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It sounds like you want to simulate an air-to-water heat pump using the HeatPump:PlantLoop:EIR:Cooling object in EnergyPlus for a heat pump that produces chilled water while rejecting heat to air (likewise the companion HeatPump:PlantLoop:EIR:Heating object for producing hot water). This was added to EnergyPlus in v9.3 which was released in March 2020, so you would need to use the OpenStudio Application v1.0.0 or later. The Notable Changes section doesn't mention adding this capability to the application, and neither does the release notes for OpenStudio Application v1.1.0. In the OpenStudio Application v1.1.0, it doesn't appear that the HVAC library includes this option -- just the water-to-air heat pump coil or the water-to-water heat pump coil (see below).

image description

If you wanted to stay in OpenStudio, you could write a measure using the OpenSTudio SDK. However, the SDK does not include any methods related to this air-to-water heat pump object in EnergyPlus, so that is not an option either.

It looks like you will need to export an EnergyPlus input file (IDF) from OpenStudio and manually edit to add this air-to-water heat pump object.

If you wanted to stick with OpenStudio, an alternative method is mentioned in this EnergyPlus feature request for the air-to-water heat pump:

Current work around is to use a heat pump water heater, which is really inteded for domestic hot water, along with an air-cooled chiller. This is an air-source central heat pump and differs from the existing CentralHeatPumpSystem in that it is water-source).

Both of those HVAC components are available in the OpenStudio Application.

It sounds like you want to simulate an air-to-water heat pump using the HeatPump:PlantLoop:EIR:Cooling object in EnergyPlus for a heat pump that produces chilled water while rejecting heat to air (likewise the companion HeatPump:PlantLoop:EIR:Heating object for producing hot water). You can read more about this EnergyPlus capability in this Unmet Hours post.

This was added to EnergyPlus in v9.3 which was released in March 2020, so you would need to use the OpenStudio Application v1.0.0 or later. The Notable Changes section doesn't mention adding this capability to the application, and neither does the release notes for OpenStudio Application v1.1.0. In the OpenStudio Application v1.1.0, it doesn't appear that the HVAC library includes this option -- just the water-to-air heat pump coil or the water-to-water heat pump coil (see below).

image description

If you wanted to stay in OpenStudio, you could write a measure using the OpenSTudio OpenStudio SDK. However, the SDK does not include any methods related to this air-to-water heat pump object in EnergyPlus, so that is not an option either.

It looks like you will need to export either. According to this Unmet Hours post, the openstudio-standards gem has a method to apply a central air-to-water heat pump that might work for you. If not, you have two other options:

  1. Export an EnergyPlus input file (IDF) from OpenStudio and manually edit to add this air-to-water heat pump object.

    If you wanted to stick with OpenStudio, an

  2. An alternative method is mentioned in this EnergyPlus feature request for the air-to-water heat pump:

Current work around is to use a heat heat pump water heater, which is really really inteded for domestic hot water, along along with an air-cooled chiller. This is an an air-source central heat pump and and differs from the existing existing CentralHeatPumpSystem in that it is water-source). is water-source).

Both of those HVAC components are available in the OpenStudio Application.