New York City summers have always been unforgiving, humid, relentless, and capable of turning a poorly maintained apartment into a genuine health hazard. But 2026 raises the stakes in a way no previous summer has. A severe and prolonged heat wave in June 2025 resulted in 19 heat stress deaths, and most people who died were exposed to dangerous temperatures in homes without air conditioning. That public health reality prompted the City Council to act: on January 17, 2026, New York City enacted the “Cool Homes for All” Act (Local Law 23 of 2026), making cooling a legal right for the first time in the city’s history. For property owners and managers, a working, well-maintained air conditioner is no longer just a comfort feature, it is a legal obligation, and the deadline to comply is coming faster than many realize.
The New Legal Reality: What “Cool Homes for All” Means for Property Owners
On January 17, 2026, the New York City Council enacted Local Law 23 of 2026, adding a cooling requirement to the Housing Maintenance Code similar to the existing heat and hot water rules.The law is officially known as Int. 994-A, the “Cool Homes for All” Act, and it reshapes what landlords are legally required to provide and maintain in every residential building across the city.
The law requires landlords of both market-rate and rent-stabilized apartments to provide and maintain air conditioning units for any tenant who requests them. The temperature standard is specific: during the summer, from June 15th through September 15th, rooms where tenants sleep must be no higher than 78°F when the outdoor temperature exceeds 82°F.
What Landlords Must Do Before June 15 Each Year
The maintenance obligation is not passive. Landlords must inspect the AC once a year at least 30 days before June 15th to make sure the AC unit can maintain the required temperature. That makes May 15 the practical hard deadline for annual AC inspections in every covered building, not a recommendation, but a legal requirement tied to cooling season.
Property owners who miss the compliance deadlines face fines of $1,250 per day. At that rate, a building that enters cooling season without documented inspections and functioning units can accumulate tens of thousands of dollars in penalties within a single month.
Full enforcement won’t begin until June 1, 2030, and landlords can apply for a hardship waiver that extends that timeline in increments of two years. But the annual inspection obligation is active now. Buildings that establish compliant maintenance records in 2026 are building the documentation trail that protects them at full enforcement.
Why NYC’s Heat Is Unlike Anywhere Else
On average, more deaths occur related to heat, annually in New York City and the United States, than as the result of any other extreme weather event. New York City is particularly susceptible to this hazard due to its dense urban environment and the materials used to support the built environment, which absorb and trap heat.
The urban heat island effect is not abstract, it is measurable and significant. A study of 50 major U.S. cities shows an average surface urban heat island intensity of 2.88°C, with most cities experiencing a decades-long intensification trend. In dense built environments like Manhattan or the South Bronx, where concrete, asphalt, and glass dominate the landscape, ambient temperatures can be meaningfully higher than the surrounding region, and those temperatures don’t drop at night the way they do in less developed areas.
Nearly 500 New Yorkers die from heat-related causes every year. The vast majority of those deaths occur indoors, in homes without functioning air conditioning. That is the public health context that drove Local Law 23, and it is the same context that makes AC maintenance, not just AC ownership, a genuine life-safety issue in New York City.
The Most Common AC Problems in NYC Buildings and What They Actually Cost
Understanding what goes wrong and why is the first step to preventing it. NYC buildings present specific maintenance challenges that make proactive service especially important.
Clogged Condensate Drain Lines
Most summer water-leak emergencies in NYC apartments, the kind that damage hardwood floors and require building incident reports, are caused by clogged drain lines that would have been cleared during routine maintenance. In the humid New York summer, algae and slime grow inside the condensate drain tube. When this clogs, water backs up into the indoor unit and drips onto floors or walls, one of the most common service calls in NYC during summer.
Left unaddressed, a clogged condensate line becomes a water damage claim. And water damage in a multifamily building rarely stops at one apartment it migrates through floors and ceilings, multiplying the cost.
Dirty Filters and Reduced Efficiency
A well-maintained HVAC system runs 15–25% more efficiently than a neglected one, that’s $200–$500+ saved per year on energy bills alone. A dirty filter is the single most common cause of that efficiency loss. A dirty air filter will reduce airflow to your system, which can result in a variety of problems including frozen evaporator coils, dirty air ducts, clogged condensate drain lines, insufficient cooling, and higher energy bills.
For a building with multiple units, the cumulative energy waste from unmaintained filters across an entire floor is significant and entirely preventable.
Mold Growth in NYC’s Humid Conditions
Mold is not a hypothetical risk in New York, it is a documented building issue that flourishes in the combination of summer humidity, poor AC drainage, and the limited ventilation common in older pre-war construction. Mold growth is common in NYC’s humid environment inside AC units, and a unit that is leaking or operating with poor drainage creates ideal conditions for mold to establish itself in walls and ceilings, conditions that trigger HPD violations, tenant complaints, and remediation costs far exceeding any preventive maintenance expense.
System Lifespan
85% of HVAC repairs are preventable with regular maintenance. The average HVAC system lasts 15–20 years with maintenance, but only 10–12 without it. In a city where replacement HVAC work involves building permits, licensed contractors, and often co-op or condo board approvals, shortening a system’s useful life by five to eight years is a significant capital cost, one that routine maintenance directly prevents.
