The Air Vent Operation - Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook

[6-5 Hydro Unit Replacement Instructions ]
6-5-2

The air vent operation

This operation removes the air that remains after water is supplied to the water circuit.
Perform this operation after completion of water- and refrigerant-piping work, air tightness test, evacuation
of refrigerant circuits, and refrigerant charging (and debris removal, if performed).
1.Preparation for the air vent operation
1.Turn on the breaker, and then open the auto air vent valve (accessary) on the water piping and the air vent valves on
the indoor units.
Refer to the Installation Manual for the location of air vent valves.
(If there are air vent valves on the field-installed pipes, open the valves as well.)
Indoor unit (Example: PEFY-W-VMA-E)
2.Supply water from the suction pipe on the Hydro unit.
3.Check that water comes from each air vent valve, and perform the air vent operation.
2.Air vent operation
1.Set DIPSW 002-3 from OFF to ON.
2.Set DIPSW 002-1 from OFF to ON (If system checking is unnecessary, this step can be skipped).
3.The LED will indicate "Air0," "Air1," "Air2," "Co-1," "Co-2," "Co-3," and "AirE" in order over a period of up to maximum
minutes, and after maximum minutes have passed, the water pump will stop.
4.Set the dipswitch 002-1, 002-3 from ON to OFF
5.Close the all air vent valves and auto air vent valves.
6.Stop the water supply.
3.Checking for the presence of residual air
1.If there is residual air in the circuit, it will be noisy. Check for water leaks from the pipe, and then, perform the air vent
operation again.
Flowchart for air vent operation (Set DIPSW 002-3 to ON first, and then DIPSW 002-1 to ON.)
Intermittent operation of water pump (20 min)
Step 1
Operation of all indoor units (20 min)
Step 2
Operation of individual indoor unit
Step 3
(10 min per one connected indoor unit)
Heating operation of all indoor units (20 min)
Step 4
System check
Step 5
(18 min + 30 sec per one connected indoor unit)
( 1 ) The operation can be forced to stop by setting DIPSW 002-4 from OFF to ON.
( 2 ) If it is found during any step that air ventilation has not been completed to the desired degree, go back to Step 2-1.
( 3 ) If Error appears on the LED, turn off the breaker, turn it back on, and start over at step 2-1.
Be sure to perform this operation when changing the system configuration.
4.End processing
Set the dipswitches 002-1 and 002-3 to OFF after completion of air vent operation.
10 -
chapter 6
Install a non-return valve to prevent water in the water circuit
flooding back to the water supply pipe, or remove the water
supply hose after the air vent operation.
LED and DIPSW positions
.
The operation is performed while air is
discharged from the water pipe. [Air0]
The residual air will be roughly removed
by operating all indoor units. [Air1]
The residual air will be removed by operating
indoor units for each branch. [Air2]
The saturated air in the circulating water will be
removed by performing heating operation for all
indoor units and raising the temperature of the
circulating water. [Co-2]
The following system check will be performed.
• Water pressure checking [Co-1]
• Water piping length checking [Co-2, Co-3 to AirE]
BS_06_E