Units With Hydronic Module And Fixed Speed Pump - Carrier 30RBM 160 Installation, Operation And Maintenance Instructions

9.2 - Units with hydronic module and fixed speed
pump
General information
See the paragraph on "Units without hydronic module"
Hydronic circuit cleaning procedure
• Open all control valves completely (item 22).
• Start up the unit's pump.
• Read the value of the flow on the user interface.
• Let the pump run for 2 hours continuously to clean up
the system's hydraulic circuit (presence of contaminating
solids).
• Perform another reading.
• Compare this value to the initial value.
• A reducing value of the flow indicates that the filters on
the system need to be removed and cleaned. In this case,
close the shut-off valves on the water inlet and outlet
(item 19) and remove the filters (items 20 and 1) after
draining the hydronic part of the unit (items 6).
• Remove the air from the circuit (items 5 and 17).
• Repeat until all fouling is removed from the filter
Water flow rate adjustment procedure
Once the circuit has been decontaminated, read the flow rate
on the user interface and compare the value obtained with the
theoretical selection value.
If the flow rate read is greater than the specified value, this
indicates that the overall pressure drop in the system is too low
compared to the available static pressure generated by the pump.
In this case, close the control valve (item 22) and read the new
flow rate value.
Repeat as necessary, closing the control valve (item 22) until
the system's specific pressure drop corresponding to the unit's
design flow rate is achieved.
NOTE:
If the network has an excessive pressure drop in relation to
the available static pressure delivered by the unit pump, the
nominal water flow rate cannot be obtained (lower resulting
flow rate) and the difference in temperature between the water
inlet and outlet of the water type heat exchanger will be
increased.
To reduce the system's hydronic network pressure drop:
• Reduce the pressure drops of individual components
(bends, level changes, options, etc.) as much as possible;
• Use the correct pipe diameter;
• Do not extend the hydronic systems
Example: Unit with specific nominal flow 10.6 l/s
Legend
1 Unit pump curve
2 Pressure drop in the hydronic kit (to be measured on the pressure gauge installed on the water
inlet and outlet)
3 Pressure drop in the system with wide open control valve
4 Pressure drop in the system after setting the valve to obtain the nominal flow specified.
Water flow rate, l/s
33