Unical AIREX 25 2S, Installation And Servicing Manual

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Instructions for the installer
4.11 - SUMMER OPERATION
Use of the boiler in summer for the production
of only domestic hot water is not advised, unless
you follow these rules meticulously:
1) Use very dry wood
2) Do not load the boiler with too much wood,
load the boiler partially, 2 or 3 times per day
according to need.
Important.
It is absolutely wrong to load the boiler
completely so as to gain very long working
periods (for example 24 hours). Doing so the
boiler (when the fan is OFF) will produce a lot
of acid condensate and corrode the fire box.
4.10 - THERMOSTAT ADJUSTMENT
WOOD FIRED BOILER
The boiler’s adjustment thermostat must be set
to the desired temperature (the adjustment
range,
limited by stoppers that must not be removed,
varies from 75° to 85°C).
To adjust the boiler’s flow temperature to the heating system it
is necessary to foresee the installation of a 3 or 4 way mixing
valve.
If this mixing valve is not installed the guarantee will be
void.
The manual reset safety thermostat, pos. 31, complies to the
regulations in force.
At the start-up stage check if it has to be reset.
To do this unscrew the plastic protecting cap and press the
reset button; then replace the plastic cap.
If the boiler safety’s thermostat has to intervene frequently,
pos. 31, reduce the setting temperature of the working
thermostat (pos. 32 on the control panel).
If this problem is repeated, inform the local After Sales Service.
PRECAUTIONS TO BE TAKEN DURING BOILER
OPERATION
After every air adjustment , wait 5 to 10 minutes before making
a new adjustment. Once the best adjustment has been
established, at the end of the day check that the surfaces of
the combustion chamber and the door insulation are of a white
colour.
In the ash deposited in the cradle there must be only a few
unburnt embers. If the primary air is in excess, in the ash there
will be embers and small pieces of coal, the flame will burn
fast, dry, have a cold colour and be noisier, and the output will
be excessive (paragraph 6.7).
If the primary air is insufficient the flame will be slow, small, it
will not touch the lower cradle and will drag little ash; the output
will be insufficient.
If the flame is a dark orange colour, the secondary air is
insufficient and the surfaces of the combustion chamber will
not be a white colour; if it is small and blue there is too much
secondary air.
Always open the upper loading door and the internal antismoke
flap slowly.
If, in despite of these precautions, some blow back will occur,
it will be necessary to use bigger pieces of wood, with a higher
moisture content, and to check that the boiler does not remain
unused for a long time (reduce the primary air - paragraph 6.7)
and make sure that the possible distortion of the cast iron fire
bars or the modification of the stainless steel grates or that the
presence of extraneous bodies (nails, metallic pieces) has not
obstructed the refractory burner’s slot.