Hydro Unit Replacement Instructions; Debris Removal Operation - Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook

[6-5 Hydro Unit Replacement Instructions ]

6-5

Hydro Unit Replacement Instructions

6-5-1

Debris removal operation

This operation removes the debris that may have been introduced during installation from the water circuit.
Perform this operation after completion of water- and refrigerant-piping work, air tightness test, evacuation
of refrigerant circuits, refrigerant charging, and electrical work.
1.Preparation for debris removal 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.Set DIPSW 011-1 to ON. (→Opens the flow control valve and facilitates water flow)
3.Supply water from the suction pipe on the Hydro unit.
4.Check that water comes from each air vent valve, and set DIPSW 011-4 to OFF to perform the debris removal
operation.
2.Debris removal operation
1.If there are a large amount of debris in the water in the field-installed pipes, set DIPSW 002-1 from OFF to ON.
(Refer to the flowchart for debris removal operation for details.)
Perform the debris removal operation. (Each air vent valve should stay open.)
2.Forty minutes after the completion of debris removal operation, the LED will indicate "AirE." The LED indication will
change to "Air0," "Air1," and "AirE" in order. Then, the water pump will stop.
3.Stop the water supply, and check that no water is coming out of the air vent valves.
4.Open the water-vent valve.
Slowly open the strainer. (Note that if it is opened fast, water may blast out.)
Remove the strainer, clean its inside, and refit it.
5.Make sure the strainers are re-installed.
Flowchart for debris removal operation (DIPSW2-1 is ON.)
Intermittent operation of water pump (20 min)
Step 1
Operation of all indoor units (20 min)
Step 2
( 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 debris removal operation has not been completed to the desired degree, start over at
Step 2-1.
<General cautions>
(1) To avoid malfunction, do not connect or disconnect the power connector of the water pump being powered on.
(2) Check for water leaks from the field-installed pipe joint during operation.
(3) Do not pull the housing joint on the connection of the water pipe with pliers so that undue force is applied.
(4) If Error appears on the LED, turn off the breaker, turn it back on, and start over at step 2-1.
3.End processing
Set the dipswitche 002-1 to OFF after completion of debris removal operation.
BS_06_E
Install a non-return valve to prevent water in the water circuit
flowing 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]
Debris in the pipe will accumulate into the
strainer by operating all indoor units. [Air1 to AirE]
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