09-02 CHILLERS WATER - PACKAGED CHILLER UNITS - For demonstration only - do not use!

Warning Chiller units may be operated remotely and it is essential that the equipment be isolated at source before commencing any maintenance work. These notes should be read in conjunction with the manufacturer's recommended maintenance procedures and in particular supplementary work may be required in the case of larger units above 50kW. Many packaged water chillers have microprocessor controls that can be interrogated using passwords. The password is usually at two levels, level one for interrogation and level two for alterations. For service work access to level one is required. These processors can be used for diagnostic purposes and coupled to pressure transducers can also give pressure readings.


ITEM FQ ACTION NOTES
1. Status. 3m Check operating status. Note: With computer room chilling units always check with computer staff before service or maintenance. Do not only rely on the microprocessor readouts, always check against calibrated equipment if in any doubt.
2. Refrigeration circuits 3m Check circuit pressures and superheat temperatures. Check alarm and run lights and remote alarm lights associated with packs. Refrigeration circuits should be alternated at least every three months by means of the 'lead/leg' selector switch. Where operating information is displayed on central console, check that no discrepancies exist between display and master gauges, if these do occur report and change transducer(s). For non electronic systems check installed gauges against master gauges.
3. Refrigerant 3m Check for refrigerant and all leaks. Refrigeration circuits should be alternated at least every three months by means of the 'lead/leg' selector switch. Where operating information is displayed on central console, check that no discrepancies exist between display and master gauges, if these do occur report and change transducer(s). For non electronic systems check installed gauges against master gauges.
4. Expansion valves 3m Adjust if necessary. Only by a competent technician.
5. Chilled water supply 3m Check supply and return water temperatures. If closed system check for presence of water.
6. Glycol 3m Check glycol concentration in chilled water. If concentration has fallen check pipework for leaks as per item 8.
7. Chiller water flow rate. 3m Check that this is in accordance with the manufacturer s recommended figure.  

Frequency 1W 1M 2M 3M 4M 6M 12M 18M 24M 36M 48M
Cumulative Timings 0 0 0 2.00 0 0 3.00 0 0 0 0

 

09-02 CHILLERS WATER - PACKAGED CHILLER UNITS
ITEM FQ ACTION NOTES
8.Leakage 3m Check all pumps and pipework for leaks and rectify. Do no overlook remote condensers and pay particular attention to bolted joints, sight glass stands and atmospheric relief valve vent.
9. Refrigerant pipework. 3m Inspect and check for vibration, chaffing security and leakage. Vibration is usually the result of loose or inadequate fixing of pipe supports and can give rise to leakage of refrigerant.
10. Standby circuits. 3m Check operation. Vibration is usually the result of loose or inadequate fixing of pipe supports and can give rise to leakage of refrigerant.
11.Flood alarm. 3m Check operation. If serving computer facilities, check that alarm is not connected to computer shut-down system.
12. Digital readouts. 3m Check operation. If serving computer facilities, check that alarm is not connected to computer shut-down system.
13. Controls. 3m Check operation of temperature control thermostats. Inspect electrical panel and components for wear especially the compressor contactor(s). Check operation of safety thermostats and timers. Calibration } Interrogation } Control adjustment }
14. Hours run meter. 3m Check and record.  

Frequency 1W 1M 2M 3M 4M 6M 12M 18M 24M 36M 48M
Cumulative Timings 0 0 0 2.00 0 0 3.00 0 0 0 0

 

09-02 CHILLERS WATER - PACKAGED CHILLER UNITS
ITEM FQ ACTION NOTES
15. Insulation. 3m Check condition and make good any defects. Poor or faulty insulation can lead to ice build up, loss of efficiency and energy wastage.
16. Electrical. 12m Check for damage to flexible conduits. Tighten all terminal connections. Isolate control panel and inspect for signs of overheating. Check integrity of electrical insulation. Include pump motors.(See also MOTORS)
17. Safety cut-outs. 12m Check all safety cut-outs including high and low pressure safety cut-outs and the antifreeze thermostat cut-out for operation and correct calibration. Individual machines vary, cut outs could include i. .oil differential switches, ii. .oil, high and low temperature, iii. .water temperature differential switches on chillers and evaporators.
18. Pump strainers. 12m Check condition. Check waterside pressure drop across the heat exchanger(s) for fouling. WORK ON REFRIGERANT SYSTEMS MAY ONLY BE CARRIED OUT BY A TECHNICIAN WHO HOLDS A CERTIFICATE FOR THE SAFE HANDLING OF REFRIGERANT AND WHO WORKS FOR A COMPANY REGISTERED WITH REFCOM.

Frequency 1W 1M 2M 3M 4M 6M 12M 18M 24M 36M 48M
Cumulative Timings 0 0 0 2.00 0 0 3.00 0 0 0 0