York YCAS0130 manual Commissioning, Inspection, Refrigerant Charge, Valves, Compressor Oil, Fans

Commissioning

FORM 201.19-NM1 (204)

COMMISSIONING

PREPARATION

Commissioning of this unit should only be carried out by YORK Autho- rized personnel.

The Millennium Microcomputer Control System Operating Instructions must be read in conjunction with this section.

PREPARATION – POWER OFF

The following checks should be made with the customer supply/supplies to the unit switched OFF.

Inspection

Inspect unit for installation damage. If damage is found take action and/or repair as appropriate.

Refrigerant Charge

Units are normally shipped as standard with a full refrigerant operating charge. Check that refrigerant pressure is present in both systems and that no leaks are apparent. If no pressure is present a leak test must be undertaken. The leak(s) should be located and repaired. Repaired systems and units supplied with a nitrogen holding charge must be evacuated with a suitable vac- uum pump/recovery unit as appropriate to below 100 microns.

Do not liquid charge with static water in the evaporator. Care must also be taken to liquid charge slowly to avoid excessive thermal stress at the charging point. Once the vacuum is broken, charge into the condenser coils with the full operating charge as given in the Technical Data Section.

Valves

Open each compressor suction, economizer, and dis- charge valve fully (counter-clockwise) then close one turn of the stem to ensure operating pressure is fed to the pressure transducers. Open the liquid line service valve fully and ensure the oil return line ball valve is open in each system.

Compressor Oil

To add oil to a circuit - connect a YORK hand oil pump (Part No. 470-10654-000) to the 1/4" oil charging valve on the oil separator piping with a length of clean hose

or copper line, but do not tighten the flare nut. Using clean oil of the correct type (“L” oil), pump oil until all air has been purged from the hose then tighten the nut. Stroke the oil pump to add oil to the oil system. The oil level should be between the middle of the lower and middle of the upper sight glasses of the oil separator. Approximately 5 gallons is present in the entire chiller system, with 1-2 gallons in the oil separator.

Fans

Check that all fans are free to rotate and are not dam- aged. Ensure blades are at the same height when rotated. Ensure fan guard is securely fixed.

Isolation/Protection

Verify that all sources of electrical supply to the unit are taken from a single point of isolation. Check that the maximum recommended fuse sizes given in the Technical Data Section have not been exceeded.

Control Panel

Check the panel to see that it is free of foreign materials (wire, metal chips, etc.) and clean out if required.

Power Connections

Check to assure the customer power cables are connected correctly. Ensure that connections of power cables within the panels to the circuit breakers, terminal blocks or switch disconnectors are tight.

Grounding

Verify that the unit’s protective terminal(s) are properly connected to a suitable grounding point. Ensure that all unit internal ground connections are tight.

Overloads

Ensure that the fan overloads settings are correct for the type of fan fitted.

Supply Voltage

Verify that the site voltage supply corresponds to the unit requirement and is within the limits given in the Technical Data Section.

Control Transformer

The 3-wire control transformer is mounted external to the panel. It is important to check that the correct primary tapping has been used:

With the supply voltage to the unit turned off, remove the lid to the transformer box.

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