17
10 - SAFETY ELEMENTS
Location of the control and safety elements
30PA control
Device
Adjustment Symbol
Inlet water exchanger
probe
30PA
controller
B1
Outdoor air probe
B2
Oulet water exchanger
probe
B3
Compressor discharge
probe
B4
Refrigerant anti-freeze
probe on the exchanger
B6
Outdoor coil pressure
transducer
B7
Low-pressure pressostat 2 bar
LP
High-pressure pressostat 42 bar
HP
Connected to the compressor discharge, it will
stop its operation when the pressure at that
point reaches the setpoint. Disconnects at 42
bar and is reactivated automatically.
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). It disconnects at 2 bar and it
is automatically reactivated.
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).
Magnetothermal protection switches line
They are located at the beginning of the power lines for the
compressor and motor fan to protect them.
Main door switch
High pressure pressostat
Low pressure pressostat
Water anti-freeze protection
This safety device is built into the electronic control. This is activated
in COOLING mode when the water outlet temperature is lower
than the set value. This causes the stop of the outdoor fan and
the compressor.
Note: For operation with glycol water: consult.
Water circulation control
A di
ff
erential pressure switch detains the operation of the unit when
it does not detect water circulation.
Refrigerant anti-freeze protection
This safety device is built into the units' electronic control. It is
activated when, working in COOLING mode, the indoor refrigerant
temperature is lower than the setpoint value. This causes the stop
of the outdoor fan and the compressor.
Safeties at the compressor
The scroll type compressor that these units as standard have the
following safeties:
■
Non-return valve built into the compressor.
■
Thermal protection in the compressor, which stops the operation
of the motor when there is excessive heating.
■
Protection of the compressor discharge temperature through
a klixon.
By using a mechanical device, it impedes access to the electric
panel when the unit is with voltage.
Anti-freeze protection with heaters (optional)
Anti-freeze protection with
fl
exible electrical heaters around the
pipe lines of the hydraulic circuit to avoid their freezing. This
optional is recommended with negative temperatures.
Air coil
Differential
pressure
switch
Drain
bleeder
Plates
exchanger
B1
B3
B6
E
S
Compr.
B7
HP
LP
B2
Outdoor
air
B4
Sight glass
Expansion
valve
No-return valve
Liquid receiver (heat pump)
Summary of Contents for 30PA 180
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