test point.
The test point is not suitable for
measuring boiler efficiency or
conventional flue draught.
When using the test point on the
cleaning cover note that the flue gas
temperature reading will be higher than
that measured in the flue thus resulting in
an inaccurate efficiency reading.
To obtain an accurate flue gas
temperature and efficiency, the reading
can only be measured outside through
the low level flue terminal. For high level
and vertical balanced flues the reading
may be taken from the flue kit test point
provided . Refer to Section 2.3.
For Conventional flues, flue draught,
combustion and efficiency measurement,
a test point is provided in the
conventional flue connector section. See
Figure 9-5.
Commissioning
D
E
F
G
H
L
M
I
Figure 10-2:
15/21 air adjuster disc at position 'C'
CAUTION
!
NOTE
!
10.6 Air Adjuster disc - 15/21 only
To adjust the 15/21 air adjuster disc
when downrating - See Figure 10-2
1. Ensure the boiler is isolated from the
electrical supply.
2. Remove the burner from the boiler.
3. Undo the two screws and remove
the air inlet cover from the side of the
burner.
4. The secondary air shutter disc is
factory set in position ‘C’ – i.e.
with the cut-out marked C located
against the die-cast boss on the fan
housing - suitable for outputs of 18.3
and 21 kW only. See Figure 10-2.
5. Remove the screw from the centre of
the air shutter disc, and re-position
the disc such that the cut-out ‘B’
(corresponding to 15 kW output
setting – See Section 2.3) is located
against the cast boss on the fan
housing. Replace the screw in the
centre of the air shutter disc and
tighten.
6. Re-fit the air inlet cover to the side of
the burner and reassemble in reverse
order.
