Centrifugal Water Chillers. Scott Meyerkord

Transcription

1 Centrifugal Water Chillers Scott Meyerkord Trane Account Manager

2 Chilled Water System

3 absorption centrifugal helical-rotary

4 Centrifugal Water Chillers

5 Centrifugal Water Chillers Components

6 components of a Centrifugal Water Chiller compressor motor condenser 6 evaporator control panel starter

7 Compressor

8 Impeller blades

9 Multistage Compressor

10 Multistage Compressor impellers inlet vanes

11 Centrifugal Compressor volute diffuser passage impeller passages

12 centrifugal compressor Energy Conversion velo ocity refrigerant enters diffuser static pre essure refrigerant enters impeller refrigerant fi enters volute path through compressor

13 Condenser refrigerant vapor baffle cooling tower water tube bundle liquid refrigerant

14 expansion device Orifice Plates orifice plates to evaporator H 1

15 expansion device Orifice Plates orifice plates to evaporator H 2

16 2-stage chiller Economizer refrigerant vapor to second stage of compression orifice liquid refrigerant from condenser liquid refrigerant to evaporator

17 3-stage chiller Economizer refrigerant vapor to third stage of compression refrigerant vapor to second stage of compression orifice liquid refrigerant from condenser orifice liquid refrigerant to evaporator

18 Evaporator tube bundle liquid refrigerant chilled water return liquid distributor ib t eliminator orifice system

19 Motor motor motor gear-drive impeller impellers direct-drive gears

20 Hermetic Motor Cooling stator tt rotor liquid refrigerant drain

21 Controls and Starter control panel starter

22 Centrifugal Water Chillers Refrigeration Cycle

23 2-stage centrifugal chiller Refrigeration Cycle 2-stage compressor economizer evaporator condenser expansion devices

24 Refrigerant Operating Pressures HCFC-22 HFC-134a pres ssure HCFC-123 atmospheric pressure temperature

25 Low-Pressure Chillers compressor suction elbow evaporator

26 Purge System

27 Centrifugal Water Chillers Maintenance Considerations

28 Maintenance Considerations Operating log Mechanical components Heat-transfer surfaces Fluid analysis

29 operating log ASHRAE Guideline 3 Chilled water inlet and outlet Oil pressures, temperature, temperatures and pressures and levels Chilled water flow Record refrigerant activity, Evaporator refrigerant temperature and pressures Motor voltage and amperage Evaporator approach Purge activity temperature Condenser water inlet and outlet temperatures and pressures Condenser water flow Condenser refrigerant temperature and pressures Condenser approach temperaturet

30 maintenance considerations Mechanical Components Recommended d Maintenance Hermetic Compressor and motor: no routine maintenance required. Compressor teardown / overhaul inspection every 8 to 10 years or 25,000 to 30,000 operating hours Temperature Controls: no routine maintenance calibration required Visually inspect overall unit Inspect safety controls and electrical components Service motor starters: t Tighten electrical l connections, service contractors, megger test motor, visual inspection of transition resistors. Pressurize and leak test annually or as indicated by the purge rate

31 maintenance considerations Mechanical Components Other design-specific requirements Remove oil sample for Lab Analysis: Change oil when oil analysis dictates Replace oil filter annually or as required Replace purge filter drier annually Visual Inspection of Condenser Tubes Annually Check operation of oil sump heater

32 maintenance considerations Heat Transfer Surfaces Recommended maintenance Use a qualified water treatment specialist Clean condenser tubes as needed, mechanical brush cleaning annually Clean water-side pump strainers Test tubes every 3 years

33 maintenance considerations Tube Analysis Eddy Current Testing Test evaporator tubes every 4-5 years Test condenser tubes every 2-3 years

34 Fluid Analysis Oil analysis Conduct annual analysis to verify system integrity

35 Oil Analysis Why perform regular oil analysis? Helps reduce maintenance costs Detects problems without compressor disassembly Extends service life of oil charge Reduces environmental problems related to oil disposal Helps maintain compressor efficiency and reliability

36 Oil Analysis Analytical l Data

37 Oil Analysis Written Recommendations

38 Oil Analysis Graphical Representation of Data