Installation instructions
43
6.7 - COMBUSTION AIR
CONTROL
PRIMARY AND SECONDARY AIR
ADJUSTMENT
The AIREX boiler is equipped with a combustion
air intake fan (pos. 16 fig. 2), three combustion air
distribution manifolds (pos. 1 fig. 34) and regulators
of primary air (pos. P fig. 34) and secondary air
(pos. S fig. 34).
When commissioning the boiler, you need to adjust
the primary and secondary air, bearing in mind that the primary air
determines the boiler heat output and therefore the amount of
wood that is burned, and the secondary air completes the
combustion.
The following are the optimal adjustments of primary and
secondary air using good quality wood (beech) and low
moisture content (15%).
primary air
secondary air
pos.
pos.
AIREX 150
4
5
AIREX 200 & 200UK
4
5
For a proper air adjustment based on the type of wood used
and its effective moisture level, it is necessary to observe the
flame through the flame sight glass placed on the lower door.
The flame should fill about two-thirds of the lower combustion
chamber and gently caress the bottom cradle, without dragging
too much ash and without noise.
The flame will have an orange-pink-white colour, not too
transparent and with the centre tending towards blue.
To bring the flame to optimum conditions, you should then adjust
the primary air by turning the knob (pos. P).
Do the same for the secondary air (pos. S).
Example n.1
Wood difficult to burn (due to essence, shape)
S - Very closed (try to get the maximum dimension of the flame,
but not of a reddish colour).
P - Reasonably open in order to obtain a sufficient gasification.
6.8 - CHECKS TO BE CARRIED OUT AFTER
COMMISSIONING
CHECKING SEALS
During the initial start-up, check the tightness
of the smoke circuit and the connection to the
chimney. If there is any noticeable smoke
leakage, alert the installer and/or our After-Sales
Service. If there is any noticeable aspiration of
air through the door seals, tighten the handle
with greater force.
Check the proper operation of the panel board with the boiler at
full capacity until the fan is forced to stop when the set tempe-
rature has been reached.
Check for leaks from pipe connections.
After the initial start, with the boiler off, open the lower door and
inspect the internal walls and insulation of the door: they should
be of a light colour, indicative of a proper air adjustment.
Example n. 2
Very inflammable wood logs
S - Completely open.
P - Slightly closed in order to keep gasification reduced, but
sufficiently open to evacuate the ash that can close the
combustion head.
GENERAL ADVICE
- Better performance will be achieved after two or three days
of running. Refractory material must be cooked and the tar must
encrust the upper walls of the wood storage compartment.
- The flame should have a good size and fairly fill the combu-
stion chamber.
- The flame should not be too red (lack of secondary air S).
- The flame should not be too blue (excess of secondary air S).
- The flame should not be too noisy (excess of primary air P).
- The flame should not be too small (lack of primary air P).
- If the ashes do not go down well, increase the primary air (P).
- If too many ashes fall, decrease the primary air (P).
- If the chimney is smoky, open the secondary air (S) all the
way.
- If smoke continues to escape, open secondary air (S) to a
maximum, closing the primary air (P) partially as well.
AIR ADJUSTMENT FAULTS
1) If the primary air is excessive, a lot of ash and small pieces
of embers will fall. The flame is too fast, dry, has a cold colour
and makes noise.
The boiler is consuming a lot of wood and the door’s insulation
is white.
2) If the primary air is insufficient, the flame will be slow, hesitant,
affected by air currents and by the chimney draught, very small,
incapable of touching the lower cradle, with low ash production and
the door’s refractory insulation will be dark coloured.
3) If the secondary air is excessive. the flame will be small, of a
bluish colour and very transparent.
4) If the secondary air is insufficient. the flame will be big, it
will touch the lower cradle, it will completely fill the combustion
chamber and, above all, it will be of a red colour and not
transparent.
