Heatcraft Refrigeration Products H-ENGM0806, H-ENGM0408 manual Glossary of Refrigeration Terms

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Glossary of Refrigeration Terms

1.Accumulator - a shell placed in suction line for separating liquid refrigerant entrained in suction gas.

2.Air Changes - the amount of air leakage 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 location of the room.

3.Air Cooler, Forced Circulation - a factory-made encased assembly of elements by which heat is transferred from air to evaporating refrigerant.

4.Ambient Air - generally speaking, the air surrounding an object. In a domestic or commercial refrigerating system having an air-cooled condenser, the temperature of the air entering the condenser.

5.Back Pressure - loose terminology for suction pressure of refrigeration vapor in a system.

6.British Thermal Unit (BTU) - heat required to produce a temperature rise of 1 degree Fahrenheit in 1 lb. of water. The mean BTU is 1/180 of the energy required to heat water from 32ºF. to 212ºF.

7.Change of Air - introduction of new, cleansed or recirculated air to conditioned space, measured by the number of complete changes per unit time.

8.Chill - to apply refrigeration moderately, as to meats, without freezing.

9.Chilling Room - room where animal carcasses are cooled after dressing prior to cold storage.

10.Comfort Air Conditioning - the simultaneous control of all, or at least the first three, of the following factors affecting the physical and chemical conditions of the atmosphere within a structure for the purpose of human comfort; temperature, humidity, motion, distribution, dust, bacteria, odors, toxic gasses and ionization, most of which affect in greater or lesser degree human health or comfort.

11.Comfort Cooling - refrigeration for comfort as opposed to refrigeration for storage or manufacture.

12.Defrosting Cycle - a refrigeration cycle which permits

cooling unit to defrost during off period.

13.Dehumidification - the conservation of water vapor from air by cooling below the dew point or removal of water vapor from air by chemical or physical methods.

14.Dehydration - the removal of water vapor from air by the use of absorbing materials. (2) The removal of water from stored goods.

15.Dew Point - temperature at which condensation starts if moist air is cooled at constant pressure with no loss or gain of moisture during the cooling process.

16.Differential (of a control) - the difference between cut-in and cut-out temperature or pressure.

17.Dry Bulb Temperature - temperature measured by ordinary thermometer (term used only to distinguish from wet-bulb temperature).

18.Duct - a conduit or tube used for conveying air or other gas.

19.Evaporator - the part of a system in which refrigerant liquid is vaporizing to produce refrigerant.

20.External Equalizer - in a thermostatic expansion valve, a tube connection from the chamber containing the evaporation pressure-actuated element of the valve to the outlet or the evaporator coil. A device to compensate

for excessive pressure drop throughout the coil.

21.Flash Gas - the gas resulting from the instantaneous evaporation

of refrigerant in a pressure-reducing device to cool the refrigerant to the evaporations temperature obtained at the reduces pressure.

22.Flooded System - system in which only part of the refrigerant passing over the heat transfer surface is evaporated, and the portion not evaporated is separated from the vapor and recirculated. In commercial systems, one controlled by a float valve.

23.Frost Back - the flooding of liquid from an evaporator into the suction line accompanied by frost formation in suction line in most cases.

24.Head Pressure - operating pressure measured in thedischarge line at the outlet from the compressor.

25.Heat Exchanger - apparatus in which heat is exchanged from one fluid to another through a partition.

26.Heat, Latent - heat characterized by change of state of the substance concerned, for a given pressure and always at a constant temperature for a pure substance, i.e., heat of vaporization or fusion.

27.High Side - parts of refrigerating system under condenser pressure.

28.Infiltration- air flowing inward as through a wall, leak, etc.

29.Liquid Line - the tube or pipe carrying the refrigerant liquid from the condenser or receiver of a refrigerating system to a pressure-reducing device.

30.Low Side - parts of a refrigerating system under evaporator pressure.

31.Pressure Drop - loss in pressure, as from one end of a refrigerant line to the other, due to friction, etc.

32.Refrigerating System - a combination of inter-connected refrigerant-containing parts in which a refrigerant is circulated for the purpose of extracting heat.

33.Respiration - production of CO2 and the heat by ripening of perishables in storage.

34.Return Air - air returned from conditioned or refrigerated space.

35.Sensible Heat - heat which is associated with a change in temperature; specific heat x change of temperature; in contrast to a heat interchange in which a change of state (latent heat) occurs.

36.Specific Heat - energy per unit of mass required to produce one degree rise in temperature, usually BTU per lb. degree F. numerically equal to cal. per gram degree C.

37.Standard Air - air weighing 0.075 lb. per cu. ft. which is closely air at 68ºF. dry bulb and 50% relative humidity at barometric pressure of 29.92 in. of mercury of approximately dry air at 70ºF. at the same pressure.

38.Suction line - the tube or pipe which carries the refrigerant vapor from the evaporator to the compressor inlet.

39.Superheat - temperature of vapor above its saturation temperature at that pressure.

40.Temperature, Wet-Bulb - equilibrium temperature of water evaporating into air when the latent heat of vaporization is supplied by the sensible heat of air.

41.Thermal Valve - a valve controlled by a thermally responsive element, for example, a thermostatic expansion valve which is usually responsive to suction or evaporator temperature.

