Hydrocarbon Refrigerants applied to Refrigerated Display Cabinets

Transcription

1 Hydrocarbon Refrigerants applied to Refrigerated Display Cabinets Ian Garvey Technical Director Carter Retail Equipment SIRAC Presentation 22 nd April 1

2 Objectives To design a close coupled remote display case (integral) Utilising a hydrocarbon refrigerant Giving the following Benefits Reliability Containment Energy saving System integration client specific 2

3 The Process Design Standards Refrigerant Selection Compressor Selection and Evaluation 3 rd Party Validation Production 3

4 Design Standards 4

5 Design Standards used EN EN IOR Guidelines on A2 & A3 Refrigerants ACRIB Guidelines for use of Hydrocarbon Refrigerants Standards Considered DESEAR Dangerous Substances Explosive Atmospheres Regulations 2002 Directive provides for a classification of the places where explosive atmospheres may occur in terms of zones and determines which equipment and protective systems groups and categories should be used in each zone. Manufacture and Service SSOW s ATEX 95 & 137 ATmospheres EXplosibles Defines potentially Explosive Atmospheres. Equipment is only considered to be within the scope of the directive if it is intended to be used in a potentially explosive atmosphere 5

6 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END 6

7 Occupancy Category Supermarkets come under the category A as domestic / public places 7

8 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END 8

9 Maximum Charge According to Occupancy category System requirements are <1.5kg per sealed system <5.0kg in special machinery rooms or in the open for indirect systems Due to our maximum refrigerant charge of 850g per sealed system our category is further subdivided to A2 9

10 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END 10

11 Condenser / Evaporator Airflow Calcs As our charge is >150g we have to carry out evap / cond airflow calculations, to ensure in the event of refrigerant loss there is no stratification good practice Note! As part of the design calculations it is given that only 1 system at any time may have a catastrophic failure 11

12 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END 12

13 Safe Electrics to Specification Electrics to IP67 or similar If not leak testing to be carried out in all areas of sources of ignition In accordance with To Ensure Value achieved shall never exceed 75% of LEL Value achieved shall not exceed 50% of LEL for a period exceeding 5 minutes 13

14 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END 14

15 The Design Compliance (simplified) Intended System Location Domestic Appliance Occupancy Category A Occupancy Category B Occupancy Category C Max Charge 150g Max Charge according table YES Charge Less than 150g NO Cond / Evap airflow to eqn Safe Electrics to spec Leak Testing NO YES END = Design in accordance to relevant standards 15

16 Refrigerant 16

17 Refrigerant Hydrocarbon Refrigerants Considered R290a circa 20% reduction in cooling capacity over R404a R1270 circa 10% increase in cooling capacity over R404a -source :- Hitachi provisional information Source:- BOC 17

18 R1270 Properties Source :- BOC 18

19 Compressor 19

20 Compressor Selection and Evaluation Client brief Integral case without loosing look and feel of remote cabinet Low profile Compressor Hitachi Horizontal Scroll Compressor ZS & DS range Application Use of R404a Compressor (ZS DS) range for use on HC Refrigerant Working with Hitachi Japan, Hawco Refrigeration UK Compressor construction All components compatible with HC refrigerants - bearings etc Testing Sign off Warranty given for use on HC s (CRE only) Long Term Testing HT Case running +3 years LT Case running circa 1 year 20

21 Compressor 21

22 Benefits of Design Capillary control No valves or special probes - Simple Critical charge No service ports No meddling! Factory sealed system Cleaner environment Better control measures Better evacuation levels Less Leaks Automated Pass/Fail 22

23 Existing Remote Case 23

24 Completed Design 24

25 Engineering 25

26 Range of Cases Available 26

27 3 rd Party Validation 27

28 Independent Verification of 3 rd Party Validation System design, compliant to standards Leak testing and reporting carried out to Standards Technical assistance were required Coolconcerns Used them for HC retrofit programme in 2006 Client nominated for all supply of equipment Understand our products and processes Technical assistance were required 28

29 Production 29

30 Production 2009 Initial Two Store Development - manual process SSOW required 3 metre exclusion zone Dedicated qualified/trained operatives Helium leak detection Manual charging Manual testing Time consuming 2010 Production Plan - Automated Minimum exclusion zone Helium leak detection Automated Evacuation leak test and charge Automated testing 30

31 Manual Process Production Layout Drawing Pressure test Manual Charge Manual Charge Test 4 Finish Case 31

32 Automated Process Production Layout Drawing Evac /lleak Test Charge Test Finish 32