Daikin EWAD900BJYNN/A [325/346] Water flow and pressure drop precautions

ESIE07-04 Pre-Test Run Checks

Part 4 – Commissioning and Test Run 4–13

1.10 Water Flow and Pressure Drop Precautions

Evaporator water

flow and pressure

drop

Balance the chilled water flow through the evaporator. The flow rates must fall between the minimum

and maximum values. Flow rates below the minimum values shown will result in laminar flow that will

reduce efficiency, cause erratic operation of the electronic expansion valve and could cause low

temperature cut-out. On the other hand flow rates exceeding the maximum values shown can cause

erosion, vibration and may cause the break on the evaporator water connections and tubes. Measure

the chilled water pressure drop through the evaporator at field installed pressure taps. It is important

not to include valve or strainer pressure drop in these readings.

Variable chilled water flow through the evaporator while the compressors are operating is not

recommended. Set points are based upon a constant flow and variable temperature.

Heat recovery

condenser water

flow and pressure

drop

Heat recovery condensers are supplied without the headers connection on both water side, entering

and leaving.

These Headers must be provided by the installer locally , including the wells pockets for

microprocessor control sensors.

Balance the hot water flow through the heat recovery condenser. The flow rates must fall between the

minimum and maximum values. Flow rates below the minimum values shown will result in laminar flow

that will reduce efficiency, cause erratic operation of the unit and could cause high pressure cut-out.

On the other hand flow rates exceeding the maximum values shown can cause erosion on the

condenser water connections and tubes.

Measure the hot water pressure drop through the condenser at field installed pressure taps. It is

important not to include header, valve or strainer pressure drop in these readings. Variable hot water

flow through the condenser while the compressors are operating is not recommended. Set points are

based upon a constant flow and variable temperature.

Leaving Connections

Entering Connections