Carrier 50EN 415 Installation, Operation And Maintenance Instructions page 21

11 - SAFETY ELEMENTS
Clogged fi lter detector (optional)
Diff erential pressostat for detection of the fi lter clogging level.
The value for alarm signalling is set in factory, depending on
the fi lters selected for the unit.
The electronic control allows the settings selection for the
clogged fi lter alarm: only indication (by default) or unit stoppage.
Manual reset.
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).
This safety device is particularly
recommended with gas burner.
This pressostat is installed in the
factory in the main electric panel or in
the auxiliary electric panel (depending
on the model).
Remote alarm (optional)
CARRIERrtc control allows the management of a relay for
remote alarm signalling.
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 off ers 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.
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.
The electrical heater(s) is(are) activated when the thermostat
installed inside the electric panel detects that the temperature
drops below 5°C.
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● 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 as well as
two probes inserted in the input and the output of the coil
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.
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