HVAC Controls in New York: How RIB® Relays Support Commercial Buildings

As of 2024, HVAC controls in New York are shaped by Local Law 97, a new emissions law that caps carbon output for most buildings over 25,000 square feet in size. Because HVAC typically accounts for roughly 40% of a building’s energy use, they are often the primary driver of emissions. Meeting this cap means running that equipment more efficiently, which is usually done via the building automation layer that controls and monitors it. Functional Devices, Inc. manufactures devices built to do exactly that, grouped as the RIB® (Relay-In-a-Box®) Trifecta: relays, current sensors, and prepackaged power supplies.

What Local Law 97 Changes for New York HVAC Control Wiring

Local Law 97 sets an annual emissions limit and assesses a penalty of $268 per metric ton of CO2 equivalent over that limit, recurring each year the building exceeds its cap. Meeting the cap generally requires a reduction in fossil-fuel use, which pushes buildings toward electrified heating, tighter scheduling, and closer monitoring of equipment. Each of these measures adds control points: more staged equipment, more scheduled loads, and more points where the building automation system (BAS) needs to switch a load cleanly, then confirm that it responded.

Every added control point is a place where a controller output has to switch a line-voltage load while staying electrically isolated from it. That isolation is the relay’s job.

RIB® Relays for New York HVAC Controls

RIB® relays are the interface between BAS binary outputs and line-voltage HVAC load circuits, keeping the low-voltage controller isolated from the loads it drives. Selection is driven by load, coil voltage, and whether the application needs one circuit or two.

First, match the coil to the control circuit driving it (typically 24 VAC from a BAS binary output). This coil-to-control match is the first step in the process of selecting a relay, and it keeps a staged system switching reliably as more equipment comes under automated control.

Choosing the appropriate contact rating is the second step. A relay sized below the load it switches will wear out prematurely. Matching the contact rating to the load (with margin for inrush on motor circuits) is what keeps a relay in service across the cycle counts that a staged HVAC system accumulates. Where a load exceeds the ratings of even a 30A DPDT device, the relay is no longer the right interface. A contactor should be specified instead.

Relays and the Shift to Electric HVAC

The connection between relays and the LL97 emissions cap is electrification. Cutting a building’s carbon output generally means replacing gas-fired equipment with electric or heat-pump equipment, and that electric equipment typically stages on in steps that a building automation system sequences. Each step the BAS commands is a switching point, and each switching point needs a relay.

Frequently Asked Questions

Does Local Law 97 require specific relay models for HVAC controls in New York?

No. Local Law 97 sets a building-level emissions limit; it does not specify hardware. The law’s effect on control wiring is indirect: electrification and tighter scheduling add control points, and each point needs a relay sized to its load.

What coil voltage should I specify for a BAS output?

Match the coil to the control circuit driving it, which is typically 24 VAC from a BAS binary output. Where control voltage varies across a job, a universal-coil model like the RIBU1C (10–30 VAC/DC or 120 VAC) reduces the number of distinct parts to stock and specify.

Can I source relays, sensors, and power supplies from one distributor?

Yes. RIB® relays, current sensors, and prepackaged power supplies are stocked through authorized Functional Devices distributors. See Sourcing RIB® Relays in New York (link) for more information.

Do control upgrades help with Local Law 97 compliance?

Indirectly, yes. Local Law 97 caps a building’s carbon emissions, and running HVAC equipment more efficiently is one way to lower them. Control upgrades such as tighter scheduling, occupancy-based setbacks, and equipment-level monitoring are often cited as lower-cost first steps before capital equipment replacement, because they reduce energy use without requiring equipment to be swapped out.

What is a dry contact, and when do I need one?

A dry contact is a switch contact with no voltage of its own; it opens or closes a separate circuit that carries its own power. A relay provides this: the coil is energized by the control signal, and the contacts switch the load circuit independently, keeping the control side isolated from the load side. Dry-contact switching is the standard way a BAS output drives a line-voltage load without exposing the controller to that voltage.

Can one relay switch two circuits at once?

Yes, with a double-pole relay. The RIB24P30 (30A DPDT) switches two independent circuits from a single control output, which suits a stage that needs two circuits energized together or a higher-current dual-circuit load. For a single circuit, a single-pole model such as the RIB2401B (20A SPDT) is the common choice.