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How to set up an Hybrid ventilation unit in design

Hi everyone,

I’m fairly new to detailed HVAC modeling in DesignBuilder and I’m trying to model a Heat Recovery Ventilation (HRV) unit for a project. I’ll be attaching the unit’s brochure for reference.

The HRV unit includes the following key features:

1.Heat recovery between exhaust and fresh air streams

2.Recirculation mode for energy saving in certain conditions

3.Night purge operation for free cooling during off-hours

4.Ability to modulate airflow rates based on indoor temperature, CO₂ levels, and day/night schedules

I have a few questions and would really appreciate your guidance:

a) What would be the most suitable HVAC template in DesignBuilder to begin with for modeling this type of HRV system?

b) How can I model variable flow rates based on indoor conditions like temperature and CO₂?

c) Is EMS (Energy Management System) the only way to implement this control logic?

Are there any built-in options or recommended workarounds for beginners?

Any advice or examples on modeling night purge, recirculation, or CO₂-based demand-controlled ventilation would be super helpful.

Thanks in advance for your time and help.

Link to the HVR unit- https://s3-eu-west-1.amazonaws.com/monodraught/downloads/hvr%20zero%20apx%20product%20card%202025%20v2.pdf

How to set up an Hybrid ventilation unit in design

Hi everyone,

I’m fairly new to detailed HVAC modeling in DesignBuilder and I’m trying to model a Heat Recovery Ventilation (HRV) unit for a project. I’ll be attaching the unit’s brochure for reference.

The HRV unit includes the following key features:

1.Heat recovery between exhaust and fresh air streams

2.Recirculation mode for energy saving in certain conditions

3.Night purge operation for free cooling during off-hours

4.Ability to modulate airflow rates based on indoor temperature, CO₂ levels, and day/night schedules

I have a few questions and would really appreciate your guidance:

a) What would be the most suitable HVAC template in DesignBuilder to begin with for modeling this type of HRV system?

b) How can I model variable flow rates based on indoor conditions like temperature and CO₂?

c) Is EMS (Energy Management System) the only way to implement this control logic?

Are there any built-in options or recommended workarounds for beginners?

Any advice or examples on modeling night purge, recirculation, or CO₂-based demand-controlled ventilation would be super helpful.

Thanks in advance for your time and help.

Link to the HVR unit- https://s3-eu-west-1.amazonaws.com/monodraught/downloads/hvr%20zero%20apx%20product%20card%202025%20v2.pdf