Carrier 30KAV-ZE Series Installation, Operation And Maintenance Instructions page 78

12 - OPTIONS
NOTE:
■ In the case of frost protection of the unit by low air
temperature, the percentage brine must be evaluated
accordingly.
■ The maximum glycol content for units equipped with a
hydraulic module is 45 %.
■ The maximum recommended temperature differential
is 5 K.
■ To facilitate maintenance operations, it is recommended
that isolation valves are installed upstream and downstream
of the machine
It is essential to use precisely the correct concentration of glycol
in the loop. Too high a concentration may have significant adverse
effects on the performance of the evaporator, and therefore of the
unit as a whole (decrease in the evaporation temperature). Too
low a concentration may generate alarms or allow the evaporator
to freeze. Damage caused by frost is not covered by the warranty.
Evaporator minimal brine flow:
■ Option 5 (no turbulator): Minimal flow is the flow from Ecat
selection. Variable flow is not allowed. (A certain flow is
necessary to the evaporator to work.)
■ Option 6 (turbulator): Minimal flow is the same as for standard
unit (see chapter "application data"). For variable flow, it is
recommended to control pump on the Delta_T given on the
Ecat full load selection.
IMPORTANT: Option 6 - Turbulators - water flow direction
The water flow direction must be respected for the turbulators.
If there is a risk that the flow will be reversed, check valves must
be installed to guarantee the positioning of the turbulators.
As the unit operates at a pressure which is close to atmospheric
pressure, it is recommended that the moisture indicators on the
EXV are checked regularly.
Hydraulic kit and option 5:
If the hydraulic kit option is selected alongside option 5, the pumps
will be set at a default minimum frequency of between 35 Hz and
45 Hz, depending on the options, to prevent the flow rate being
too low. This minimum frequency may, however, be adjusted using
the control.
Brine + Heat recovery
When the Brine and heat recovery options are combined,
the glycol type and concentration must be entered in the software
(Service1 table).
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