Electronic Expansion Valve (Exv); Moisture Indicator; Filter Drier; Water Type Heat Exchanger - Carrier AQUASNAP 30RBM Series Installation, Operation And Maintenance Instructions

11.5 - Electronic expansion valve (EXV)

The EXV has a stepper motor and a sight glass which can be
used to check the mechanism movement and the presence of
the liquid gasket.

11.6 - Moisture indicator

Located on the EXV, enables control of the unit charge and
indicates moisture in the circuit.
The presence of bubbles in the sight-glass indicates an
insufficient charge or non-condensables in the system.
The presence of moisture changes the colour of the indicator
paper in the sight-glass.

11.7 - Filter drier

The role of the filter drier is to keep the circuit clean and moisture
free.
The moisture indicator shows, when it is necessary to change the
element.
A difference in temperature between the filter inlet and outlet
shows that the element is dirty.

11.8 - Water type heat exchanger

Brazed plate water type heat exchanger comprising two
refrigerating circuits.
The hydraulic connections of the heat exchanger are Victaulic
connections.
The water heat exchanger is thermally insulated with 19 mm
of foam rubber.
As an option it can be protected against frost by an electric
heater (water exchanger frost protection option).
Any products used for thermal insulation of recipients during
hydraulic connection must be chemically neutral to the
surfaces on which they are applied. All original materials
supplied by the manufacturer comply with this requirement.
NOTE - Monitoring in operation
• Follow local regulations on the monitoring of pressure
equipment
• The user or operator is usually requested to create and
maintain a monitoring and maintenance log.
• In the absence of any regulations, or in addition to the
regulations, follow the guidance in the EN 378 standard.
• Follow the local professional recommendations, whenever
they exist.
• Regularly check for the presence of any impurities (e.g.
sand, grit) in the heat-transfer fluids. These impurities
can cause wear and/or pitting corrosion.
• The reports of the periodical checks by the user or the
operator must be included in the monitoring and
maintenance log.
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11.9 - Refrigerant

Units running with R410A.

11.10 - High-pressure safety pressostat

The units are equipped with high-pressure safety pressostats
with automatic reset.
These pressure switches are located at the discharge of each
circuit.

11.11 - Variable frequency drive

The units are equipped with variable frequency drives to
control the fan speed within the fmin-fmax frequency range
(standard, fmin=5 Hz and fmax=50 Hz).
All fans on the same refrigerating circuit are controlled by a
single variable frequency drive. Fan speed is changed by
generating a controlled waveform in which frequency and
voltage are varied (Pulse Width Modulation).
Fan start-up/shut-down and the working range frequency
setpoint are controlled by the Controller through RS485
communication using the LEN Protocol.