Our Nassau-based crews carry the parts and the know-how to get your air moving again today. Priority scheduling available across Nassau and the surrounding zip codes.
Call +1-866-805-8548 and describe what your system is doing — the symptoms help us send a tech prepared with the right parts.
You'll get a flat-rate quote before any repair work begins — no guessing what the final bill will look like.
Warranty details are explained clearly so you know exactly what's covered going forward.
Leonard HVAC grew one honest service call at a time in communities like Nassau. Our crews carry manufacturer certifications across the major residential and commercial equipment lines.
We're not the biggest name in Nassau — we're the company that tells you what actually needs fixing instead of what pads the ticket. Licensing and insurance aren't optional line items for us, and we keep that documentation available on request for every job, big or small.
We know which neighborhoods run on older ductwork and which subdivisions were built with newer high-efficiency systems. That local knowledge shapes how we diagnose problems — it's the difference between a tech who's guessing and a tech who's seen your exact situation a hundred times before.
Trust in this industry gets eroded fast, and it takes real consistency to earn it back. That's the gap we built Leonard HVAC to close. We track arrival windows, callback rates, and repeat-issue complaints internally so problems get caught before they become patterns, because a customer who trusts us once tends to call us again — and Nassau is a small enough community that reputation travels fast.
That local context saves time on every call, because we're not starting from zero on basic questions about your neighborhood or your system. Our warranty and service history records stay attached to your address, so any future technician who visits already has the full picture.
Every service below is backed by the same licensing, warranty, and upfront pricing you get on any job we run.
A dead system in the middle of a heat wave or a cold snap isn't just inconvenient — it can be a real safety issue for kids, pets, and older residents. Our Nassau dispatch team moves emergency tickets to the front of the schedule so a technician is diagnosing your system as fast as physically possible.
We keep the truck stocked with the parts that fail most often on the equipment common to Nassau homes, which is exactly why most repairs don't require a return visit.
If your unit is past its expected service life, running loud, or spiking your utility bill, a replacement conversation is worth having. We walk Nassau homeowners through financing and rebate options where available before a single piece of equipment gets ordered.
Every install ends with a performance test, confirming airflow, temperature split, and refrigerant charge are all where they should be before we consider the job finished.
Commercial equipment operates differently than a residential unit, and it needs technicians who actually understand rooftop packages and multi-zone systems. Our commercial division services light industrial and warehouse ventilation across Nassau, with after-hours work to avoid disrupting business.
We understand that a commercial call isn't just about comfort, it's about keeping a business open.
A seasonal tune-up catches the kind of wear that turns into a mid-summer no-cool call. Beyond standard tune-ups, we also handle duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces for Nassau households that want more than just temperature control.
Maintenance plan members in Nassau get scheduling reminders automatically, so tune-ups don't fall through the cracks during a busy season.
We'd rather set clear expectations upfront than make vague promises we can't back up.
Details vary by job type and are always shared upfront, never buried in fine print.
We quote a flat rate before work begins and that number doesn't change once you approve it.
If anything feels off after we leave, one call gets a tech back to your Nassau address.
A little attention to how your system is running can save you a lot of money and discomfort.
Rattling during startup often means a component has worked itself loose and needs tightening before it causes real damage.
If some rooms stay hot or cold no matter what the thermostat says, the system may be struggling to distribute air evenly.
A system working harder than it should to hit the same temperature shows up directly on your utility bill.
This is one of the warning signs we recommend not waiting on.
A burning smell should never be ignored — it can indicate an electrical issue that needs immediate attention.
We'll always tell you honestly when a repair is the better call versus when it isn't.
No inflated "emergency surcharge" games — the number we quote is the number you pay.
Because our trucks are stationed near Nassau, we're rarely far from your address.
Parts and labor are backed by warranty terms explained in plain language.
Our techs recognize brand-specific quirks instead of learning your system on the job.
We explain what failed, why it failed, and what the options are.
Replacement systems don't have to be paid in one lump sum.
