Missing or Zero Loads

When loads don’t appear, are partially missing, or read zero, the cause is almost always an unassigned input rather than a calculation problem. Work through the cases below.

Loads aren’t showing at all

Loads will not generate unless each space has a space type assigned. The space type defines the design requirements (internal loads, ventilation, setpoints) and links them to the space geometry.

To fix:

1. Select a space in the Spaces pane.
2. In the Space Data sidebar, assign a space type using the dropdown.

Once space types are assigned, loads populate accordingly. See Space Types.

A space shows 0 BTU despite having exterior walls

A space can show 0 BTU even with exterior envelope components assigned if its space type has no indoor design conditions. Without a target indoor condition, HVAKR has nothing to calculate the load against.

Check that the assigned space type defines:

• Summer setpoint
• Winter setpoint
• Relative humidity

To fix:

1. Go to Basis of Design → Space Types.
2. Select the affected space type.
3. Add the summer setpoint, winter setpoint, and relative humidity values.

Loads will then calculate normally for every space using that type.

External cooling loads (walls, windows) are missing

External loads will not appear in the Cooling Sums at Peak unless the envelope types have Wall Data, Window Data, and Roof Data assigned.

To fix:

1. Go to Basis of Design → Building Data.
2. Open each relevant wall, window, and roof type.
3. Select the closest available assembly type for each data field.

Tip

The assembly does not need to be exact. HVAKR uses the approximate construction data to account for conductive and radiant time-series (thermal mass) effects — the closest available type is enough to produce results.

Once Wall, Window, and Roof Data are assigned, the external cooling loads appear in the results. See Building Data.

Infiltration CFM is lower than expected

When using a CFM-per-square-foot-of-wall-area input, reported infiltration can come in low if some spaces with exterior wall area are missing a space type.

Infiltration is only calculated for fully defined spaces. A space without a space type can still contribute its wall area to the project total, but its infiltration is excluded from the load calculation — so the totals diverge.

To fix, confirm every space with exterior wall area has a space type assigned. Once assigned, the infiltration total updates accordingly.

Note

This is the same root cause as missing loads above: an unassigned space type silently drops that space from parts of the calculation while its geometry still shows up in area totals.