Do Commercial HVAC Controls Have Title 24 Requirements?

What Section 120.2 covers

A specific list rather than a general principle: thermostatic controls for each zone, criteria for zonal thermostatic controls, hotel and motel guest room thermostats, heat pump controls, shut-off and reset controls for space-conditioning systems, and automatic demand shed controls. Thermostat location itself is set by Section 120.2(a).

Because these are mandatory, they are not traded away on the performance path. A design that models well still has to meet them.

The exception worth knowing

Section 120.2(e) shut-off and setback requirements have a short list of exceptions: systems serving healthcare facilities, systems of 2 kW or less with a readily accessible manual shut-off switch, and the climate exceptions. Exception 1 covers a system that serves an area that must operate continuously, but only where that is demonstrated to the satisfaction of the enforcing agency. It is a genuine exception with a genuine justification, not a general escape for anything inconvenient to set back, and it does not name a laboratory or a museum.

VAV systems follow Guideline 36

For variable-air-volume systems the prescriptive requirements follow ASHRAE Guideline 36, which brings a defined control sequence: static pressure setpoint reset, zone controls with direct digital control, an air economizer under DDC, and supply air temperature reset.

That is a materially more sophisticated controls scope than a single-zone rooftop, and it is the reason a VAV retrofit is a controls project as much as an equipment one.

Demand responsive controls

Table D-1 in Appendix D of the standards sets out when demand responsive controls are required in nonresidential buildings. On a zoned system, enabling demand response in practice means a network adapter for each controlled room, monitored and controlled by an energy management control system.

Controls are tested, not just specified

Mechanical acceptance testing covers controls as well as equipment — the energy management control system test verifies occupancy sensors are tied into both lighting and HVAC. So the controls narrative has to hold together across two trades, and it is verified on site by a certified technician before the permit closes.

Common Title 24 Questions

1. Does replacing commercial HVAC trigger Title 24?
2. Does a rooftop unit replacement require Title 24?
3. Do heat pumps affect commercial Title 24 compliance?
4. Does adding air conditioning trigger Title 24?
5. Commercial ventilation requirements under Title 24
6. Title 24 economizer requirements

Explore Commercial HVAC

1. Demand Responsive Controls Under Title 24
2. Commercial Duct Sealing and Insulation Requirements
3. Title 24 Economizer Requirements
4. Do Heat Pumps Affect Commercial Title 24 Compliance?
5. Does Replacing Commercial HVAC Trigger Title 24?

View all Commercial HVAC guides → · Commercial Title 24 · Title 24 guide