AHU & TFA Modeling in DesignBuilder – Coil Availability and Setpoint Manager Query

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For an office project, we have cooling during February–November and heating during December–January. The system uses:

1. 4-coil AHU (water-based cooling coil + water-based heating coil connected to heat pump)
2. Separate TFA unit with DX cooling coil, HRW, and prefilters
3. Water-cooled chillers for cooling

In DesignBuilder, we are modelling this by introducing the TFA components into a single AHU template, along with the water-based coils positioned before the fan. Cooling and heating schedules have been provided as per seasonal operation.

My questions:

1. Availability Schedules: Should the cooling coil and heating coil availability schedules inside the AHU be kept ON 24/7, or should they follow the same seasonal operation schedule as the cooling/heating mode?

2. Setpoint Managers: Do we need to switch the setpoint managers between cooling SAT and heating SAT according to the months (Feb–Nov for cooling, Dec–Jan for heating), or does DB handle this automatically?