The NYC AC Maintenance Schedule: What Needs to Happen and When
Filters should be checked every 1–3 months, while coils and drains should be cleaned every 6 months and annually. For NYC specifically, the density and particulate load of urban air accelerates buildup, NYC apartments collect dust faster than suburban homes due to dense urban air, building HVAC stack effects, and apartment usage patterns.
The complete maintenance calendar for NYC residential buildings breaks down as follows:
Monthly (DIY): Check and clean or replace air filters. In the summer, filters should be replaced every 30–90 days, depending on the type. Never wait more than 90 days. This is the single highest-impact maintenance action an owner or tenant can take, and it costs almost nothing.
Pre-Season (Before June 15 — Now a Legal Requirement): Full unit inspection, condensate drain flush, coil cleaning, refrigerant check, electrical connections test, window seals inspection. This is the annual inspection that Local Law 23 now mandates at least 30 days before June 15.
Mid-Season Check: Verify the unit is maintaining the legally required 78°F maximum in sleeping areas when outdoor temperatures exceed 82°F. Document the check. If the unit cannot maintain the required temperature, the landlord must act immediately.
Annual Professional Service: A complete AC maintenance visit usually lasts 1–2 hours and costs between $65–$200. This investment pays for itself by preventing emergency repairs and ensuring your system runs efficiently. For complex systems central air, through-wall units, rooftop condensers, professional service is not optional. Critical maintenance tasks like checking refrigerant levels, inspecting electrical components, and deep cleaning coils should be left to a licensed professional to ensure safety and prevent system damage.
Landlord and Tenant Responsibilities: Who Owns What
The legal landscape for AC maintenance in NYC involves layered responsibilities that differ depending on the type of unit and the terms of the lease or governing documents.
If the lease explicitly requires the landlord to provide or maintain air conditioning, the landlord must comply and make timely repairs. Even if the lease does not mention AC, an owner who supplies a working unit at move-in generally must keep it in repair for the tenancy.
Under Local Law 23, the obligation is now broader: landlords must provide and maintain units upon tenant request, regardless of what the lease says about AC. For tenants who already have units supplied by their landlord, that maintenance obligation now has a statutory backing it never had before.
For window units that tenants supply themselves: unless their lease states otherwise, renters in New York City bear the responsibility of purchasing and installing their own window air conditioners and brackets. In buildings taller than six stories, tenants must use air conditioner brackets, a safety requirement that is strictly enforced in high-rise residential buildings.
When something goes wrong, and a landlord-supplied unit fails to cool to the legally required temperature, if a landlord fails to maintain the cooling system you had when you moved in, you can file a complaint with DHCR. DHCR may freeze or reduce your rent until the landlord corrects the problems.
Practical Steps for Property Owners and Managers
If you manage residential buildings in New York City, the combination of Local Law 23’s new requirements and the city’s documented heat mortality record makes 2026 the year to formalize your AC maintenance protocol. Here is where to start:
- Document your annual inspection: The law requires inspection at least 30 days before June 15. Keep written records, the date, the technician, and the outcome, for every unit. This documentation protects you in enforcement proceedings and establishes your maintenance history ahead of the 2030 full-enforcement date.
- Schedule before the rush: HVAC companies get very busy once the first heat waves hit. Booking in March or April usually means shorter wait times and more scheduling flexibility. If you haven’t scheduled yet for 2026, the window for pre-season pricing and availability is already closing.
- Flush condensate drains before June 15: This single action prevents the most common category of summer water damage in NYC multifamily buildings. It should be part of every pre-season service call.
- Establish a filter-check protocol: Building supers or managing agents should verify filter condition in landlord-supplied units during their regular building checks. A clogged filter is a $5 problem that becomes a $500 repair if left unaddressed through July.
- Know your electrical infrastructure: Some older buildings do not have sufficient electrical outlets or electrical capacity to support modern air conditioning units. If your building is pre-war construction and you’re receiving new AC requests under Local Law 23, an electrical assessment may be a necessary first step before installation.
How DOME Handles AC Maintenance for the Properties We Manage
At DOME Property Management, we have managed New York City residential properties since 1987, through every update to the Housing Maintenance Code, every new habitability requirement, and every summer that has pushed buildings and their systems to their limits.
Local Law 23 of 2026 is the most significant change to residential cooling obligations in the city’s history. Our team is already integrating the new annual inspection requirement into our pre-season schedule for every affected building we manage, ensuring that inspections happen before the May 15 practical deadline, that documentation is maintained, and that any unit unable to meet the 78°F standard is serviced before cooling season begins.
Whether you are a condo or co-op board evaluating your compliance readiness, an individual property owner navigating the new law, or a landlord who needs a management partner with the vendor relationships to execute inspections across multiple units, we are here. Use Ask The Dewitts, our AI Chatbot available 24/7, for immediate answers to property management questions, or contact our team directly.
Visit DOMEgroup.com or email us at properties@DOMEproperty.com.
Just Dewitt. DOME Property Management — New York City property management since 1987.