Commercial HVAC Controls & BMS in Southern California and Arizona

What does HVAC controls work at REE Mechanical include?

We install and service the controls that decide when, how hard, and how long commercial HVAC equipment runs. That covers building management systems, zone systems, VAV dampers, ducted fire dampers, and the thermostats, sensors, and unit controllers underneath them.

Controls is one of our four service lines, alongside emergency, maintenance, and replacement, not an add-on to them. We put controls in with new equipment and projects, and we service the controls already in the field on rooftop units up to 100 tons and split systems up to 60 tons, including systems we did not install.

The work is led by Eric Choi, our Field Service Manager and controls lead.

On new equipment, the controls scope is set while the equipment is being ordered rather than after it arrives on the roof. The installs themselves are run by Kelly Purcell, our Installation Director, whose specialty is permitting.

Why do controls matter so much on a multi-site portfolio?

By our estimate, HVAC&R accounts for roughly 60% of a typical site’s electrical energy use. Controls set how that energy is spent, so a small programming error copied across many sites becomes a large line in the budget.

Controls also decide what your team can see. A site with working controls reports run status, temperatures, and alarms. A site without them stays invisible until a store manager calls. Across dozens or hundreds of locations, that is the difference between managing equipment and chasing it.

Climate makes drift more expensive here. Southern California and Arizona sites run long cooling seasons, so a schedule that starts cooling two hours before opening, or keeps running after close, repeats that waste on most days of the year.

Is this a BMS project or a controls job?

If the work is new controls, or the problem sits at the head end or across sites, it is a building management system installation and replacement project. If existing controls at a single unit or zone are misbehaving, it is HVAC controls repair and service. Many portfolios need both.

	BMS installation and replacement	HVAC controls repair and service
Level	Building and portfolio, plus controls on new equipment	Existing units and zones
Typical trigger	New equipment, unsupported head end, sites on mixed platforms, alarms that reach nobody	Remodels, blank thermostats, sensors reading wrong
Typical work	Head-end replacement or migration, integration, standard point naming	Troubleshooting and repair of thermostats, sensors, unit controllers, economizer controls, schedules
What you get	Connected sites reporting to one head end	Each unit running to the right schedule and setpoint

What are the signs a site’s controls have drifted?

The clearest signs are equipment running outside trading hours, store staff adjusting setpoints, comfort complaints from a unit that tests healthy, and sites that report nothing until something fails.

• Schedules that were never updated after trading hours, holidays, or delivery windows changed.
• Local overrides left in place long after the complaint that caused them.
• Space or supply sensors out of calibration, so every control decision downstream is off.
• Economizers stuck open or closed, pulling in hot or cold outside air at the wrong time.
• Proprietary systems whose original vendor no longer supports them, leaving nobody able to change a setpoint.
• Fire dampers that are part of the life-safety system but sit outside any inspection scope.

What does a controls review look at?

A controls review compares how equipment is programmed to run with how the site really operates, then confirms the sensors and dampers behind those decisions are working. A sound controls program starts here.

1. Occupancy schedules against current trading hours, holidays, and deliveries.
2. Setpoints, limits, and any locked or overridden thermostats.
3. Space, supply, and outside-air sensor readings against verified measurements.
4. Economizer and damper travel.
5. Zone system and VAV damper response.
6. Whether each unit reports into a head end, and whether its alarms reach a person.
7. Ducted fire damper locations and inspection status.

How is controls work scheduled and recorded?

Controls work runs on the same terms as the rest of our service: scheduled around trading hours where it would disturb the sales floor, and reported through your IVR or work-order system like any other visit.

That matters on controls more than most work, because the changes are invisible. A new schedule or recalibrated sensor leaves no visible trace on the roof. The work order is the record of what was changed, at which unit, and why. Our technicians are factory-trained, and controls checks also fit inside any ASHRAE 180 maintenance program.

What drives the scope of a controls project?

Scope comes down to how many sites and units are involved, what is already installed, whether the current head end is worth keeping, and how much access and after-hours work the job needs.

• Portfolio size. The count of sites, units, and zones to program or connect.
• Existing platform. Open, supported systems are easier to extend than orphaned proprietary ones.
• Equipment age. Older units may need new controllers before they can report anywhere.
• Documentation. Missing point lists, wiring diagrams, or as-built drawings add discovery time.
• Access and timing. Ceiling space, roof access, and windows outside trading hours.

We do not publish pricing. Every controls scope is quoted from what the review finds at your sites.

Which codes and licenses apply to HVAC controls?

Controls work follows local building, energy, and fire codes. California’s Title 24 energy code sets controls requirements for many new and altered systems, so check current code before a project is scoped.

Fire damper inspection and testing intervals come from the fire code adopted locally; confirm them with the authority having jurisdiction. REE Mechanical Inc. holds California CSLB C20 licenses #940700 and #526944 and Arizona ROC license #365042, and we are licensed, bonded and insured.

Where do we install and service HVAC controls?

Our own technicians handle controls work across Ventura, Los Angeles, Orange, San Bernardino, Riverside, and San Diego counties, and throughout Arizona, where we hold a newer statewide license and are building out our presence.

See all service areas, including Orange County and Ventura County. Our guide to building management systems for multi-site portfolios covers the planning side, and our article on economizers on retail rooftop units explains one of the most common controls faults.

Start with a site list

Call (800) 742-0910 or send us your site list and tell us what you are seeing. Controls data also feeds HVAC asset inspection and testing for capital planning.