Unical AIREX 25 2S, Installation And Servicing Manual

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31
Instructions for the installer
4.9 - WARNINGS
HOW TO AVOID CORROSION IN THE FIRE WOOD BOX
The use of wood with a high moisture content
(higher than about 25%)
and/or loadings not
proportioned to the system’s heat request
(long OFF periods with the wood storage full)
can cause considerable condensate formation
in the wood storage’s internal wall.
Check, once a week, the internal steel walls of the fire box.
They must be covered by a slight layer of opaque coloured,
dry tar, with bubbles inclined to break and fall off.
On the contrary, if the tar is bright, runny and, if removed with
the fire stoke, some liquid appears, it is necessary to use wood
with a lower moisture content and/or reduce the quantity of the
wood when loading the boiler.
If, in despite of these interventions the tar does not dry, you
must inform the local After Sales Service of this.
The condensate inside the fire box causes the corrosion
of the steel plates.
Corrosion is not covered by the guarantee, because it is
caused by a bad use of the boiler (wet wood, excessive
loadings, etc.).
CORROSION IN THE FLUE CIRCUIT
The flue is rich in water steam, due to combustion and the use
of wood which always retains water.
If the flue comes into contact with relatively cold surfaces (with
a minimum temperature of about 60 - 70 °C), the steam water
condensates and in combination with other combustion
products originates corrosion phenomena of the metallic parts.
Every day check if there are signs of smoke condensation (black
liquid on the floor, behind the boiler). In this case you must use
a wood with a lower moisture content; check that the
recirculation pump is working correctly, the flue temperature
at part load, and increase the working temperature. To control
the room temperature it is therefore necessary to install a
mixing valve.
The corrosion caused by flue condensation is
not covered by the guarantee, because it is caused by the
wood’s moisture content and the way the boiler is used.
4.8 - CHECKS TO BE CARRIED OUT AFTER
THE FIRST START
CHECKING SEALS
During the initial start-up check the tightness
of the circuit and the connection to the
chimney flue. If there is any noticeable leaks
fumes alert the installer and / or our 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 thermostat, Te (32) at full
power (chapter 3.12) up to stop the fan.
Check for leaks from pipe connections.
After the initial start, at boiler off, open the lower door and
inspect the interior walls and finish of the door should be a
light color, indicative of proper adjustment of the air.
Otherwise, if the walls are blackened, it will mean a lack of
secondary air control (chapter 4.7 and 4.9).
GENERAL ADVICES
- Best performances are obtained after two/three days of
operation. Refractory material must be cooked and the tar
must encrust the top of the wood storage.
- The flame should have a good size and fairly fill the firebox.
- The flame should not be too red (default secondary air S).
- The flame should not be too blue (excess secondary air S).
- The flame should not be too noisy (excess primary air P).
- The flame must not be too small (default primary air P).
- If the ash does not go down well (increasing the primary air
P).
- If too much ash falls (decreasing primary air P).
- If the chimney smokes (open throughout the secondary air
S).
- If it continues to smoke (give max. secondary air, and
choking even the primary S P).
AIR ADJUSTMENT FAULTS
1) If the primary air is excessive a lot of ash and small pieces
of coal will fall through the slot into the combustion chamber.
The flame is too fast, dry, a cold colour and makes a noise.
The boiler is consuming a lot of wood and the door’s refractory
insulation is white.
2) If the primary air is insufficient the flame will be slow,
indecisive, influenced 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 of a dark colour.
3) If the secondary air is excessive the flame will be small, a
blueish 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 a red colour and not
transparent