Daikin Water Chiller WSC087-BAABC

Warning: This maintenance check requires trained personnel with PPE!

Enter the leaving water temperature

Enter the saturated refrigerant temperature

Calculate the approach temperature (subtract saturated refrigerant temperature from leaving water temperature)

Note: Daikin's high efficiency heat exchangers have very low design approach temperatures, in the order of one to one and one half degrees F.

Is the approach temperature within the normal range?

If not, excessive tube fouling could be present.

Enter the condenser pressure drop

Is the condenser pressure drop within the normal range?

Warning: This procedure requires trained personnel with PPE!

Enter the leaving water temperature

Enter the saturated refrigerant temperature

Calculate the approach temperature (subtract saturated refrigerant temperature from leaving water temperature)

Note: Daikin's high efficiency heat exchangers have very low design approach temperatures, in the order of one to one and one half degrees F.

Is the approach temperature within the normal range?

If not, excessive tube fouling could be present.

Enter the condenser pressure drop

Maintain a log of the operating conditions, and check that the unit has the proper oil and refrigerant charge.

Record the oil, suction, and discharge pressures

Record the condenser and chiller water temperatures

Record the suction line temperature at the compressor

Calculate the suction superheat by subtracting the saturated temperature equivalent of the suction pressure from the suction line temperature.

Note any extreme changes in subcooling and/or superheat over a period of time. These may indicate losses of refrigerant or possible deterioration or malfunction of the expansion valves.

Proper superheat setting is 0 to 1 degree F (0.5 degree C) at full load. Such a small temperature difference can be difficult to measure accurately.

Another method is to measure the compressor discharge superheat, the difference between the actual discharge temperature and the saturated discharge temperature.

Warning: Do not use oxygen or a mixture of R-22 and air to build up pressure as an explosion can occur causing serious personal injury.

Loss of the entire refrigerant charge?

Enter the pressure after charging refrigerant (psig)

Enter the pressure after adding dry nitrogen (psig)

Leak test with an electronic leak detector passed?

Water flow through the vessels maintained?

Any leaks found in welded or brazed joints?

If any leaks are found in welded or brazed joints, or it is necessary to replace a gasket, relieve the test pressure in the system before proceeding. Brazing is required for copper joints.

Is the chiller subject to freezing temperatures?

If yes, drain the condenser and chiller of all water.

Use dry air to force all water out of the condenser.

Blow out the tubes of the condenser and evaporator.

Circulate antifreeze through the water circuits to avoid freeze up.

Have measures been taken to prevent the shutoff valve in the water supply line from being accidentally turned on?

If a cooling tower is used, has the water pump been exposed to freezing temperatures?