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Using Availability Managers to Control Components within Systems

I am using OpenStudio 2.5.0 to model a small office building as part of a utility incentive program. For this particular program, I need to use an ASHRAE 90.1-2013 Appendix G compliant Baseline. The proposed building is in climate zone 2A, and is less than 25,000 sqft. Therefore, I am using System-4, Package Single Zone Heat Pump. One of the requirements for controls in Appendix G (G3.1.3.1 Heat Pumps (Systems 2 and 4)) states "Electric air-source heat pumps shall be modeled with electric auxiliary heat. The systems shall be controlled with multistage space thermostats and an outdoor air thermostat wired to energize auxiliary heat only on the last thermostat stage and when outdoor air temperature is less than 40°F."

I am thinking an AvailabilityManager:LowTemperatureTurnOn would probably be the most applicable control to accomplish this, but looking at the Input/Output reference, there is language suggesting this will energize the entire system, not just the electric resistance heat (Is this a correct interpretation of this component?). However, I'm looking for a way to set the electric strip heat component to only be available when OAT<40°F. Does anyone have a proven method for setting up this control?

Using Availability Managers to Control Components within Systems

I am using OpenStudio 2.5.0 to model a small office building as part of a utility incentive program. For this particular program, I need to use an ASHRAE 90.1-2013 Appendix G compliant Baseline. The proposed building is in climate zone 2A, and is less than 25,000 sqft. Therefore, I am using System-4, Package Single Zone Heat Pump. One of the requirements for controls in Appendix G (G3.1.3.1 Heat Pumps (Systems 2 and 4)) states "Electric air-source heat pumps shall be modeled with electric auxiliary heat. The systems shall be controlled with multistage space thermostats and an outdoor air thermostat wired to energize auxiliary heat only on the last thermostat stage and when outdoor air temperature is less than 40°F."

I am thinking an AvailabilityManager:LowTemperatureTurnOn would probably be the most applicable control to accomplish this, but looking at the Input/Output reference, there is language suggesting this will energize the entire system, not just the electric resistance heat (Is this a correct interpretation of this component?). However, I'm looking for a way to set the electric strip heat component to only be available when OAT<40°F. Does anyone have a proven method for setting up this control?