Trane LIFT 81-P - Shut-Down; Flow Rate Calibration

6 | Commissioning
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6.3 Shut-down
6.3.1 Temporary shut-down
Disable the machine according to that described in the relative
command section.
Do not disconnect the power supply by acting on the
disconnecting switch on board the machine or the main switch
of the system. If no voltage is present, the crankcase heaters and
any anti-freeze heaters cannot work, thereby, posing a risk of
freezing.
6.3.2 Shut-down for long periods
Not using the unit for a long period of time requires the following
operations to be performed:
Disable the unit in any mode of operation it may be, from the control
panel.
Set the remote switch to "OFF" (if present) after having turned off the
unit.
Disable the internal terminal units by setting the switch of each unit
to "off".
Set the main switch of the system to ''off''.
Close the water valves.
If, during the period of inactivity the temperature drops below
zero, the system must be fully empties or topped up with
antifreeze liquid.
6.4 Flow rate calibration
Once the pump has started, verify that the fluid flow rate of the
utilities is within the expected values for the unit.
To verify:
Use pressure gauges set before and after the circulating pump to
measure the pressure difference.
Verify that the pressure difference measured is equal to the pressure
drop in the system, including the heat exchanger.
To correct:
Turn the valve installed downstream of the pump to increase or
decrease the pressure difference.
Mark the position of each valve to reposition it in the same position
after closing for maintenance operations.
If there are no pressure gauges:
Verify the temperature difference between the utility fluid input and
output when the unit is operating regularly (all compressors on).
The difference in water temperature between input and output must
be between 4° and 6°C:
-
If it is below 4°C, the water flow rate is too high: slightly
close the discharge valve of the pump.
-
If it is more than 6°C, verify the pressure drops in the water
circuit.
For units equipped with two pumps, you will have to repeat the
calibration for each pump.