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19
English
anti-seizing pump
The 30AWH__H units are equipped with protection
against the seizing of the pump motor shaft. To allow this
function, do not empty the system or disconnect the power
during long periods of inactivity.
In any case, if the pump rotor shaft seizes after a long
period of inactivity, the user must do the following to
unblock it:
- Disconnect the power.
- Remove the front panel.
- Unscrew the shaft-protection plug on the back of the
pump.
- Insert a screwdriver in the slot and turn the rotor
shaft.
- Remount the protection plug.
- Reconnect the power.
System cleaning and water characteristics
In the case of a new installation, or cleaning the circuit, it
is necessary to perform a preventive cleaning of the
system.
In order to guarantee the good operation of the product,
each time you clean the system, replace the water or add
glycol, check that the liquid appears clear, without visible
impurities and that the hardness is less than 20 °f.
anti-freeze protection
If unit is switched off during the winter period when
outdoor air temperatures below 0°C can occur and
ethylene glycol is not used, it is recommended that the
entire system is drained through the drain unit valve, Fig 9,
item 3, and the system drain, Fig 12/13, item 5.
6 - WaTer connecTIonS (fIg. 14/15)
Make the plate heat exchanger hydraulic connections
with the necessary components, using material which will
guarantee that the screwed joints are leak-proof.
The figures 12 and 13 show a typical water circuit
installation.
For an application with a water circuit, the following
recommendations must be taken into account:
1. The external circulation pump must be installed in the
return water pipe work immediately before the heat
pump (unit without hydraulic module).
2. It is advisable to install shut-off valves to allow
isolation of the most important circuit components, as
well as the heat exchanger itself.
These valves (ball, globe or butterfly valves) should
produce a minimum pressure drop when they are
open.
3. Provide unit and system drains at the lowest system
point.
4. Install purges in the higher sections of the installation.
5. Pressure ports and pressure gauges should be installed
upstream and downstream of the external water
pump.
6. All piping must be adequately insulated and
supported.
Installation of the following components is obligatory:
1. The presence of particles in the water can lead to
obstructions in the heat exchanger.
It is therefore necessary to protect the heat exchanger
inlet with an extractable mesh filter. The filter mesh
gauge must be at least 10 mesh/cm
2
.
2. After assembling the system, or repairing the circuit,
the whole system must be thoroughly cleaned with
special attention paid to the state of the filters.
3. Pump flow rate control is made through a flow control
valve, which must be installed on the delivery pipe
during installation.
4. When water has to reach temperatures below 5°C, or
the equipment is installed in areas subject to
temperatures below 0°C, it is necessary to mix water
with inhibited ethylene glycol in suitable quantity.