BN-HGDTB June Replaces BN-HGDTB, March Mohave. Technical Guide

Transcription

1 BN-HGDTB June 2017 Replaces BN-HGDTB, March 2011 Mohave Technical Guide

2 Table of Contents Overview... 2 System Features... 3 Condensing Unit Mohave Hot Gas Defrost Quick Reference... 5 AWEF Ratings...11 Mohave Hot Gas Unit Cooler Typical Factory Piping. 19 Medium Profile Evaporator Large Unit Cooler Refrigeration and Defrost Operation Mohave Hot Gas Defrost Cycle Diagrams Overview The Mohave advanced hot gas defrost refrigeration system with controller utilizes hot gas to greatly reduce defrost times and operates in all outdoor ambient temperatures.* This leads to increased energy efficiency and product integrity in a refrigeration system that can be used in a greater variety of environmental conditions. This system utilizes a state-of-the-art electronic defrost controller with a proprietary control scheme that allows the system to continually operate at its most optimal level. This system can be applied for a minimum room temperature of -25F and with one or two evaporators. *Tested to -20 F ambient. Hot Gas Control Board Features & Benefits The Mohave controller completely manages timing and sequence of defrost Point to point wiring to all control components Automatically compensates for changes in outdoor temperatures Quick and easy troubleshooting Monitors all pressures, temperatures, and setpoints in real time. Easily programmable through a menu driven interface The control board with conformal coating will handle the toughest conditions LED indicators on the board clearly show system status Remote alarm notification Significant energy savings over electric defrost systems 2

3 Main System Features Condensing Unit Integral condenser sub-cooling circuit in condenser for added capacity and vapor free liquid Floating Tube condenser coil design Electronic defrost controller Pressure or ambient fan cycling for head pressure control Electronic pressure regulator for defrost control Anti-short cycling protection High pressure and low pressure controls Oil pressure safety control Easily accessible control box High efficiency Copeland Discus compressors with poe oil Thermally protected permanently lubricated ball bearing condenser fan motor(s) Receivers are sized for sufficient pumpdown capacity with inlet and outlet service valves Cabinet is constructed from painted galvanized steel Replaceable core liquid line filter drier Replaceable core suction filter Evaporators All components are factory installed and wired Independent or single point power supply from condensing unit 4 and 6 FPI medium and large unit coolers Features:. Mounted TXV and distributor nozzle. Mounted check valves. Mounted liquid line solenoid. Mounted suction P trap. Electric drain pan heater standard (mounted hot gas drain loop optional). Mounted and wired control contactors. System Match-ups available using ProSelect Electric Vs. Hot Gas Drain Pan Electric Drain Pan Heater (Std) In this option, the drain pan surface is heated with low wattage electric heater(s) The electrical power requirements to the evaporator are unchanged Hot Gas Drain Pan Loop In this option, hot refrigerant gas passes through a loop of copper tubing that heats the drain pan surface before it defrosts the evaporator coil Advantages Lower cost solution Defrost is even quicker because more hot gas is available to defrost the evaporator coil Advantages In applications where there is limited evaporator accessibility (ex: controlled atmosphere rooms) 3

4 Vertical Air Discharge Condensing Unit The BDV Outdoor Discus Condensing Unit features a leak resistant design which includes: The Floating Tube condenser coil design. Refrigerant carrying copper tubes do not contact any metal support sheets; instead, the coil is constructed with expanded anchor tubes which support the coil construction and do not carry refrigerant. The coil design eliminates one of the major causes of leaks in refrigeration systems Limited five year warranty against condenser tube sheet and center support leaks Designed for use with R-404A, R-507, R-407A, R-407F, R-407C, and R-448A/R-449A Polyol Ester Oil charge on all units Pre-bent copper tubes minimize braze joints on internal piping Encapsulated high pressure switch eliminates capillary tubes Sentronic oil safety control ServiceMate diagnostic module Electronic defrost controller Other Standard Features High efficiency Copeland Discus compressors Thermally protected, permanently lubricated ball bearing condenser fan motors Electrical controls including compressor contactor, relays, and electronic controls are located in easily accessible control box with a hinged cover Receivers sized for sufficient pump down capacity with inlet and outlet service valves Cabinet constructed from pre-painted steel Convenient access panels for easy servicing to internal components Suction and discharge vibration eliminators Separate subcooling circuit in condenser for added capacity and vapor free liquid Replaceable core liquid line filter drier and sight glass Replaceable core suction filter Anti-short cycle timer Suction accumulator Condenser fan cycling (pressure or temperature) Pressure relief valve on receiver Crankcase heater Optional Features Oil separator Fused disconnect switch Non-fused disconnect switch Coated condenser coils for protection against metal erosion in harsh environments Manual reset high pressure switch Low ambient kit with insulated, heated receiver Phase loss protection Adjustable head pressure control valves Demand Cooling Evaporator control contactors mounted in condensing unit Auxiliary temperature sensor for room temperature control Nomenclature BDV L 6 C BDV Vertical Air Discharge Nominal Horsepower HP HP HP HP HP HP HP HP HP HP HP HP HP Hot Gas Defrost 2 Refrigerant 6 R-404A, R-507, R-407A, R-407C, R-407F, R-448A/R-449A Application (SST) L Low (0 F to -40 F) M Medium (30 F to -10 F) Electrical Characteristics C /3/60 D 460/3/60 K 230/3/60 E 575/3/60 4

