Four Pipe Heat Pump (Cooling)

A Four Pipe Heat Pump (Cooling) consists of two separate piping systems for hot and cold water, allowing for both heating and cooling capabilities. In cooling mode, the heat pump absorbs heat from indoor spaces and releases it to the chilled water loop. This system provides efficient year-round climate control by offering both heating and cooling functionalities.

Sizing

Specify the configurations for the Sizing tab on the Four Pipe Heat Pump (Cooling) component, addressing unit efficiency, capacity, and operational controls. Detail each setting comprehensively.

Reference COP

Specify the Reference COP as the ratio of load side energy transfer to power input, denoted in [W/W].

Sizing Factor

Specify the purpose of the Sizing Factor field, enabling users to adjust unit sizing relative to plant-determined autosized flow and heat capacity.

Sizing Method

Specify the Sizing Method as Autosize or Manual. For Manual sizing, ensure all numerical fields have valid entries.

Source Reference Flow Rate

Specify the Source Reference Flow Rate, representing the nominal flow request for this heat pump unit during simulation, measured in [m3/s].

Load Reference Flow rate

Specify the Load Reference Flow rate, serving as the nominal flow request for this heat pump unit during simulation, with units in [m3/s].

Reference Capacity

Specify the Reference Capacity, representing the cooling capacity for a cooling companion heat pump and heating capacity for a heating companion heat pump, measured in [W]

Chilled Water Loop Pump Rated Power Consumption

Specify the Chilled Water Loop Pump Rated Power Consumption, a numeric field containing the pump's design power consumption in Watts. This field can be autosized for flexibility.

Chilled Water Loop Pump Rated Flow Rate

Specify the Chilled Water Loop Pump Rated Flow Rate, a numeric field with the pump's design maximum volume flow rate in cubic meters per second. This field is autosizable for adaptability.

Chilled Water Loop Pump Min. Flow Rate

Specify the Chilled Water Loop Pump Min. Flow Rate, representing the minimum volume flow rate during variable flow capacity, measured in cubic meters per second. This field is autosizable. When autosized, the Design Minimum Flow Rate Sizing Factor scales the minimum flow rate as a fraction of the Design Maximum Flow Rate.

Chilled Water Pump

Pump Speed Control

Specify the Pump Speed Control, allowing a choice between Variable Speed or Constant Speed for the pump.

Pump Rated Head

Specify the Pump Rated Head, where you set the pump head pressure in Pascals for the hot water pump.

Pump Design Min. Flow Rate Fraction

Specify the Pump Design Min. Flow Rate Fraction, determining the minimum flow rate as the product of this sizing factor and the Design Maximum Flow Rate.

Pump Motor Efficiency

Specify the Pump Motor Efficiency, a numeric field denoting the pump motor's efficiency in decimal form (0 = 0%, 1 = 100%).

Pump Control Type

Specify the Pump Control Type, offering options of Continuous or Intermittent. In intermittent operation, a variable-speed pump can shut down when there is no load on the loop. It operates continuously or intermittently based on loop conditions, selecting a flow between minimum and maximum limits to meet demand.

Pump Fraction of Motor Inefficiencies to Fluid Stream

Specify the Pump Fraction of Motor Inefficiencies to Fluid Stream, a numeric field representing the pump motor's fraction of power loss to the fluid.

Pump Design Power Sizing Method

Specify the Pump Design Power Sizing Method. Choose between Power Per Flow and Power Per Flow Per Pressure. For Power Per Flow, calculate Design Power Consumption using the sizing factor from Design Electric Power per Unit Flow Rate. For Power Per Flow Per Pressure, use the sizing factor from Design Shaft Power per Unit Flow Rate Per Unit Head, considering motor efficiency in the calculation.

Pump Design Elec. Power / Flow Rate / Pressure

Specify the Pump Design Elec. Power / Flow Rate / Pressure represents the pump's design electric power per unit flow rate per unit pressure. This input, crucial for designing power consumption, is set to autosize when using the Power Per Flow Per Pressure method. The default is 1.282051 W/((m³/s)-Pa), factoring in impeller and drive assembly efficiency.

Pump Design Elec. Power / Flow Rate

Specify the Pump Design Elec. Power / Flow Rate is utilised when Design Power Consumption is set to autosize and the Design Power Sizing Method is Power Per Flow. It allows setting the pumping system's power consumption efficiency using only the design flow rate. The default value, if omitted, is 348701.1 W/(m³/s).

Staging

Specify the staging configuration for the chiller. Staging controls the component's activity across different duty ranges. Add stages to manage each chiller's operation based on the total chilled water loop cooling demand within specific ranges.

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