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Packaged rooftop units
21
Anti-freeze protection for low outdoor temperatures
(opcional equipment for GREAT COLD)
- Electrical heater for protecting the components of the electric panel.
This safety device is mandatory for an outdoor temperature lower
than -8°C WB. A reinforced electrical heater is mandatory for a
temperature lower than -16°C WB.
_
+
- Compressor with low-temperature protection using an additional
crankcase heater: mandatory for an outdoor temperature lower than
-8ºC WB. Activation temperature: -8ºC WB.
- Dampers for the mixing box (optional) with springs for automatic
closing in the case of a cut in power. Mandatory for an outdoor
temperature lower than -8ºC WB. Activation temperature: -8ºC WB.
- Electrical heater for anti-freeze protection of the mixing box dampers
(optional): mandatory for an outdoor temperature lower than -12ºC
WB. Activation temperature: -12ºC WB.
- Hot water coil circuit (optional) with anti-freeze technology based on
the water temperature: mandatory for an outdoor temperature lower
than -20ºC WB. This protection is made up of a circulation pump,
two probes inserted in the input and the output of the coil, as well
as an electrical heating for the piping layout.
Operation of the pump with GREAT COLD:
• Antifreeze protection: if the water temperature in the coil drops
below 4ºC, the control activates the pump and the 3-way valve
opens to 100%. The pump stops when 7°C are reached.
• Safety of minimum outdoor temperature: if the outdoor temperature
drops below 4ºC, the control activates the pump and the
3-way valve opens to maintain, in the water coil, a water outlet
temperature of 10ºC in ON operating mode and 15ºC in OFF
operating mode.
The electrical heater(s) is(are) activated when the thermostat
installed inside the electric panel detects that the temperature drops
below 5°C.
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 safety device is recommended in particular with gas burner.
It is installed in the factory in the auxiliary electric panel (except
in models 200 to 360 which do not include this panel). Automatic
reactivation.
Pressure reading is done thanks
to two intakes within the air
fl
ow before and after the
fi
lter,
such that a comparison is made
between the pressure of the inlet
air to the
fi
lter (positive) and the
supply air of the same to the
other side of the evaporating coil
(negative).
Refrigerant leak detector (optional)
The gas detector sensor is a device that signals leaks in refrigerant.
When the loss of a certain concentration is detected, the sensor sends
the alarm to the control, which stops the unit and locally activates a
acoustic and visual signal.
This offers the advantage of acting immediately to gas leaks,
guaranteeing the safety of persons who are in the proximity thereof.
Its installation complies with European regulations F-GAS, EN378,
and ASHRAE 15.
This sensor is installed next to the supply fan. In case of alarm, it is
reset manually.
Summary of Contents for 50EH
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