Every TSPR building must have at least one HVAC system entered, and every block must have a Primary Heating/Cooling System assigned to it (see instructions below). Primary Heating/Cooling Systems consist of either an Air Handler or Zone Equipment component that may also have either a Plant Loop or a VRF System associated with it. View the HVAC System Types page for configuration and data entry guidelines, and the Technical Terms page for definitions of TSPR HVAC System parameters. Note that the TSPR Tool will not model unconditioned spaces (spaces with no heating and no cooling).
All building HVAC components must also have at least one equipment schedule entry (see the Mechanical Equipment page for details). Equipment schedules and HVAC components may be entered and edited from either the Mechanical Equipment screen, or the Heating and Cooling screen.
See also: TSPR Snapshot #6 - HVAC Deep Dive training video and additional videos and documentation at waenergycodes.com/online_training.
Create an HVAC system from the Heating and Cooling screen
- Select the Heating & Cooling icon from the asset score toolbar to create or edit the equipment of the HVAC system(s) supplying your building.
- Select and add HVAC components by selecting the ‘+’ (Add) icons from among the following available selections on the Heating and Cooling page. If air handlers or zone equipment are served by plant loops, then the plant loops should be created first:
- Enter a descriptive name (or use the default component text)
- Select a System Type
- Select a Cooling Source and a Heating Source and Fuel Type for Air Handlers and Zone Equipment, or Plant Type for Plants (including Fuel Type for Heating), or Reheat Source for Terminal Units for Air Handlers
- Create new Mechanical Equipment Schedule entries by scrolling back to the top of the screen and selecting the blue ‘Add Equipment’ button, or
- Assign previously created equipment by selecting the Attach icon (paper clip)
- Enter all required component values
- Select the green ‘Create’ button to add the component
Note: Previously created mechanical equipment entries will not be visible and available to attach to HVAC components unless the selected properties in Step 4 match the equipment entries. For example, an Air Handler mechanical equipment entry with a Central Furnace heating source and natural gas as the fuel type will not be visible and available to attach unless the Air Handler component also has Central Furnace selected as the heating source and natural gas selected as the fuel type.
HVAC component entries may be edited by selecting the blue "Edit" icon, and/or may be deleted by selecting the yellow "trash can" icon.
Assign HVAC components to building blocks
- Select the component from the left sidebar by clicking and holding the mouse
- Drag and drop (release the mouse click) onto a block
- Repeat until all components have been assigned to blocks
- Click on a block open an HVAC Systems window to specify a thermal zone layout and perimeter zone depth
HVAC assigned components are referred to and are listed as 'Primary Heating/Cooling Systems', except Dedicated Outdoor Air Systems (DOAS) or Exhaust Fans which are listed as ‘Ventilation Systems', or Baseboards and Radiators which are listed as ‘Secondary Heating/Cooling Systems’.
Only one HVAC system may be assigned to a block, except in the case of blocks served by DOAS systems. Blocks with DOAS systems assigned as ‘Ventilation System’ require a ‘Primary Heating/Cooling System’ to be assigned as well. The primary heating and cooling system can be a zone equipment or a single zone AHU. View the HVAC System Types and Configuration Solutions page for additional details on assigning DOAS to blocks.
Thermal Zone Layout
Thermal zones are a fundamental part of building energy simulation and can be thought of as rooms or collections of rooms inside the building that have similar thermal loads, share a common thermostat, or are served by the same HVAC system.
Data Entry Options for Thermal Zone Layout
Thermal Zone Layout – Pull-down menu selections:
Single Zone – Layout used when the floor is an open space served by a single HVAC system; this option is typically used for smaller buildings. ‘Single Zone’ will automatically be assigned and displayed as the only option by default if any façade in the block is less than 45’ in length, and the width in a block is less than 2.5 times the perimeter zone depth.
Perimeter and Core – Layout used when the floor is divided into four perimeter zones and one core zone; this option is typically used for larger buildings or for buildings with varying loads in perimeter versus core spaces. ‘Perimeter and Core’ will automatically be assigned and displayed as the only option by default if any façade in the block is less than 45’ in length.
Perimeter Zone Depth – Menu item available if perimeter and core selected as the thermal zone layout type. Enter a value in feet per the layout in the following Thermal Zone Layout figure. A perimeter zone should generally be created extending from each façade to a depth of 15 feet.
Other HVAC System Data Entry Options
Secondary Heating Fraction -- Available input if a Secondary Heating/Cooling System (Baseboard or Radiator) has been assigned to a block. A default value of 1.0 will be visible if the Primary Heating/Cooling System is a Window Air Conditioner. A default value of 0.2 will be visible and editable if the Primary Heating/Cooling System is a PTAC or FPFCU. Enter a value less than or equal to 1.0 for the fraction of heat served by the selected baseboard system.
Percent Area DCV Control -- Available input if Demand Control Ventilation has been checked for an Air Handler. Enter a value from 1-100 to represent the percentage of total area ventilated by the DCV in the block. Note: DCV Control is not modeled for Multifamily- Dwelling Units.