Heatcraft Refrigeration Products H-ENGM0408 manuale d’uso

Commer cial Refrigeration Cooling and F reezing L oad Calculations and Ref erence Guide H-ENGM0408, April 2008 (Replaces H-ENGM0806, August 2006 ) Engin eering Manual Head Pressure Control V a lve Oil Separ ato r Compressor Suc tion Accumul ato r Suc tion Filt er Ev aporat or Condense r Liquid Li ne Soleno id V alv e Liquid Li ne Sight Glass Receiv[...]

2 © 2008 Heatcraft Refrigeration Pr oducts LLC www.thecoldstandar d.com www.coldy oucancounton.com Commercial Refrigeration P ar ts ™ History of H igh P er formance , Innovation and Pr oduc t Selection Larkin has been the most trusted brand of refrigeration pr oduc ts for clean environments sinc e 1928. W ith its innovative pr oducts, it is uniq[...]

3 T ables 1. W all heat loads 13 2. Insulated block K factors 13 3. Allowance f or sun eect ............................................................................ 13 4. Aver age air changes per 24 hours for storage rooms above 32ºF . (0ºC.) due to door openings and inltration 14 5. Aver age air changes per 24 hours for storage rooms b[...]

4 Job Sur vey The person inv olved in a heat transfer calculation needs information in order to pr edict accurately the heat load on a refrigerated structure . The mor e complete the information, the better the calculation. Good calculations are the rst step in assuring adequate refrigeration equipment is selected f or the project. The initial j[...]

5 [ (4.88) ( door height) (area/2) (minutes open) ( temp . di . ºF .) (enthalpy incoming air – enthaply war ehouse air) ] [ (1–X)] Specic Volume of Incoming Air Where X = % of heat transmission blocked b y thermal barr ier . F or freezers it becomes necessary to provide heat in the base slab to avoid fr eezing of the ground water and hea[...]

6 6. Hourly Heat Load The hourly heat load serves as the guide in selecting equipment. It is found by dividing the nal BTU/24 hour load by the desired condensing unit run time . 35ºF . rooms with no timer 16 hr . 35ºF . rooms with timer 18 hr . Blast coolers/F reezers with positive defrost 18 hr . Storage F reezers 18-20 hr . 25ºF . - 34ºF .[...]

7 Re frige ra tion Load Esti mat e Form (fo r ro oms a b ov e 32ºF) Bulle ti n Ab ov e32-05 Basis f or Estima te Room Di mensi ons: Widt h ft. x Length f t. x Hei ght ft. V ol ume: (L) x (W) x (H) = cu. f t. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t o b e r ed uced fro[...]

8 Re frige ra tion Load Esti mat e Form (fo r ro oms a b ov e 32ºF) Bulle ti n Ab ov e32-05 Basis f or Estima te Room Di mensi ons: Widt h f t. x Lengt h f t. x Hei ght f t. V ol ume: (L) x (W) x (H) = cu. f t. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t o b e r ed uced [...]

9 Re frige ra tion Load Esti mat e Form (fo r ro oms a b ov e 32ºF) Bulle ti n Ab ov e32-05 Basis f or Estima te Room Di mensi ons: Widt h f t. x Lengt h f t. x Height ft. V ol ume: (L) x (W) x (H) = cu. f t. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t o b e r ed uced fr[...]

10 Re frige ra tion Load Esti mat e Form (fo r ro oms b e low 32ºF) Bul let in Be low32-05 Estima te fo r: Basis f or Estima te Room Di mensi ons: Widt h f t. x Lengt h f t. x Hei ght f t. V ol ume: (L) x (W) x (H) = cu. f t. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp. ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t [...]

11 Re frige ra tion Load Esti mat e Form (fo r ro oms b e low 32ºF) Bul let in Be low32-05 Estima te fo r: Basis f or Estima te Room Di mensi ons: Widt h f t. x Lengt h f t. x Hei ght f t. V ol ume: (L) x (W) x (H) = cu. f t. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp. ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t [...]

12 Re frige ra tion Load Esti mat e Form (fo r ro oms b e low 32ºF) Bul let in Be low32-05 Estima te fo r: Basis f or Estima te Room Di mensi ons: Widt h f t. x Lengt h f t. x Height f t. V ol ume: (L) x (W) x (H) = cu. ft. Ambie nt T emp ºF . (Corr ec ted fo r su n load) — Room T emp. ºF . = ºF . T .D. Pro d uc t Load (a) lb s./da y o f t o [...]

