Sun’s out, AC’s on
Here's how most summer comfort complaints happen.
An air handler runs all winter on heating mode. Nobody checks the cooling coil, the economizer damper, or the condensate drain. Cooling season starts. The system runs. The complaints begin.. slowly at first, then every day, then from the tenant on first floor to the to the top floor corner office.
The property managers who have quiet summers didn't get lucky. They did the unglamorous work in May - the startup sequences, the engineer conversations, and system checks.
Why May Is the Decision Window
The cooling season failure pattern is consistent across every building type and market: problems are baked in during startup and felt during peak load.
By the time a tenant calls about comfort in July, the cause is usually something that was visible in May - a dirty coil, a misconfigured BAS schedule, a cooling tower that wasn't properly commissioned, a filter that was overdue when cooling started.
Last summer's complaint log is this summer's roadmap.
Pull it now. Which floors had repeat calls? Which zones never fully resolved? Which vendor was called more than twice for the same issue? That's where this summer's problems are already growing.
The most useful thing you can do this week: ask your engineer what last summer's unresolved issues were - before they become this summer's emergencies.
The Sequence of Operations Test
Most property managers hand off cooling startup to engineering entirely. That's appropriate - it's an engineering function. But handing it off without understanding what "done" means is how problems get missed.
Sequence of operations is how your building automation system runs cooling: when it enables chillers, how it stages equipment, what it does when temperatures deviate, how it handles economizer transitions, what setpoints it uses and when.
The problem: last year's BAS scheduling assumptions are wrong this year. Tenants moved. Occupancy patterns changed. Someone adjusted setpoints during a cold snap and never changed them back. The system is running on last year's reality.
Ask Your Engineer These Questions Before Enabling Cooling
What failed last summer, and was the root cause actually fixed or just managed?
Which floors had repeat comfort complaints, and do we understand why?
What equipment is running close to capacity and what's the plan if it degrades under peak load?
Have BAS setpoints been reviewed for current occupancy patterns?
When were economizer dampers last verified to be functioning correctly?
These aren't gotcha questions. They're the questions that separate a startup from a readiness confirmation.
The Cooling Tower - Your Highest-Risk Startup
The cooling tower is the most underestimated piece of equipment in most commercial buildings. It's outside, it runs seasonally, and when it works nobody thinks about it. When it doesn't, or when it creates a water quality event, everyone does.
Startup is the highest-risk period. Water that sat stagnant over winter is a biofilm and Legionella growth opportunity. The first time the tower runs is when that risk is highest.
What Must Happen Before the Tower Runs
Basin cleaning - sediment, biofilm, and debris removal from over-winter stagnation
Water treatment program activation - biocide, scale inhibitor, corrosion inhibitor, proper bleed-off rate
Drift eliminator inspection - these reduce water loss and aerosol; damaged ones increase Legionella risk
Fill media inspection - look for scaling, fouling, or physical damage from winter
First water sample after startup - don't wait for the quarterly schedule
The question every property manager should ask their water treatment vendor: "When was the last sample taken, what did it show, and what's the treatment protocol for startup?"
ASHRAE Standard 188 establishes minimum requirements for Legionella risk management in building water systems. If your building doesn't have a Water Management Plan that covers cooling tower startup, that's a conversation to have with your engineer and water treatment vendor this month.
The AHU Checklist - The Unglamorous Work That Prevents July Emergencies
Air handling units don't fail dramatically. They degrade quietly - a dirty filter here, a worn belt there, a condensate drain that's been partially blocked for two seasons. By the time the tenant calls, the unit has been struggling for weeks.
Here's what should be confirmed before peak cooling load:
Filters: Overdue filters don't just reduce air quality. They restrict airflow across the cooling coil, reduce cooling capacity, and drive up energy cost. Change them before cooling season, not during it.
Coils: Dirty cooling coils can reduce capacity by 20–30%. They also freeze up more easily, which generates after-hours emergency calls. A coil cleaning in May costs a fraction of what an emergency service call costs at 4pm on a Friday in August.
Belts and Bearings: A worn belt costs $30 to replace on a scheduled PM. It costs $300 to replace when it snaps at 2pm during peak occupancy and you're getting calls from four floors at once. Bearings are the same story - early detection through sound and vibration, late detection through failure.
Condensate Drains: The single most preventable source of water damage in mechanical spaces. Condensate drain pans back up, overflow, and cause ceiling tile collapses and water damage in tenant spaces. Pour a gallon of water in the drain pan right now. If it doesn't drain freely, you have a problem that costs $0 to fix today and potentially thousands to fix in July.
Economizer Dampers: The most frequently misconfigured component in commercial HVAC. An economizer stuck open in summer overloads your cooling system. Stuck closed, and you're missing free cooling during shoulder seasons. Verify operation before cooling season, not during it.
The Tenant Communication You Send This Week
Most property managers send tenant communications after problems start. The leaders who build the best tenant relationships send them before.
A brief proactive communication in May sets the tone for the entire summer. It tells tenants you're paying attention. It explains the seasonal transition. It sets expectations for response times and the correct channel for comfort complaints.
It doesn't need to be long. It needs to be specific.
"As we transition into cooling season, our team is completing HVAC startup inspections and system testing. If you experience any comfort concerns, please submit a work order through [system] or contact [name] directly at [contact]. We'll have enhanced monitoring in place through the first two weeks of the transition."
That communication is 60 words. It takes 10 minutes to write and send. It prevents a dozen calls from tenants who didn't know who to contact or what to expect. Also, this is a great time to remind tenants about sever weather procedures or upcoming projects and events.
Three Questions to Ask Your Engineer This Week
1. "Which piece of cooling equipment are you most concerned about going into summer?" This question gives your engineer permission to tell you what they're already thinking about. The honest answer is more useful than any report.
2. "What are we doing differently this year based on last summer's performance?" This tells you whether last summer's problems were actually addressed or just survived.
3. "If we have a hot call at 2pm on a Thursday in July, what's most likely to be the cause?" Your engineer knows. They're usually right. Whatever they say is where to focus your startup energy now.
The best cooling seasons aren't managed in July. They're set up in May.
The unglamorous work - the filter check, the coil cleaning, the cooling tower commission, the BAS schedule review, the three questions you ask your engineer is the work that separates a quiet summer from one that costs you sleep, credibility, and a lot of after-hours service calls.
Do it now. Your July self will not remember to thank you. They'll just wonder why the summer went so smoothly.
What cooling issue from last summer does your building still not have fully resolved?
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