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9. S
AFETY
ELEMENTS
Clogged fi lter detector (optional)
Differential pressostat for indication, through an automatic reset alarm,
of a level of dirtiness of the
fi
lters greater than the established level.
This pressostat is installed in the factory in the indoor unit.
Control of air fl ow (optional)
A differential pressostat can be incorporated in order to measure the
variation in air
fl
ow. This pressostat allows the detection of fan belt
breakages, since the fan relay only detects operating faults that have
arisen in the motor. This safety device is included in units with electrical
heaters. This pressostat is installed in the factory in the indoor unit.
10. O
PTIONAL
Conde nsat ion pre ssure c ont rol (38HB/HF)
This control is advisable for outdoor units 38HB/HF that work in cooling
with an outdoor temperature below 15ºC.
In units with centrifugal fan a check is performed per damper in the fan
supply. A servomotor opens or closes the damper depending on the
proportional signal 0-10V received from the electronic control system.
V-220004
Damper
Servomotor
The installation of some of these options brings in pressure
drops at air level therefore this must be considered when
selecting fans.
The pressure drop graphs in the options, can be seen in the
technical brochure.
High pressure pressostat
Connected to the compressor discharge, it will
stop its operation when the pressure at that point
reaches the setpoint. It disconnects at 42 bar and
it is automatically reactivated.
Low pressure pressostat
When connected to the compressor suction, it
will stop its operation when the pressure at that
point goes down below the tare value (caused
by obstructions in the circuit, excessive dirt in the
fi
lters, fan stop or ice formation in the evaporator).
This pressostat disconnects at 2 bar and is automatically reactivated.
Safeties at the compressor
The scroll type compressor that these units as standard have the
following safeties:
- Non-return valve built into the compressor.
- Temperature probe for the discharge from the compressor to protect
the unit with discharge temperatures greater than 135ºC.
Defrost control
This safety device is intended to eliminate ice which could accumulate in
the outdoor coil when the unit is working in the heating cycle. Defrosting
is carried out by the control depending on the value measured by the
sensor(s) on the outdoor coil(s) and the time set between defrosting
operations.
Magnetothermals for line protection
They are located at the beginning of the power lines for the
compressor(s) and motor fan(s) to protect them.
Automatic switch in the control circuit
Magnetothermal switch that protects the operation circuit against
continuous surges as well as against high currents of short duration
(short circuits).
Main door switch
By using a mechanical device, it impedes access to the electric panel
when the unit is with voltage.
Anti-fi re safety
With the optional return air probe, the electronic control can activate an
anti-
fi
re safety device that detains the unit when the return air surpasses
a temperature of 60°C (by default). It cannot return to operation until
the temperature has dropped to below 40ºC.
Split-system cooling units
and heat pumps
12