13 Insulation Insul. K F actor 6” 8” 10” 12” Air 4.65 6.94 6.65 6.50 6.40 V ermiculite .47 2.73 2.67 2.64 2.62 Sawdust .45 2.70 2.65 2.62 2.60 Cork .38 2.62 2.57 2.55 2.53 Rock Wool .30 2.52 2.49 2.47 2.45 Mac. P aper .28 2.50 2.46 2.45 2.43 Styrofoam .24 2.45 2.42 2.40 2.40 P olyurethane .16 2.36 2.33 2.33 2.32 T ype of East S outh W est F[...]

14 T able 4 Av erage air changes per 24 hours for storage rooms above 32ºF . (0ºC.) due to door openings and inltration. Air Air Air Volume Changes Volume Changes V olume Changes Cu. Ft. Per 24hrs. Cu. Ft. P er 24hrs. Cu. Ft. Per 24hrs. 200 44.0 2,000 12.0 25,000 3.0 250 38.0 3,000 9.5 30,000 2.7 300 34.5 4,000 8.2 40,000 2.3 400 29.5 5,000 7.[...]

15 Specic Specic Latent Product Storage Conditions Highest Heat Heat Heat Loading Storage Relative Approximate Freezing Above Below of Density Commodity T emp. Humidity Storage Point Freezing Freezing Fusion Approx. (Alphabetical Listing) ºF . % Life* ºF . BTU/lb./F BTU/lb./F BTU/lb . lb./Cu . Ft. T able 7 Storage requir ements and properti[...]

16 Specic Specic Latent Product Storage Conditions Highest Heat Heat Heat Loading Storage Relative Approximate Freezing Above Below of Density Commodity T emp. Humidity Storage Point Freezing Freezing Fusion Approx. (Alphabetical Listing) ºF . % Life* ºF . BTU/lb./ºF BTU/lb ./ºF BTU/lb. lb/Cu. Ft. T able 7 Continued Maple Sugar 75 - 80 60[...]

17 F R U I T S VEGET ABLES MISCELLANEOUS T able 8 Heat of Respiration (Appr ox.) BTU / LB. / 24 Hrs. Storage T emperature Degree F . P roduct 32ºF . 40ºF . 60ºF . ºF . Other Apples 0.25 - 0.45 0.55 - 0.80 1.50 - 3.40 Apricots 0.55 - 0.63 0.70 - 1.00 2.33 - 3.74 Avocados — — 6.60 - 15.35 Bananas — — 2.30 - 2.75 @ 68º 4.2 – 4.6 Blackbe[...]

18 T able 9 Heat Loads of Keg and Bottled Beer (BTU / 24 HR) T ype and Size T emperature Reduction of Beer only. ºF . of Container 60 50 40 30 20 15 10 5 Wood One Keg — — 12000 9000 6000 4500 3000 1500 Half Keg — — 5600 4650 3100 2325 1550 775 Quar ter Keg — — 3200 2400 1600 1200 800 400 Eighth Keg — — 1640 1230 820 615 410 205 Alu[...]

19 Banana Ripening Room Banana hands or cluster shipped greens in berboard cartons, 10” x 16” x 22” , holding 42 lb. net (47 lbs. gross w eight) with 864 boxes (3,288) lbs , net in a carload lot. T emperature held 56 to 58ºF . Ripening facility consists of 5 or more air tight rooms to permit a completely weekly turn-over (1/2 carload room[...]

20 Design Design Ground Dr y Bulb Wet Bulb T emp. State City ºF . ºC. ºF . ºC. ºF . ºC. Alabama Birmingham 95 35 78 26 70 21 Mobile 95 35 80 27 75 24 Alaska F airbanks 82 28 64 18 40 4 Arizona Phoenix 105 41 76 24 80 27 Tucson 105 41 72 22 80 27 Y uma 110 43 78 26 80 27 Arkansas Little Rock 95 35 78 26 70 21 California Bakerseld 105 41 70 [...]

21 Refrigeration Equipment Selection General When the hourly BTU load has been determined, equipment can now be selected based on the information obtained in the initial job survey. Some of the factors aecting equipment selection are: 1. Equipment Balanc e 2. T emperature Di erence ( T .D.) 3. Capacity Con trol/Product Safety 4. Type of Opera[...]

22 Holding freezer 40 80 Packaged Holding center 40 80 Cutting Room 20 30 M eat Chill Room 80 120 Boxed Banana Ripening 120 200 Vegetables and F ruit Storage 30 60 Blast Freezer 150 300 Work Areas 20 30 Unpack aged Meat Storage 30 60 Recommended Number of Air Changes T ype of Application Minimum Maximum -1,000 31.02 15.27 .0778 1.04 1.03 1.005 -500[...]