5 The Mohave Controller Fast, dependable, and efficient positive defrost of evaporators Five to ten minute defrost times in most applications Program Review Enter Monitor Reset Time Will operate efficiently in all outdoor ambient conditions* Significant energy savings over electric defrost systems Highest levels of product integrity through more stable box temperatures *Tested to -20 F ambient. Mohave Hot Gas Defrost Controller Quick Reference Guide Control Buttons Program Review: Review or Change the Program Settings Enter: Accepts changes into memory Clear/ Test Selection Knob Force Service Force Defrost Monitor: View Current Operating Conditions of the System Reset Time: Resets the time clocks of the microprocessor to 0 Clear/Test: Clear ignores program selections prior to pressing Enter and terminates Service Mode. Test causes the system to cycle through all of the outputs for troubleshooting Select Knob: Used for Cycling through Monitoring and Programming Parameters Force Service: Press this button twice to cause the system to pump down and remain off until the Clear button is pressed Force Defrost: System will pump down and begin a defrost cycle. This will not affect the normally scheduled defrosts Service Switch This toggle switch may be placed in the on position to force the system into Service Mode. The compressor will pump down and shut off. The evaporator fans will de-energize. The system can be left in service mode for seasonal OFF situations. Operating Modes Mode OFF COOL PMPD SERV DELY Description Compressor Off Compressor On in Cooling Normal Cooling Operation System in Pump Down Mode Service Mode, System is Off Timed Delay DEF1 Defrost Stage 1 Pre-Defrost or Bypass Mode DEF2 Defrost Stage 2 Defrost Mode DEF3 Defrost Stage 3 Post Defrost Equalization or Drain Down Mode FREZ TEST SERV EVAC Refreeze Mode Test Mode Service Mode Evacuation Mode 5

6 Electrical Box Features Condenser Fan Contactors Compressor Contactor Control Circuit Transformers Control Circuit Fuses & Service Switch All Service Controls are located in a separate electrical panel allowing field adjustments without disconnecting power to the unit Oil Pressure Switch ServiceMate Diagnostic Module Mohave Hot Gas System Controller Electrical Service Knockouts Main Power Block Typical Internal Piping Replaceable Core Liquid Filter Drier Pre-bent Internal Piping Prevents Braze Joints Defrost Solenoid Replaceable Core Suction Filter Bypass Solenoid Suction Stop Solenoid Easily Accessible Discus Compressor Electronic Pressure Regulator Galvanized Steel Base with Rigging Points 3-Way Valve Liquid Receiver with Service Valves Allow Charge Isolation Suction Accumulator 6

7 Performance Data Model BDV Medium Temperature R-404A or R-507 Model BDV 0752M6 0762M6 0802M6 1002M6 1202M6 1502M6 2002M6 2502M6 3002M6 3502M6 4002M6 Ambient Temp. F 25 F Saturated Suction Temperature F 20 F 15 F 10 F 5 F 90 70,900 64,300 57,900 51,700 45, ,600 61,300 55,300 49,400 43, ,500 58,500 52,800 47,100 41, ,300 53,000 47,700 42,400 37, ,300 73,400 66,600 60,000 53, ,800 70,100 63,500 57,300 51, ,100 66,800 60,700 54,600 48, ,200 60,600 54,900 49,200 43, ,300 86,000 77,900 70,200 62, ,500 82,600 74,900 67,500 60, ,800 79,200 71,800 64,400 57, ,000 72,400 65,700 59,000 52, , ,900 95,100 85,800 76, , ,600 91,300 82,200 73, ,300 96,200 87,400 78,600 70, ,700 87,500 79,300 71,200 63, , , , ,800 92, , , ,300 99,400 88, , , ,400 95,000 84, , ,400 95,700 86,200 76, , , , , , , , , ,200 98, , , , ,300 94, , , ,100 95,600 85, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,600 7

8 Performance Data Model BDV Medium Temperature 8 R-407A/R-407F Model BDV 0752M6 0762M6 0802M6 1002M6 1202M6 1502M6 2002M6 2502M6 3002M6 3502M6 4002M6 Ambient Temp. F 25 F Saturated Suction Temperature F 20 F 15 F 10 F 5 F 90 69,400 62,400 56,100 50,200 44, ,700 60,000 53,900 48,200 43, ,900 57,500 51,700 46,200 41, ,400 52,500 47,200 42,200 37, ,300 69,400 62,000 55,100 48, ,200 66,600 59,500 52,900 46, ,000 63,700 56,900 50,600 44, ,800 58,100 51,800 46,100 40, ,500 83,500 74,200 65,500 57, ,600 80,000 71,100 62,700 55, ,600 76,500 67,900 59,900 52, ,800 69,500 61,600 54,200 47, , ,900 91,400 80,900 71, ,700 98,900 87,800 77,600 68, ,100 94,700 84,100 74,300 65, ,800 86,400 76,600 67,500 59, , , ,200 92,900 81, , , ,900 89,000 78, , ,700 96,500 85,100 74, ,400 98,700 87,500 77,100 67, , , , ,900 96, , , , ,700 92, , , , ,500 88, , , ,200 92,100 80, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,300

9 Performance Data Model BDV Medium Temperature R-407C Model BDV 0752M6 0762M6 0802M6 1002M6 1202M6 1502M6 2002M6 2502M6 3002M6 3502M6 4002M6 Ambient Temp. F 25 F Saturated Suction Temperature F 20 F 15 F 90 61,900 54,800 48, ,700 52,900 46, ,600 51,000 45, ,500 47,400 41, ,600 61,700 54, ,100 59,500 52, ,800 57,300 50, ,100 53,100 46, ,200 75,400 67, ,400 72,800 64, ,500 70,100 62, ,500 64,500 57, ,800 92,100 82, ,500 89,100 79, ,200 86,100 76, ,100 79,500 70, , ,300 94, , ,700 91, ,900 99,000 88, ,300 91,000 80, , , , , , , , , , , ,800 94, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,700 9

