Protecting The Unit From Frost - Hitecsa 117 Manual De Instalación, Uso Y Mantenimiento

II.6.5.3 Auxiliary thermal source
An auxiliary generator is a heat generator that runs alternatively to the heat pump; typically, it is a boiler. When the alternative generator is activated, the
heat pump and all its auxiliaries are off, even if powered. The auxiliary generator can be enabled only for heating the systems.
Operation of the auxiliary source
The auxiliary generator can be activated according to three modes:
- manually;
- for an outdoor temperature set point;
- for a convenience criterion based on the costs of electricity and fuel (methane and butane)
- for heat Pump malfunction.
System configuration for P0lPI0lP1 set up
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System configuration for ASP0lASPI0lASP1 set up
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II.6.6

PROTECTING THE UNIT FROM FROST

IMPORTANT!
If the master switch is opened, it cuts the power
supply to the plate exchanger heater and the
compressor crankcase heater. The switch should
only be disconnected for cleaning, maintenance or
repair of the machine.
When the unit is running, the control board protects the water side heat
exchanger from freezing by triggering the antifreeze alarm, which stops
the machine if the temperature of the sensor fitted on the heat
exchanger reaches the set point value and simultaneously maintains
the circulation pump active.
With the unit OFF but powered, if the water sensor on the outlet of the
heat exchanger detects a temperature lower than the antifreeze set-
point, it activates the circulation pump and the antifreeze resistance of
the heat exchanger and any pump heating resistance (RAE) accessory,
if present.
IMPORTANT!
When the unit is out of service, drain all the water
from the circuit.
IOM_EQUI PF-EQUHI PF_117a128_207983_200101_ES-EN-FR-DE-IT
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If the draining operation is felt to be too much trouble, ethylene
glycol may be mixed with the water in suitable proportions in order to
guarantee protection from freezing.
IMPORTANT!
Mixing the water with glycol modifies the
performance of the unit.
The use of ethylene glycol is recommended if you do not wish to drain
the water from the hydraulic system during the winter stoppage, or if the
unit has to supply chilled water at temperatures lower than 5°C The
addition of glycol changes the physical properties of the water and
consequently the performance of the unit. The proper percentage of
glycol to be added to the system can be obtained from the most
demanding functioning conditions from those shown below. Table "H"
shows the multipliers which allow the changes in performance of the
units to be determined in proportion to the required percentage of
ethylene glycol.
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Chiller
Inertial storage tank
Hydraulic circuit breaker
Boiler
Shut-off components not managed
Chiller
Inertial storage tank
Hydraulic circuit breaker
Boiler
Shut-off components not managed