Reversible heat pump (Changeover)

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This air-cooled heat pump can deliver either heating or cooling, non simultaneously. The heat pump has 3 control input signals and 1 supply and return changeover pipe connection:

Control inputs:

  • Source Temperature (°C)

  • Heating activation and modulation (0-1)

  • Cooling activation and modulation(0-1)

The different parameters are listed below.

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General Configuration

Parameter

Description

Base circuit identifier

Unique ID linking the heat pump to its hydraulic circuit. It ensures the component connects correctly within the system schematic.

Environment temperature

Optional external air temperature input for air-source heat pumps. The thermal losses of the system side coil are subjected to this temperature if UA value is specified

Design configuration

Defines the design mode — typically Heating/ cooling or the maximum demand for reversible systems. It tells Hysopt to size the system for both modes.

Simulation configuration

Determines which mode leads the simulation (e.g., Heat leading means heating mode governs the control logic). If both heating and cooling request active the HP will choose the sleected mode.

Heat Pump Parameters

Parameter

Description

Identifier

Internal name for the heat pump component, automatically derived from the circuit ID.

Label

Optional descriptive name for easier identification in reports or diagrams.

Pressure drop in design

Hydraulic resistance across the heat pump at design flow, used for pump sizing and circuit balancing.

UA value indoor coil

Overall heat transfer coefficient (U·A) of the indoor coil. If set to 0, Hysopt does not consider additional system side coil losses to the environment

Capacitance indoor coil

Thermal mass of the coil, influencing transient behavior. “Auto-scaled” means Hysopt estimates it based on power and fluid volume.

Compressor configuration

Defines compressor control type — e.g., VSD 0.1 indicates a variable-speed drive with minimum speed ratio 0.1.

COP table

Reference table for coefficient of performance (COP) versus operating conditions (evaporator/condenser temperatures).

EER is related through the formula EER = COP-1

Power table

Reference table for heat pump output power versus operating conditions.

Design power

Nominal heating/cooling capacity at design conditions.

Reference evaporator temperature

Temperature at which the evaporator side performance is referenced (e.g., -10 °C for air-source heating).

Reference condenser temperature

Temperature at which the condenser side performance is referenced (e.g., 40 °C for heating mode).

Performance Outputs

Parameter

Description

Condenser power

Calculated heat output at reference conditions.

COP

Coefficient of Performance — ratio of heat output to electrical input at given conditions.

Evaporator power

Cooling capacity or absorbed heat at specified evaporator/condenser temperatures.

EER

Energy Efficiency Ratio — cooling-mode equivalent of COP, defined at cooling reference conditions.