10 Performance Data Model BDV Medium Temperature 10 R-448A/R-449A Model BDV 0752M6 0762M6 0802M6 1002M6 1202M6 1502M6 2002M6 2502M6 3002M6 3502M6 4002M6 Ambient Temp. F 25 F Saturated Suction Temperature F 20 F 15 F 10 F 5 F 90 67,500 60,600 54,300 48,400 43, ,100 58,500 52,400 46,700 41, ,700 56,300 50,400 45,000 39, ,700 51,900 46,400 41,400 36, ,600 67,800 60,600 53,800 47, ,800 65,300 58,300 51,800 45, ,000 62,700 56,000 49,700 44, ,200 57,500 51,300 45,600 40, ,700 82,300 73,600 65,300 57, ,200 79,300 70,700 62,800 55, ,700 76,100 67,800 60,100 52, ,600 69,600 61,900 54,600 47, , ,800 90,100 80,100 70, ,300 97,200 86,800 77,100 68, ,300 93,600 83,500 74,100 65, ,900 85,900 76,500 67,600 59, , , ,900 92,100 81, , , ,000 88,600 78, , ,700 96,000 85,000 74, ,200 98,600 87,700 77,300 67, , , , ,300 94, , , , ,500 91, , , ,400 99,700 87, , , ,900 91,900 80, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,500

11 AWEF Values: Medium/High Temperature Condensing Units - Cooler Application Model Outdoor R404A/R507A R407A/R407F R407C R448A/R449A BDV0752M BDV0762M BDV0802M BDV1002M BDV1202M BDV1502M BDV2002M BDV2502M BDV3002M BDV3502M BDV4002M These refrigeration systems are designed and certified for use in walk-in cooler applications. 11

12 Performance Data Model BDV Low Temperature R-404A or R-507 Model BDV 0602L6 Ambient Temp. F 0 F -10 F Saturated Suction Temperature F -15 F -20 F -30 F -40 F 90 55,500 44,800 39,800 35,100 26,900 20, ,000 42,700 37,900 33,400 25,400 19, ,500 40,600 36,000 31,600 23,900 17, ,400 36,500 32,200 28,200 20,900 14, ,200 52,000 46,300 40,900 31,400 23, L ,300 49,700 44,100 38,900 29,700 22, ,400 47,300 42,000 37,000 28,000 20, ,600 42,600 37,700 33,100 24,600 17, ,600 63,600 56,600 50,000 38,400 29, L ,200 60,800 54,000 47,700 36,300 27, ,900 58,000 51,400 45,300 34,300 25, ,100 52,400 46,300 40,500 30,300 21, ,000 70,400 62,700 55,700 43,000 32, L ,300 67,100 59,800 53,000 40,700 30, ,700 64,000 57,000 50,300 38,300 28, ,600 57,800 51,300 45,000 33,700 24, ,100 73,000 64,900 57,400 43,900 32, L ,900 69,400 61,800 54,500 41,300 30, ,800 66,000 58,800 51,700 38,700 27, ,400 59,300 52,600 46,100 33,600 22, ,500 96,600 86,700 77,300 60,000 45, L ,100 92,100 82,500 73,400 56,700 42, ,800 87,600 78,300 69,600 53,500 39, ,900 78,500 70,100 61,900 47,100 34, , , ,700 92,400 71,500 52, L , ,500 98,300 87,400 67,100 49, , ,500 92,800 82,400 62,800 45, ,500 91,500 81,900 72,400 54,200 37, , , , ,700 87,400 65, L , , , ,900 82,300 60, , , , ,200 77,300 56, , , ,300 90,700 67,200 47, , , , ,000 97,000 74, L , , , ,700 90,800 68, , , , ,200 84,900 62, , , ,300 98,500 73,400 51,800 12

13 Performance Data Model BDV Low Temperature Demand Cooling is required for all applications R-407A/R-407F Model BDV 0602L6 Ambient Temp. F 0 F -10 F Saturated Suction Temperature F -15 F -20 F -30 F -40 F 90 52,800 40,300 34,900 30,000 21,500 14, ,500 38,400 33,200 28,400 20,100 13, ,300 36,500 31,500 26,800 18,800 12, ,700 32,700 28,000 23,600 16,000 9, ,200 48,300 42,300 36,800 26,900 17, L ,700 46,100 40,300 34,800 25,200 16, ,100 43,900 38,200 32,900 23,400 14, ,100 39,600 34,100 29,000 19,900 12, ,200 58,500 50,700 43,600 31,300 20, L ,900 55,700 48,200 41,300 29,300 18, ,600 53,000 45,700 39,000 27,200 17, ,800 47,400 40,500 34,200 23,100 13, ,700 63,600 55,200 47,500 34,100 22, L ,000 60,500 52,400 45,000 31,900 20, ,400 57,500 49,600 42,400 29,600 18, ,900 51,400 44,000 37,200 25,100 14, ,700 73,500 64,100 55,200 39,000 25, L ,300 70,000 60,900 52,200 36,500 24, ,000 66,300 57,500 49,200 33,900 21, ,700 58,600 50,500 42,600 28,400 16, ,100 88,700 77,800 67,600 49,100 33, L ,200 84,700 74,200 64,400 46,500 31, ,300 80,700 70,600 61,100 43,900 29, ,500 72,600 63,300 54,400 38,300 24, , ,700 95,200 82,100 60,400 45, L , ,600 90,600 78,000 57,300 43, ,400 99,400 85,900 73,800 54,100 41, ,400 88,700 76,200 65,000 47,500 36, , , ,300 97,000 69,200 44, L , , ,000 92,000 66,200 40, , , ,400 86,900 60,400 36, , ,300 89,500 75,700 51,600 27, , , , ,900 83,700 51, L , , , ,700 78,200 46, , , , ,300 72,500 43, , , ,800 90,500 61,600 32,100 13

