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"Ideal Air Loads" and Packaged Rooftop Heat Pump with COP of 1

I created a multi-zone single detached dwelling model in OpenStudio. I tried to run the model by using Ideal Air Loads and it gave total district heating loads of 21GJ. However, if I use a Packaged Rooftop Heat Pump for each zone and set the COP for Coil:Cooling:DX and Coil:Heating :DX to 1, the total electricity usage will be 32GJ.

Based on the result of the post: https://unmethours.com/question/4678/vrf-system-with-huge-no-of-unmet-hours-only-during-heating/

I tried to create a reasonable on/off schedule for Coil:Heating:Electric and Fan based on cooling and heating schedules, but the results didn't change.

Does anyone know why Packaged Rooftop Heat Pump with COP of 1 gives such a high heating and cooling electricity usage compared to district heating and cooling?

"Ideal Air Loads" and Packaged Rooftop Heat Pump with COP of 1

I created a multi-zone single detached dwelling model in OpenStudio. I tried to run the model by using Ideal Air Loads and it gave total district heating loads of 21GJ. However, if I use a Packaged Rooftop Heat Pump for each zone and set the COP for Coil:Cooling:DX and Coil:Heating :DX to 1, the total electricity usage will be 32GJ.

Based on the result of the post: https://unmethours.com/question/4678/vrf-system-with-huge-no-of-unmet-hours-only-during-heating/

I tried to create a reasonable on/off schedule for Coil:Heating:Electric and Fan based on cooling and heating schedules, but the results didn't change.

Does anyone know why Packaged Rooftop Heat Pump with COP of 1 gives such a high heating and cooling electricity usage compared to district heating and cooling?

"Ideal Air Loads" and Packaged Rooftop Heat Pump with COP of 1

I created a multi-zone single detached dwelling model in OpenStudio. I tried to run the model by using Ideal Air Loads and it gave total district heating loads of 21GJ. However, if I use a Packaged Rooftop Heat Pump for each zone and set the COP for Coil:Cooling:DX and Coil:Heating :DX to 1, the total heating electricity usage will be 32GJ.

Based on the result of the post: https://unmethours.com/question/4678/vrf-system-with-huge-no-of-unmet-hours-only-during-heating/

I tried to create a reasonable on/off schedule for Coil:Heating:Electric and Fan based on cooling and heating schedules, but the results didn't change.

Does anyone know why Packaged Rooftop Heat Pump with COP of 1 gives such a high heating and cooling electricity usage compared to district heating and cooling?