23 Application T .D. C oil Notes Conv enience Store 10 - 15ºF . Low Silhouett e Multiple units for adequate air co verage Up to 18’ long = 1 coil Up to 30’ long = 2 coils Up to 40’ long = 3 coils Estimating guide: Cooler 100 SF/ton* Freezer 75 SF/ton* Holding Warehouse 10 - 15ºF . Medium or Forklift Operation Heavy Duty Aver age air changes[...]

24 Baffle Glass Display Door Unit Cooler Recommended C oil Replacement Left Large cooler or freez er Right Large cooler or freez er Large cooler or freez er where one wall will not accommodate all r equired evaporators or where air-thro w distance must be considered. Note: Always a void placement of unit coolers directly above doors and door openin[...]

25 Line Sizing The f ollowing T ables 22 through 24A on pages 25 through 30 indicate liquid lines and suction lines for all condensing units for R-22, R-404A, R-134a, and R-507. When determining the refrigerant line length, be sur e to add an allowance f or ttings. See T able 26 on page 31. T otal equivalent length of refrigerant lines is the su[...]

26 T able 22A. Recommended Line Sizes for R-134a (continued) * SUC T ION LI NE S IZ E LI QUI D L INE SI ZE S UC TI ON TEM PE RA TU RE Receiver to +10˚F 0˚F Expansion V alve SYSTEM Equivalent Lengths Equivalent Lengths Equivalent Lengths C AP ACITY 25' 50' 75' 100' 150' 200' 25' 50' 75' 100' 150&ap[...]

27 T able 23. Recommended Line Sizes for R-22 * SUC TION LINE SIZE SUCTION TEMPERA TURE SYSTEM +40˚F +20˚F +10˚F 0˚F CAP ACITY Equivalent Lengths Equivalent Lengths Equivalent Lengths Equivalent BTU/H 25' 50' 75' 100' 150' 200' 25' 50' 75' 100' 150' 200' 25' 50' 75' 100&[...]

28 T able 23A. Recommended Line Sizes for R-22 (continued) * S UC TI ON L IN E SI ZE L IQU ID L IN E SI ZE S UC TI ON TEM PE RA TU RE Receiver to 0˚F -10˚F -20˚F Expansion V alve SYSTEM Lengths Equivalent Lengths Equivalent Lengths Equivalent Lengths CAP ACITY 100' 150' 200' 25' 50' 75' 100' 150' 200'[...]

29 T able 24. Recommended Line Sizes for R-404A and R-507 * SUC TION LINE SIZE SUC TION TEMPERA TURE SYSTEM +20˚F +10˚F -10˚F -20˚F CAP ACITY Equivalent Lengths Equivalent Lengths Equivalent Lengths Equivalent BTU/H 25' 50' 75' 100' 150' 200' 25' 50' 75' 100' 150' 200' 25' 50&apos[...]

30 T able 24A. Recommended Line Sizes for R-404A and R-507 (continued) * SUC T ION LI NE S IZ E L IQ UID LI NE S IZ E SUC T ION TE MP ERATUR E Receiver to -20˚F -30˚F -40˚F Expansion V alve SYSTEM Lengths Equivalent Lengths Equivalent Lengths Equivalent Lengths CAP ACIT Y 100' 150' 200' 25' 50' 75' 100' 150&apo[...]

31 T able 26. Equivalent F eet of Pipe Due to V alve and F itting Friction Copper Tube , O.D ., Type “L ” 1/2 5/8 7/8 1 1/8 1 3/8 1 5/8 2 1/8 2 5/8 3 1/8 3 5/8 4 1/8 5 1/8 6 1/8 Globe V alve (Open) 14 16 22 28 36 42 57 69 83 99 118 138 168 Angle V alve (Open) 7 9 12 15 18 21 28 34 42 49 57 70 83 90˚ T urn Through T ee 3 4 5 6 8 9 12 14 17 20 2[...]

32 T able 27. Recommended Remote Condenser Line Sizes R-134a R-22 R507 & R-404A Liquid Line Liquid Line Liquid Line Net T otal Discharge Cond. to Discharge Cond. to Discharge Cond. to Evaporator Equiv. Line R eceiv er Line Receiver Line R eceiv er Capacity Length (O.D .) (O .D.) (O.D .) ( O.D .) (O .D.) (O .D.) 3,000 50 3/8 3/8 3/8 3/8 3/8 3/8 [...]