14 Performance Data Model BDV Low Temperature Demand Cooling is required for all applications R-448A/R-449A Model BDV Ambient Temp. F 0 F -10 F Saturated Suction Temperature F -15 F -20 F -30 F -40 F 90 51,600 39,300 34,000 29,300 21,400 15, L ,600 37,600 32,400 27,800 20,100 14, ,600 35,900 30,900 26,300 18,900 13, ,300 32,300 27,500 23,300 16,200 10, ,900 47,100 41,300 35,900 26,600 18, L ,600 45,100 39,300 34,100 25,000 17, ,300 43,100 37,400 32,300 23,300 15, ,700 39,000 33,500 28,600 19,900 12, ,800 57,300 49,700 42,900 31,200 21, L ,800 54,800 47,400 40,700 29,300 19, ,800 52,200 45,000 38,500 27,300 17, ,500 46,900 40,100 33,900 23,100 13, ,200 62,300 54,100 46,700 34,000 23, L ,900 59,600 51,600 44,300 31,800 21, ,500 56,700 48,900 41,800 29,600 19, ,700 50,900 43,500 36,800 25,100 14, ,100 71,900 62,700 54,000 38,700 26, L ,100 68,700 59,700 51,200 36,300 24, ,900 65,200 56,500 48,300 33,700 22, ,400 58,100 49,900 42,100 28,400 17, ,600 86,400 75,700 65,800 48,600 35, L ,200 82,800 72,400 62,800 46,200 33, ,700 79,100 69,100 59,800 43,600 31, ,600 71,500 62,200 53,500 38,300 26, , ,300 92,900 80,800 59,100 37, L , ,700 88,600 76,800 55,500 35, ,100 97,100 84,300 72,600 51,700 32, ,000 87,600 75,500 64,300 44,200 25, , , ,500 94,600 68,600 46, L , , ,600 90,000 64,400 42, , ,900 99,400 85,200 60,000 38, , ,000 88,300 74,500 49,300 33, , , , ,400 82,700 55, L , , , ,600 77,500 50, , , , ,500 72,000 45, , , ,600 89,200 59,900 39,100 14

15 Specifications and Dimensions Model BDV Model BDV Compressor Condenser Fan Data Connections No. Fans Dia. Liquid Suction Receiver (90% Full) R404A Lbs. Dim. Info. See Figure Approx. Net Weight Lbs. 0752M6 2DL3R78KE /8 1-3/8 93 / 81 A 1, M6 2DA3R89KE /8 1-3/8 93 / 81 A 1, M6 3DA3R10ME /8 1-5/8 93 / 81 A 1, M6 3DB3R12ME /8 1-5/8 93 / 81 B 1, M6 3DF3R15ME /8 2-1/8 93 / 81 B 1, M6 3DS3R17ME /8 2-1/8 142 / 123 C 1, M6 4DBNR20ME /8 2-1/8 142 / 123 C 1, M6 4DHNR22ME /8 2-1/8 142 / 123 D 1, M6 4DJNR28ME /8 2-1/8 216 / 188 D 1, M6 6DHNR35ME /8 2-1/8 216 / 188 D 2, M6 6DJNR40ME /8 2-1/8 216 / 188 E 3, L6 3DA3F28KE /8 1-3/8 81 A 1, L6 3DB3F33KE /8 1-3/8 81 A 1, L6 3DF3F40KE /8 1-5/8 81 A 1, L6 3DS3F46KE /8 1-5/8 81 A 1, L6 4DBNF54KE /8 1-5/8 81 A 1, L6 4DHNF63KE /8 2-1/8 81 B 1, L6 4DJNF76KE /8 2-1/8 81 C 2, L6 6DHNF93KE /8 2-1/8 123 C 2, L6 6DJNF11ME /8 2-1/8 123 C 2,200 15

16 Dimensions (Inches) Model BDV A 55.5 O 1.38 X 1.75K.O FRAME C/L O 2.50 K.O O LIQUID SUCTION LIQUID SUCTION B 55.5 O 1.38 X 1.75K.O FRAME C/L O 2.50K.O O LIQUID SUCTION LIQUID SUCTION C 55.5 O 1.38 X 1.75K.O FRAME C/L O 2.50K.O O LIQUID SUCTION LIQUID SUCTION D 55.5 O 1.38 X 1.75K.O FRAME C/L O 2.50 K.O O LIQUID SUCTION LIQUID E FRAME C/L O 2.50 K.O O 1.38 X 1.75K.O O LIQUID LIQUID LIQUID SUCTION

17 Electrical Data Model BDV Volts Model BDV Compressor Compressor Independent (STD) System Power Cond. RLA LRA No. Fans Fan FLA MCA MOP Evap Powered From Condensing Unit Evap Max Amps MCA MOP 0752M6 2DL3R78KE M6 2DA3R89KE M6 3DA3R10ME M6 3DB3R12ME M6 3DF3R15ME M6 3DS3R17ME M6 4DBNR20ME M6 4DHNR22ME M6 4DJNR28ME M6 6DHNR35ME M6 6DJNR40ME L6 3DA3F28KE L6 3DB3F33KE L6 3DF3F40KE L6 3DS3F46KE L6 4DBNF54KE L6 4DHNF63KE L6 4DJNF76KE L6 6DHNF93KE L6 6DJNF11ME *230/6/60 MCA = Minimum Circuit Ampacity MOP = Maximum Overcurrnent Protection Independent Vs. Single Power Supplies Independent Power Supplies for Condensing Units and Unit Coolers (Std) In this option, a separate high voltage power supply is run to each evaporator and the condensing unit Low voltage control wiring is run between the condensing unit and each evaporator (including evaporator sensor, liquid solenoid and evaporator control contactor(s) Single Power Supply for Condensing Unit Providing Power to Unit Coolers In this option, a power supply is run to the condensing unit and high voltage wiring is run from the condensing unit to power the fan motor and drain pan heaters in each evaporator Low voltage control wiring is run between the condensing unit and each evaporator for the evaporator sensor and liquid solenoid Advantages Electrician can run simple point-to-point power supplies without having to understand the control circuit wiring Evaporator disconnect switch wiring is simplified (if required) Refrigeration contractors can generally run the low voltage wiring with the refrigeration piping and make these wiring connections with a good understanding of the control circuit function The condensing unit wire size and fusing requirements are minimized because they don t include a worst-case remote evaporator load Lower cost installation solution Advantages A benefit for retrofit situations if there is existing control wiring that can be employed In applications where there is limited evaporator accessibility (ex: controlled atmosphere rooms) 17