42.Throw - the distance air will carry, measured along the axis of an air stream from the supply opening to the position, is the stream at which air motion reduces to 50 fpm.

43.Ton of Refrigeration - a rate of heat interchange of 12,000 BTU per hour; 200 BTU per min.

44.Unit Cooler - adapted from unit heater to cover any cooling element of condensed physical proportions and large surface generally equipped with fan.

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Contents Engineering Manual Table of Contents ForwardWall heat loads Insulated block K factors TablesOpenings and infiltration Job Survey Refrigeration Load CalculationsSafety Factor Air Change LoadProduct Load Daily figureTemperature above 32ºF 20-22 hr Hourly Heat LoadLoad Calculation Forms 50ºF. rooms and higher with coilExample 35ºF Convenience Store Cooler With Glass Doors Example 35ºF Beef Cooler Inches Type Ceiling Walls Floor Example -20ºF Ice Cream Hardening Freezer Example -10ºF Beef Freezer Gallons of ice cream @ Overrun Appendix Tables Wall Heat LoadsEffective K Factor in Block Thickness of Insulation Allowance for Sun EffectVolume For long storage multiply the above values byStorage Room 40ºF .4ºC 50ºF ºCStorage requirements and properties of perishable products Not based on maintaining nutritional valueMaple Sugar Heat of Respiration Approx BTU / LB. / 24 Hrs Storage Temperature Degree F ProductºF. Other Heat gain due to operation of battery operated lift truck BTU / 24 HRHeat equivalent of electric motors Heat equivalent of OccupancyBanana Ripening Room Banana Rooms Refrigeration RequirementsRapid load selection for back bars Refrigeration requirements for hardening ice creamSummer outside air and ground temperature design conditions DesignDry Bulb Temp State CityTemperature Difference Product Safety/Capacity ControlRefrigeration Equipment Selection Equipment BalanceDerating Factors Type of Operation/Air FlowRecommended Air Changes/Hour Effects of Altitude on Air Cooled EquipmentGeneral Guidelines Left Large cooler or freezer Right Unit Cooler Recommended Coil ReplacementLeft Cooler or freezer with glass display doors Right Line Sizing Recommended Line Sizes for R-134a+30˚F 150 200 100Expansion Valve 21/8Equivalent Lengths Recommended Line Sizes for R-22100 150 200 Receiver to 200 100Recommended Line Sizes for R-404A and R-507 Recommended Line Sizes for R-404A and R-507 30˚F 40˚FEquivalent Feet of Pipe Due to Valve and Fitting Friction Recommended Remote Condenser Line Sizes 134a R507 & R-404A Liquid Line NetRefrigerant Fahrenheit Celsius Temperature Conversion Chart CelsiusFahrenheit Celsius FahrenheitSingle Phase Loads Ohm’s Law for direct current Conversion Factors constantAir Coils = WattsEnglish Conversion Factors & Data English to Metric Conversion FactorsUse of the Psychrometric Chart DefinitionsSR/lb dry air 7000Appendix Charts Atmospheric PressureAt other altitude Courtesy of Ashrae Reproduced by permissionCourtesy of Ashrae Reproduced by permission Glossary of Refrigeration Terms Dimension Quick Selection GuideBtuh Load +35 Room +30 Room FloorTips for Quick Selection Guide Rapid Load Calculator for Large Coolers and Freezers Heatcraft Refrigeration Products LLC

H-ENGM0408, H-ENGM0806 specifications

Heatcraft Refrigeration Products offers a diverse range of commercial refrigeration solutions designed to meet various operational needs. Among their notable offerings are the H-ENGM0806 and H-ENGM0408 models, which stand out for their efficiency and innovative features.

The H-ENGM0806 model boasts a robust construction and high-performance capabilities, making it ideal for large-scale refrigeration requirements. This model is engineered with an advanced compressor that provides powerful cooling while maintaining energy efficiency. The unit operates at low sound levels, making it suitable for environments where noise reduction is essential, such as restaurants and grocery stores. Additionally, the H-ENGM0806 incorporates a reliable fan system designed to ensure optimal air circulation, promoting even cooling throughout the refrigerated space.

Meanwhile, the H-ENGM0408 model is designed for medium-sized applications that require flexibility without compromising on performance. This unit features a compact design, making it an excellent choice for businesses with limited space. Its energy-efficient compressor reduces operational costs, and its user-friendly digital controls allow for easy temperature adjustments and monitoring. The H-ENGM0408 is engineered to operate in various ambient conditions, ensuring reliability and consistent performance regardless of the environment.

Both models feature a state-of-the-art microprocessor control system that allows for precise temperature management. These systems not only optimize performance but also enhance the longevity of the refrigeration units. The H-ENGM0806 and H-ENGM0408 come with a robust evaporator coil design, facilitating rapid cooling and reducing the downtime associated with equipment maintenance.

In terms of durability, both products are constructed with high-quality materials resistant to corrosion and wear, making them suitable for demanding commercial environments. Additionally, they comply with industry standards and regulations, ensuring safety and reliability in operation.

In conclusion, Heatcraft's H-ENGM0806 and H-ENGM0408 models combine efficiency, flexibility, and advanced technology to provide reliable refrigeration solutions. Their thoughtful design and robust features make them ideal choices for businesses looking to maintain optimal temperature control while minimizing energy consumption and operational costs.