We don't write these — our customers do.
"The furnace stopped working overnight and someone was at our door before 9am. The pricing was exactly what they quoted over the phone."
"Signed up for the annual plan after our first repair and it's paid for itself already. Never once felt like I was being upsold on something I didn't need."
"They handled the whole install in a single day, exactly like they said they would. Would recommend to anyone in Nassau needing a real replacement, not a patch job."
"As a property manager, having a company that actually answers after-hours calls is rare. Kept our kitchen running through the weekend rush."
"The estimate matched the final invoice exactly, down to the dollar. Installation crew was in and out in a day and left the space cleaner than they found it."
"Diagnosed a failed capacitor and had it swapped within the hour. Genuinely relieved to have found a crew that answers when it matters."
After thousands of service calls across Nassau, a handful of causes show up again and again.
Nassau's seasonal swings put real stress on a system that isn't maintained regularly. Filters should be checked monthly during heavy-use seasons and replaced roughly every 60-90 days depending on your household and any pets.
Clearing debris, leaves, and overgrown landscaping away from an outdoor condenser unit gives it room to breathe and keeps it running efficiently. None of this replaces a professional tune-up, but it does reduce the wear that leads to premature breakdowns between visits.
Whether your Nassau home has a traditional split system, a ductless mini-split, a heat pump, or a hybrid dual-fuel setup, our crews are equipped to diagnose and repair it. If your system was installed by a different company entirely, that's not a problem — we service equipment regardless of who originally put it in, and we'll pull the model and serial information to confirm parts compatibility before any repair begins.
We don't outsource dispatch to a call center that's never met our technicians.
Over a decade in residential heating and cooling, with a focus on load calculations and full system replacements.
Keeps the emergency truck stocked based on what actually fails most often locally.
Focuses on commercial rooftop units, multi-zone systems, and facility maintenance contracts.
For emergency no-heat or no-cool calls, we prioritize dispatch and aim to have a technician on-site the same day, often within a couple of hours.
Our policy is simple: you approve the number before we touch the system.
Yes, no-heat and no-cool situations are treated as priority calls regardless of the hour.
We maintain current credentials because it protects both our customers and our team.
Our technicians walk you through the actual numbers — repair cost versus remaining system life versus new equipment efficiency — before making a recommendation.
Yes, our maintenance plans include seasonal tune-ups, priority scheduling, and discounted repair rates for members.
If you're unsure whether your address falls in our service area, a quick call to +1-866-805-8548 will confirm it.
Yes, we run separate residential and commercial divisions, both fully licensed and equipped for their respective equipment.
Yes, we service systems regardless of who originally installed them.
We understand a full system replacement is a significant expense, which is why flexible payment options exist.
Most Nassau homes benefit from two tune-ups a year — one before cooling season and one before heating season.
Check that the thermostat has power and the batteries aren't dead, and check your breaker panel for a tripped switch before calling.
We'd rather quote it honestly on the phone than have you feel ambushed by the bill.
More involved repairs, like a coil replacement or a refrigerant leak repair, take longer and the tech will give you a realistic estimate before starting.
For most residential visits, yes, an adult should be present to grant access and approve any quoted work.
Housing stock varies a lot across Nassau — older homes often still run original ductwork that needs different care than the sealed, high-efficiency systems going into newer builds.
If you manage several units or a shared system across a Nassau property, ask about setting up a standing service account so every request gets handled under one consistent agreement.
We accept standard payment methods for repairs and smaller jobs, and we'll always tell you upfront what a given service is likely to cost so there's no last-minute scramble to figure out payment. If a rebate or local incentive program applies to your Nassau installation, our technicians will flag it during the estimate rather than leaving you to track it down after the fact.
Coverage extends across Nassau proper and into the nearby zip codes listed below.
Coverage isn't limited to a single neighborhood or subdivision — our Nassau dispatch zone stretches across the metro area and into the surrounding suburbs and unincorporated communities.