18 Electrical Data Model BDV 460 Volts Model BDV Compressor Compressor Independent (STD) System Power Cond. RLA LRA No. Fans Fan FLA MCA MOP Evap Powered From Condensing Unit Evap Max Amps MCA MOP 0752M6 2DL3R78KE M6 2DA3R89KE M6 3DA3R10ME M6 3DB3R12ME M6 3DF3R15ME M6 3DS3R17ME M6 4DBNR20ME M6 4DHNR22ME M6 4DJNR28ME M6 6DHNR35ME M6 6DJNR40ME L6 3DA3F28KE L6 3DB3F33KE L6 3DF3F40KE L6 3DS3F46KE L6 4DBNF54KE L6 4DHNF63KE L6 4DJNF76KE L6 6DHNF93KE L6 6DJNF11ME MCA = Minimum Circuit Ampacity Independent Vs. Single Power Supplies MOP = Maximum Overcurrent Protection All selection require 3 phase power supply. Independent Power Supplies for Condensing Units and Unit Coolers (Std) In this option, a separate high voltage power supply is run to each evaporator and the condensing unit Low voltage control wiring is run between the condensing unit and each evaporator (including evaporator sensor, liquid solenoid and evaporator control contactor(s) Single Power Supply for Condensing Unit Providing Power to Unit Coolers 18 In this option, a power supply is run to the condensing unit and high voltage wiring is run from the condensing unit to power the fan motor and drain pan heaters in each evaporator Low voltage control wiring is run between the condensing unit and each evaporator for the evaporator sensor and liquid solenoid Advantages Electrician can run simple point-to-point power supplies without having to understand the control circuit wiring Evaporator disconnect switch wiring is simplified (if required) Refrigeration contractors can generally run the low voltage wiring with the refrigeration piping and make these wiring connections with a good understanding of the control circuit function The condensing unit wire size and fusing requirements are minimized because they don t include a worst-case remote evaporator load Lower cost installation solution Advantages A benefit for retrofit situations if there is existing control wiring that can be employed In applications where there is limited evaporator accessibility (ex: controlled atmosphere rooms)

19 Hot Gas Unit Cooler Typical Factory Piping Electrical Connections (this side) Note: Control contactors mount under a cover on front of unit (not shown) Air Flow Suction Connection Liquid Connection Liquid Solenoid Valve Thermostatic Expansion Valve Check Valves Check Valve Suction P-Trap Hot Gas Drain Pan Shown 19

20 Medium Profile Hot Gas Defrost Unit Coolers for use with the Bohn Mohave Hot Gas Defrost System Standard Features Mounted and wired control contactors Schrader valve provided for suction pressure measurement Permanent split capacitor (PSC), thermally protected, lifetime-lubricated motors in 115, and 460 volts All internal panels have been isolated which provides for quiet unit operation Motors plug into wiring harness for easier servicing Factory mounted liquid line solenoid valve, TXV, and distributor nozzle Electric drain pan heaters Four and six FPI coils Single point power supply Suction P trap Insulated drain pan on low temp systems Options UL approved totally enclosed motors EC motors (optional) available factory-installed or as a drop-in replacement through InterLink Commercial Refrigeration Parts in 115/1/60, /1/60 voltages Available in stainless steel cabinets and/or drain pan* Copper fin or coil coatings (Electrofin, and BohnGuard ) Mounted hot gas drain pan loop Evaporator control contactors mounted in condensing unit Insulated drain pan for medium temp systems * aluminum inner drain pan with insulated outer stainless steel drain pan E Solutions branded products and options are designed to exceed current energy and environmental standards. We have made a conscious commitment to developing environmentally innovative products that allow our customers to make energy efficient, eco-conscious choices. Products included in the E Solutions portfolio reduce costs, improve bottom lines, and enhance both equipment performance and service life. Choosing EC motors for this portion of the system decreases energy consumption and increases energy cost savings. Nomenclature BMG (6 FPI), BMF (4 FPI) BMG 190 B G A Vintage Code Hot Gas System Evaporator Capacity X 100 Voltage: A = 115/1/60 B = /1/60 M = 460/1/60 20

21 Medium Profile Unit Coolers Capacity and Electrical Data Hot Gas Defrost Model 10 F. TD -20 F. SST CFM No. Fan Data Motor Data (Total Amps) Electrical Supply Requirements Dia. (In.) * Air Throw (Ft.) Diffused (Std.) Models BMG/BMF 60 Hz. Extended (Opt.) HP 115/ 1/60 PSC Motor EC Motor 115V V 460V / 1/60 BMG (6 FPI MODELS) 460/ 1/60 115/ 1/ / 1/60 MCA MOP MCA MOP MCA MOP BMG ,000 4, / BMG ,000 7, / BMG ,000 6, / BMG ,000 8, / BMG ,000 8, / BMF (4 FPI MODELS) BMF ,000 4, / BMF ,000 7, / BMF ,000 6, / BMF ,000 9, / BMF ,000 8, / *Standard molded fan guards allow for extended air throw; optional wire guards promote air diffusion Air throw data based on 12-ft. high ceilings with no obstructions where velocity drops to 50 FPM Data appropriate for electric and hot gas defrost drain pan MCA = Minimum Circuit Ampacity MOP = Maximum Overcurrent Protection Physical Data Model No. of Fans Hot Gas Defrost Physical Data FPI MLG6 (6 FPI Models) Connections (Inches) Approximate Liquid Suction Net Weight (lbs.) BMG /2 1-3/8 ODF 216 BMG /2 1-3/8 ODF 242 BMG /2 1-3/8 ODF 269 BMG /2 1-5/8 ODF 312 BMG /2 1-5/8 ODF 345 MLG4 (4 FPI Models) BMF /2 1-3/8 ODF 214 BMF /2 1-3/8 ODF 239 BMF /2 1-3/8 ODF 266 BMF /2 1-5/8 ODF 307 BMF /2 1-5/8 ODF