33 T able 28. W eight of Refr igerants in C opper Lines During Operation (Pounds per 100 lineal f eet of type "L " tubing). Line Size Suction Line at Suction T emperatur e O.D . Liquid Hot Gas in Inches Refrigerant Line Line -40˚F -20˚F 0˚F +20˚F +40˚F 134a 4.0 .15 .01 .01 .02 .04 .06 3/8 22 3.9 .22 .02 .03 .04 .06 .08 R507, 404A 3.4[...]

34 T able 29. F ahrenheit – Celsius T emperature Con version Chart The number in bold type -face in the c enter column refers to the temperature , either Celsius or F ahrenheit, which is to be converted to the other scale. If con verting Fahrenheit t o Celsius the equivalent temperatur e will be found in the left column. If converting Celsius to [...]

35 T able 30. Conv ersion F actors (constant) W ater 500 = 8.33 lbs./gal. x 60 min, – (Con ver ts GPM t o lbs./hr .) Air 4.5 = 60 min 13.35 Cu. Ft./lb . – (C onverts CFM to lbs./hr .) 1.08 = 4.5 x 0.241 BTU/lb./ºF . – (lbs./hr . x Sp. Ht. of Air) 0.68 = 4.5 x 1054.3 BTU/lb. 7000 gr/lb. – (4.5 combined with heat of vaporization of water at [...]

36 T able 32. English Conv ersion F actors & Data T able 33. English to Metric Conv ersion F actors T o Convert Measurements F rom T o Multiply By Cubic F eet Cubic Inches 1728 Cubic Inches Cubic Feet 0.00058 Cubic F eet G allons 7.48 Gallons Cubic F eet 0.1337 Cubic Inches G allons 0.00433 Gallons Cubic Inches 231 Barrels Gallons 42 Gallons Ba[...]

37 78.1 SR/lb dry air 7000 Use of the P sychr ometric Char t Fr om two k nown pr oper ties of air , its condition can be located on the Psy chrometric char t and all remaining pr oper ties can then be found by r eading the appropriate scale. Figur e 1 Illustrates a condition plotted at the intersection of its dry bulb and wet bulb temperatures. The[...]

38 Appendix — Charts Low T emperature P sychrometric Chart (-40 to 50ºF .) Standard Atmospheric P ressure of 29.921 in HG Atmospheric Pressure at other altitude Altitude Pressure Ft. in HG -1000 31.02 -500 30.47 0 29.92 500 29.38 1000 28.86 2000 27.82 3000 26.83 4000 25.84 5000 24.90 6000 23.98 7000 23.09 8000 22.22 9000 21.39 10000 20.58 15000 [...]

39 Appendix — Charts Medium T emperature P sychrometric Chart (32 to 130ºF .) Standard Atmospheric P ressure of 29.921 in HG Courtesy of ASHRAE — Reproduced by permission.[...]

40 Glossar y of Refrigeration T erms 1. Accumulator - a shell placed in suction line for separating liquid refrigerant entrained in suction gas. 2. Air Changes - the amount of air leak age is sometimes computed by assuming a certain number of air changers per hour for each room, the number of changes assumed being dependent upon the type, use and l[...]

41 6x6x8 36 4750 6389 4488 6037 4583 6505 4929 7041 5274 7577 6x8x8 48 5417 7274 5119 6974 5225 7407 5630 8028 6034 8648 6x10x8 60 6055 8100 5722 7655 5806 8213 6265 8911 6725 9609 8x8x8 64 6188 8291 5848 7835 5934 8410 6405 9127 6876 9844 8x10x8 80 6954 9269 6572 8759 6631 9363 7165 10169 7699 10974 8x12x8 96 7669 10174 7247 9614 7273 10234 7867 1[...]

42 Tips f or Quick Selec tion Guide W alk- In Cooler Box L oad Parameter 1. 95ºF . ambient air temperature surrounding bo x. 2. 4” St yrene (R=16.7, K=0.24) w alls/ceilling, 6” concrete slab oor . 3. Average product load with 5ºF . pull down in 24 hours . 4. BTUH load based on 16-18 hour compressor run time for 35ºF . box (timer r ecommen[...]

43 Rapid Load Calculat or for Large C oolers and Fr eezers Design Conditions: 95ºF . ambient; hea vy service; 16-hr . compressor running time; average number of lights , motors, and people; product load gured according to accompan ying table; product trac calculated at 30 degr ee temperature reduction for coolers, 10 deg ree temperature r ed[...]

44 ® C L I M A T E C O N T R O L Commercial Refrigeration Parts ™ Since product improv ement is a continuing eort, we reserve the right to make changes in specications without notice. ® C L I M A T E C O N T R O L Commercial Refrigeration Parts The name behind the brands you trust. ™ Heatcraft Refrigeration P roducts LL C 2175 West P ar[...]