II.10.2.5 Checks to be made while the machine is running
Intervention test: use
the system water gate
valves to reduce the
flow to the evaporator.
II.10.3 INSTRUCTIONS FOR FINE TUNING AND
GENERAL REGULATION
II.10.3.1 Calibration of safety and control devices
The units are tested in the factory, where they are also calibrated and
the default parameter settings are put in. These guarantee that the
appliances run correctly in rated working conditions.
The devices which monitor safety of the unit are the following:
High pressure safety valve (only for EWMIM COOLING ONLY-
EWMIMH HEAT PUMP 138÷262)
High pressure switch (PA)
Low pressure transducer (triggers low pressure alarm, see
Electronic Control Manual coupled to the unit)
Differential water pressure switch
Pressure switch
Intervention
high pressure
water differential
High pressure safety valve
(only for EWMIM
138÷262)
II.10.4 OPERATION OF COMPONENTS
II.10.4.1 Compressor functioning
The Scroll inverter compressors and the fixed Scroll compressors (only
262) are equipped with internal thermal protection.
Once the inner circuit breaker has tripped, normal operation is
automatically resumed when the windings temperature drops below the
pre-set safety value (this can take from a few minutes to several hours).
All fixed compressors are equipped with a thermal magnetic circuit
breaker with auxiliary contact signaling signal connected to the
electronic board (thermal protection alarm contact for 262).
IOM_EWMIM-EWMIMH_120a262_207984_200601_ES-EN-FR-DE-IT
START
t
Ask all unauthorised personnel to leave the area.
t
Is the water differential pressure switch activated
€
correctly?
t
YES
Is the working pressure reading correct?
t
YES
If you take the pressure on the high pressure side to
approx. 8 bar, are there gas leaks of >3
grams/year?
t NO
Does the unit display feature any alarms?
t NO
Start-up procedure completed!
Reset
42 Bar
33 Bar - Manual
80 mbar
105 mbar - Automatic
43 Bar
-
YES
€
€
€
€
II.10.4.2 Operation of work probes, antifreeze,
discharge and pressure
The water temperature probes (work probes and antifreeze) are
inserted inside a well in contact with the conductive paste and blocked
on the outside with silicone.
One is placed at the entrance of the heat exchanger and measures
the temperature of the return water from the system;
the other one is placed at the evaporator outlet and acts as work and
antifreeze probe.
Always check that both wires are firmly welded to the connector and
that this is properly inserted in the housing on the electronic board (see
wiring diagram provided). In order to check the efficiency of the probe,
use a precision thermometer immersed with the probe in a container full
of water at a certain temperature, after having removed the probe from
the socket paying attention to not damage it in the process. Pay
attention when repositioning the probe, by applying conducting paste in
the socket, placing the probe and applying silicon on the external parts
so to block it. In the event the antifreeze alarm triggers, reset the alarm
from the control panel; the unit starts only when the water temperature
exceeds the intervention differential.
The exhaust temperature probes are inserted inside a special sump
welded externally to the delivery pipe of both compressors.
These probes signal to the electronic board abnormal increases in the
exhaust temperature, generating a thermal protection alarm.
Pressure probes (transducers) are installed:
on the branch of high pressure
it measures the high pressure by generating its alarms and activating
and activating its protections. Adjust the summer operation
condensation control.
on the low pressure branch
it measures the low pressure generating the relative alarms and the
relative protections. They manage the behavior of the electronic
expansion valve, generate the low pressure alarm and regulate the
evaporation control in winter operation.
79
€
NO
Check and/or replace the
component. Contact an authorized
HITECSA Service Center.
Stop the unit and check the cause of
€
NO
this anomaly. Contact an authorized
HITECSA Service Center.
Stop the unit and check the cause of
the leak (according to EN 378-2).
€
YES
Contact an authorized
HITECSA Service Center.
Check the cause of the alarm.
€
YES
See the alarm table. Contact an
authorized HITECSA Service
Center.
ADVANCE