22 Medium Profile Unit Coolers Dimensional Data 18-7/8" 480 mm 17-1/2" 444 mm 24" 608 mm Air Flow 23-1/4" 590 mm 2-1/2" 64 mm 15-1/2" 390 mm 22-3/4" 578 mm Refrigerant Connection End Electrical Connection End 6 FPI Models Hot Gas BMG *Factory piping extends behind the unit cooler and may add up to 6 inches to this dimension. 4 FPI Models Hot Gas BMF Dimensions A B C D E F in. mm in. mm in. mm in. mm in. mm in. mm BMG260 BMF /16 1, /4 1, / BMG310 BMF /16 2, /4 2, / BMG390 BMF /16 2, /4 2, / BMG430 BMF /16 3, /4 2, , /4 1, / BMG520 BMF /16 3, /4 2, , /4 1, / NOTE: Evaporator mounting brackets accept up to 1/2" hanger rod 22

23 Large Hot Gas Defrost Unit Coolers for use with the Bohn Mohave Hot Gas Defrost System Standard Features Mill finish aluminum provides an attractive design and structurally sound cabinet Thermo-Flex (with five-year limited warranty) is innovative, eliminates leaks, and reduces risk of refrigerant loss 850 RPM motors are quiet and reliable Liquid line solenoid wiring harness for faster installation Suction Schrader fitting for easier suction temperature measurement Captive fasteners on access panels for easy servicing Long air throw is ideal for large warehouse and industrial applications Electric drain pan heater Insulated drain pan heater for low temp systems Optional Features High CFM motor and fan combinations ( /3/60 and 460/3/60) Totally enclosed motors ( /3/60 and 460/3/60) Long air throw collars for large warehouse and industrial applications More factory mounted features for easier field installation (Consult factory) Evaporator control contactors mounted in condensing unit Insulated drain pan for medium temperature systems Mounted hot gas drain pan loop Nomenclature BHG (6 FPI), F (4 FPI) BHG 850 B P G A Vintage Capacity x 100 (standard motor/fan blade) Optional Motor Code T = Totally Enclosed Motors V = High CFM Option P = 3 Phase Motor Voltage Code A = 115/1/60 B = /1/60 C = /3/60 D = 460/3/60 M = 460/1/60 Hot Gas System Evap. 23

24 Large Unit Coolers Hot Gas Defrost Capacity & Electrical Data - 60Hz. Hot Gas Defrost Model 10 F. TD -20 F. SST Std. CFM No. Fan Data Dia. (In.) Air Throw (Ft.) Data appropriate for electric and hot gas defrost drain pan Note: TD = Temperature Difference = (Room temperature - saturated suction temperature) MCA = Minimum Circuit Ampacity MOP = Maximum Overcurrent Protection Std. with Collar HP /1/60 Wired 1 Phase Wired 3 Phase 6 FPI MODELS Standard Motor Data /3/60 Total Amps 460/1/60 Wired 1 Phase Electrical Supply Requirements V 460V Wired 3 Phase 460/3/60 MCA MOPD MCA MOP BHG ,000 9, / BHG ,000 9, / BHG ,000 12, / BHG ,000 12, / BHG ,000 16, / BHG ,000 16, / BHG ,000 20, BHG ,000 20, BHG ,000 24, / BHG ,000 26, / BHG ,000 35, / FPI MODELS BHF ,000 9, / BHF ,000 9, / BHF ,000 13, / BHF ,000 13, / BHF ,000 17, / BHF ,000 17, / BHF ,000 21, BHF ,000 21, BHF ,000 25, / BHF ,000 27, / BHF ,000 36, / Capacity Correction Factors for Electric and Hot Gas Defrost Units Saturated Suction Temperature F Saturated Suction Temperature C Multiply Capacity By

25 Large Unit Coolers Hot Gas Defrost High CFM Capacity & Electrical Data - 60Hz. Hot Gas Defrost Model 10 F. TD -20 F. SST Std. CFM No. Fan Data Dia. (In.) Air Throw (Ft.) Std. Standard Motor Data Electrical Supply Requirements Total Amps V 460V with Collar HP /3/60 460/3/60 MCA MOP MCA MOP 6 FPI MODELS BHG 450*V 49,500 11, BHG 550*V 60,500 11, BHG 640*V 70,400 15, BHG 740*V 81,400 15, BHG 810*V 89,100 21, BHG 950*V 104,000 21, BHG 1020*V 107,100 23, BHG 1200*V 126,000 23, BHG 1390*V 146,000 27, BHG 1650*V 174,000 29, BHG 2120*V 223,000 39, FPI MODELS BHF 400*V 42,000 12, BHF 480*V 50,400 12, BHF 560*V 58,800 17, BHF 650*V 68,300 17, BHF 710*V 74,600 22, BHF 840*V 88,200 22, BHF 890*V 91,200 23, BHF 1050*V 107,600 23, BHF 1220*V 125,000 32, BHF 1440*V 147,000 30, BHF 1860*V 190,000 40, Data appropriate for electric and hot gas defrost drain pan. Note: TD = Temperature Difference = (Room temperature - saturated suction temperature) MCA = Minimum Circuit Ampacity MOP = Maximum Overcurrent Protection High CFM models can handle external static pressure up to 1/2 of water High CFM models are designed for operation below +15 F S.S.T. CFM is at 0.0 external static pressure Capacity Correction Factors for Electric and Hot Gas Defrost Units Saturated Suction Temperature F Saturated Suction Temperature C Multiply Capacity By

26 Large Unit Coolers Physical Specifications - Hot Gas Defrost Hot Gas Defrost Model Size No. of Fans Connections (Inches) Liquid Suction Drain 6 FPI MODELS Approx. Net Weight (Lbs.) BHG /8 OD 1-5/8 OD 1-1/4 FPT 320 BHG /8 OD 1-5/8 OD 1-1/4 FPT 350 BHG /8 OD 2-1/8 OD 1-1/4 FPT 458 BHG /8 OD 2-1/8 OD 1-1/4 FPT 498 BHG /8 OD 2-1/8 OD 1-1/4 FPT 597 BHG /8 OD 2-1/8 OD 1-1/4 FPT 647 BHG 1, /8 OD 2-1/8 OD 1-1/4 FPT 842 BHG 1, /8 OD 2-1/8 OD 1-1/4 FPT 904 BHG 1, /8 OD 2-1/8 OD 1-1/4 FPT 958 BHG 1, /8 OD 2-5/8 OD 1-1/4 FPT 1,291 BHG 2, /8 OD 2-5/8 OD 1-1/4 FPT 1,781 4 FPI MODELS BHG /8 OD 1-5/8 OD 1-1/4 FPT 317 BHG /8 OD 1-5/8 OD 1-1/4 FPT 346 BHG /8 OD 2-1/8 OD 1-1/4 FPT 453 BHG /8 OD 2-1/8 OD 1-1/4 FPT 493 BHG /8 OD 2-1/8 OD 1-1/4 FPT 590 BHG /8 OD 2-1/8 OD 1-1/4 FPT 640 BHG /8 OD 2-1/8 OD 1-1/4 FPT 833 BHG 1, /8 OD 2-1/8 OD 1-1/4 FPT 894 BHG 1, /8 OD 2-1/8 OD 1-1/4 FPT 947 BHG 1, /8 OD 2-5/8 OD 1-1/4 FPT 1,276 BHG 1, /8 OD 2-5/8 OD 1-1/4 FPT 1,761 26

27 Large Unit Coolers Dimensions Figure C A B 8 G F /2* Refrigerant Piping End Accepts 1 2 Hanger Rod Electrical End *Factory piping extends behind the unit cooler and may add up to 6 inches to this dimension Hot Gas Defrost Models Dimensions (Inches) 6 FPI 4 FPI Figure A B C F G BHG 450 BHF / /8-37-3/ /32 BHG 550 BHF / /8-37-3/ /32 BHG 640 BHF / / / / /32 BHG 740 BHF / / / / /32 BHG 810 BHF / /4 60-1/8 37-3/ /32 BHG 950 BHF / /4 60-1/8 37-3/ /32 27

28 Large Unit Coolers Dimensions Figure C D E A B G F * Refrigerant Piping End Accepts 5 8 Hanger Rod Electrical End *Factory piping extends behind the unit cooler and may add up to 6 inches to this dimension Hot Gas Defrost Models Dimensions (Inches) 6 FPI 4 FPI Fig. A B C D E F G BHG 1,020 BHF / / / / /2 50-5/16 BHG 1,200 BHF 1, / / / / /2 50-5/16 BHG 1,390 BHF 1, / / / / / /16 BHG 1,650 BHF 1, / / / / / / / / / / / /2 50-5/16 BHG 2,120 BHF 1, / / / / / / /4 Air Throw Hot Gas Defrost Models 6 FPI 4 FPI Standard Motor RPM Standard HP Each Air Throw Air Throw with Collar Optional High CFM Motor RPM Optional HP Each Air Throw / , ,020-1, , & 1-1/ , ,650-2,120 1,440-1,860 1, / , Three Phase Motors are 1,140 RPM Air throw data based on 30 ft. ceiling height with no obstructions where velocity drops to 50 FPM Air Throw with Collar 28

29 REFRIGERATION OPERATION The refrigeration operation of the hot gas system is very similar to a standard refrigeration system. An external thermostat is connected to the hot gas control board at the terminal block connections labeled T-Stat and C (for common). When the normally open contact inside the thermostat closes (a call for cooling), the hot gas control board responds by activating a series of solenoids and contactors (described below) in order to initiate and maintain a refrigeration cycle. Later, when the thermostat contact opens, the hot gas control board deactivates the solenoids in a preset manner in order to safely turn off the refrigeration process and maintain an Off condition. At initial power up, the system defaults to the OFF mode for a minimum of two minutes. Following the two-minute hold off period, the control circuit examines the state of the thermostat input. If the thermostat input signal is activated (closed between T- Stat and C), the system begins the refrigeration startup process. Full refrigeration mode (or COOL mode) is achieved when the control board has activated the solenoids necessary to provide refrigerant flow between the evaporator(s) and the condensing unit (Suction Solenoid and Liquid Line Solenoid), activated the compressor contactor, deployed the appropriate control over the condenser fans, and turned on the evaporator fans. Refrigerant Solenoid and Compressor Contactor Control: The Suction Solenoid is initially activated following the power-up two-minute hold off time. It is maintained in the ON state until a defrost cycle is initiated. The timing of the liquid line solenoid (LLS) activation is based upon the saturated suction temperature (SST) which is calculated from the suction pressure value. If the SST is greater than 15ºF, the compressor contactor is activated before the LLS is activated in order to decrease the suction pressure prior to startup. When the SST drops to -5ºF, the LLS is activated. If the SST does not fall to -5ºF within 2 minutes, Er12 is activated and the system goes to OFF mode. If the SST is 15ºF or less, the LLS is activated immediately. When the SST rises to -10ºF for medium temperature applications or -20ºF for low temperature applications, the compressor contactor is activated. If the SST fails to rise in 2 minutes, ER11 is activated and the system goes to OFF mode. When the thermostat signal is deactivated, the liquid line solenoid is turned off immediately. The compressor contactor will stay activated until the suction pressure falls below the pre-programmed cut out pressure. The compressor contactor and all condenser fan contactors will be deactivated simultaneously. The evaporator fans will continue running. Condenser Fan Control: When the Condensing Unit Model is selected in the Program Review Menu; the program automatically activates the default Head Pressure Control Scheme. Method: Pressure Fan Cycling (PRES) All fans Minimum condensing temperature: 65F The default ON and OFF settings are optimized to maximize energy efficiency while still providing adequate pressure for the thermostatic expansion valve(s) to work properly. The parameters are refrigerant specific. Fans are staged to minimize fluctuations in head pressure during operation. During refrigeration operation, the hot gas controller monitors liquid pressure to determine if each fan should be ON or OFF. These settings and other fan control options may be modified by turning on the Expert Mode (XPRT) in the Program Menu. See Program Review and Optional Controls for more information. Evaporator Fan Control: After initial power-up, the evaporator fans will be turned off. When the system initiates the first cooling cycle, the hot gas controller monitors the temperature value of the evaporator defrost termination sensor mounted on the evaporator suction headers. When the controller determines that the suction header has reached the refreeze setpoint, the evaporator fans will be activated. If there are two evaporators, the fans will be energized by the first sensor to achieve setpoint. Once activated, the evaporator fans will continue to run until either a defrost cycle is initiated, or if the system is placed in SERVICE mode. Anti Short-Cycle Protection: During cooling mode, the control board is programmed to allow a minimum system ON time of 1 minute and a minimum OFF time of 2 minutes. 29

30 Pump Down At the end of each cooling cycle, when the box temperature is met, the hot gas control system will pump down and turn off the compressor. To pump down, the Liquid Line Solenoid(s) is deactivated and the compressor runs until the pressure measured at the suction accumulator falls below the pre-programmed cut out pressure value, or two minutes has elapsed. The compressor is then turned off until the start of the next cooling cycle. During the pump down process, the LED display will show PMPD. Manual Pump down: A single pole, single throw switch is connected to the Service SW input on the hot gas control board. Activating this switch (closing the contact) will cause the system to pump down and shut off. While in Service mode, the evaporator fans will turn off. Note that the system will not restart until the switch contact has been opened. The hot gas controller will display SERV while in Service mode. The system can also be pumped-down by pressing the SERVICE button twice. To restart the system, press the CLEAR button. 30

31 DEFROST OPERATION Defrost Timing/Schedule Programming The hot gas controller can be programmed with up to 12 defrost start times. The Program Review menu section describes the process to program or delete a valid start time. Note that clearing a start time by pressing CLEAR and the ENTER will disable all start times following the one being cleared. There must be 30 minutes of elapsed time following a start of defrost before another defrost can be scheduled. A defrost cycle can be initiated manually at any time. Force Defrost Manually To manually force the start of a defrost-cycle, press the FORCE DEFROST button. If the system is in COOL mode, the system will pump down and go to the off mode before the defrost process is started. Defrost Process The defrost process has four steps: Pre-defrost (DEF1) pressure equalization, Defrost operation (DEF2), Postdefrost (DEF3) pressure equalization and drain down, and Refreeze (FREZ). DEF1: Pre-defrost, or defrost step 1, always follows activation of Off mode. If the system is in Cool mode when the defrost cycle is activated, the control will pump down and go to Off mode before activating pre-defrost. The purpose of DEF1 is to equalize the refrigerant pressures between the condensing unit receiver and the evaporator(s). This is accomplished by first deactivating the evaporator fans, and the suction solenoid. Next the Bypass Solenoid and the evaporator Pan Heater contactor are activated. The time duration of the pressure equalization is programmed as EQUT in the PROGRAM REVIEW menu. DEF2: After the equalization time has elapsed, the Bypass Solenoid is deactivated. The Defrost Solenoid is activated 1 second later, followed by the 3-Way valve solenoid 1 second after that. Next, the pressure regulator control algorithm is enabled. The initial position is full open, but it quickly makes adjustments in order to stabilize the pressures and temperatures seen at the inlet of the suction accumulator. The compressor contactor turns on at the same time that the pressure regulator is activated. The ambient temperature is measured, and a determination is made of how many condenser fans should be operating. The correct number of condenser fans is activated at the same time as the compressor contactor. During the DEF2 operation, the pressure regulator continues to maintain the appropriate volume of refrigerant flow through the system based upon the current ambient conditions, the refrigerant type, and the type of cooling application. Termination of defrost is accomplished by either both evaporators reaching their target termination temps, or the liquid pressure measured between the receiver and the condenser coil reaching its target pressure, or the pre-programmed fail safe time. When one of the termination factors is realized, the compressor, condenser fan(s), and the defrost solenoid are turned off. The 3-Way valve and the Pan heaters are left on. The pressure regulator is activated to 100% open, and DEF3 begins. DEF3: Post-defrost has two purposes. The first is the transfer of high pressure refrigerant at the evaporator back to the condenser receiver by way of the pressure regulator. The pressure regulator is open 100% during this step. The second purpose is drain down time for the warm evaporators. This allows the water that was melted off of the coil to drain out of the evaporator drain pan. The time duration for this step is identical to the DEF1 equalization time. After the completion of the delay time period, the 3- way valve and the pan heater contactor are turned off. One second later the suction solenoid is turned on, and then one second after that the compressor turns on. The condenser fan control algorithm is also enabled. When the pressure measured at the suction sensor falls below 20 psig, the liquid line solenoid is activated and the process step changes to refreeze. 31

32 FREZ: The refreeze step is identical to cooling mode except that the evaporator fans are turned off. This is to allow the evaporator coils to freeze any remaining water that might be left over from the drain down step so that when the fans turn on, the water will not be sprayed into the refrigerated space. When the evaporator reaches the refreeze setpoint, the fans turn on and the system begins a cooling cycle. If the thermostat is satisfied, or deactivated, the system will run a cooling cycle for two minutes and then pump down and shut off. After the compressor is energized, the suction stop valve may be pulsed to limit the suction pressure at the compressor. Mohave Hot Gas Defrost Cycle Diagrams Black = Piping Inactive Gray = Piping Active 32

33 Mohave Hot Gas Defrost Cycle Diagrams Black = Piping Inactive Gray = Piping Active 33

34 Notes 34

35 Notes 35

36 For more information on Bohn refrigeration products, contact your sales representative or visit us at A Brand of Heatcraft Refrigeration Products, LLC 2,175 West Park Place Blvd. Stone Mountain, GA 30,087 (800) 537-7,775 Visit our website at for technical literature online. Since product improvement is a continuing effort, we reserve the right to make changes in specifications without notice. 36