Our Markham-based crews carry the parts and the know-how to get your air moving again today. Same-day appointments available across Markham and the surrounding zip codes.
No automated menus for emergencies — a real person handles the call.
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 was built by technicians who got tired of watching homeowners get oversold. Every technician we send to your door is background-checked, factory-trained, and licensed to work on the systems installed throughout Markham, IL.
We're not the biggest name in Markham — we're the company that tells you what actually needs fixing instead of what pads the ticket. We carry the credentials Markham inspectors and property managers expect to see, and we keep that documentation available on request for every job, residential or commercial.
Markham's climate swings hard, and generic national playbooks don't always fit. That local knowledge shapes the maintenance schedules we recommend — 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'd rather lose a job to a lower bid than win one by cutting corners on the diagnosis, because a customer who trusts us once tends to call us again — and Markham is a small enough community that reputation travels fast.
When you call +1-866-805-8548, you're talking to someone who understands the local permitting process, the common equipment brands installed in Markham homes, and realistic scheduling given local demand. Our warranty and service history records stay attached to your address, so any future technician who visits already has the full picture.
We cover the full range of heating, cooling, and air quality work Markham properties actually need.
When your Hvac system fails without warning, waiting days for an appointment isn't an option. Our Markham dispatch team prioritizes no-heat and no-cooling calls so a technician is diagnosing your system as fast as physically possible.
Once a technician is on-site, the goal is always a same-visit repair — most emergency calls in Markham get resolved in a single trip, not a multi-day back-and-forth.
An aging system that's constantly breaking down usually costs more to keep patching than to replace. We walk Markham 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.
A retail floor, a restaurant kitchen, or an office suite can't run without stable climate control. Our commercial division services light industrial and warehouse ventilation across Markham, with service agreements built around your operating hours.
Our commercial techs are trained to work around your customers and staff, scheduling noisy or disruptive work outside peak hours whenever possible.
Preventive maintenance is the cheapest repair you'll ever pay for, because it's the one that prevents the bigger bill. Beyond standard tune-ups, we also handle duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces for Markham households that want more than just temperature control.
A tune-up typically takes under an hour and covers the checkpoints most likely to catch a problem before it becomes a breakdown.
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.
Emergency dispatch never comes with a hidden surcharge sprung on you after the fact.
Our office follows up after major repairs and installs to confirm everything is holding.
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.
A system that won't hold a steady cycle is often fighting a sizing issue, a thermostat problem, or a refrigerant imbalance.
A burning smell should never be ignored — it can indicate an electrical issue that needs immediate attention.
If you're calling about the same problem every few months, the underlying cause likely hasn't been fully addressed.
We explain diagnostic fees and repair estimates before authorizing work.
Emergency calls get moved to the front of the line automatically.
We don't consider a job finished until the system is actually performing correctly.
We run background checks because you're letting someone into your home.
We explain what failed, why it failed, and what the options are.
We'll walk you through what's actually available before you decide.
Every review below reflects an actual service call in the Markham area.
"Our AC quit on the hottest weekend of the year and they had a tech out within a couple of hours. No pressure to buy a whole new system when a repair was all we needed."
"We've used them for our maintenance plan for two years now and never had a surprise breakdown. Techs are always polite, always on time, and clean up after themselves."
"Explained the sizing calculation so I understood why they weren't just installing the same unit again. New system is noticeably quieter and our energy bill actually dropped."
"Our restaurant's rooftop unit went down on a Friday night and they had someone out fast. Kept our kitchen running through the weekend rush."
"Got quotes from four different companies for a replacement and this was the only one that actually walked me through the load calculation. My energy bill dropped noticeably the first month with the new system."
"The tech walked me through what he was checking as he went, which I really appreciated. Genuinely relieved to have found a crew that answers when it matters."
None of these are unusual or embarrassing — they're just the normal wear and tear that comes with running a system through Markham's seasonal swings.
The shift between peak heating and peak cooling demand is exactly when older or neglected equipment tends to fail. Before the coldest stretch of the year, a heating system benefits from a full safety inspection, checking the heat exchanger, ignition system, and airflow to catch any issue that could turn into a no-heat emergency.
Keeping vents unblocked by furniture and rugs helps maintain even airflow throughout the home. None of this replaces a professional tune-up, but it does reduce the wear that leads to premature breakdowns between visits.
We also service package units common on manufactured and modular homes throughout the Markham area. 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.
Runs point on overnight and weekend emergency calls throughout Markham.
Experienced with the light industrial and retail equipment common across the area.
Standard appointments are usually scheduled within 24-48 hours, while true emergencies jump the queue.
Yes — every job gets a clear quote before any repair work begins, so there are no surprise line items on the invoice.
Our emergency line runs 24 hours a day, including nights, weekends, and holidays.
We maintain current credentials because it protects both our customers and our team.
We never push a replacement when a straightforward repair will genuinely solve the problem.
Ask your technician about current plan pricing during any service call.
If you're unsure whether your address falls in our service area, a quick call to +1-866-805-8548 will confirm it.
Property managers and business owners can request a dedicated point of contact for ongoing service.
If parts require special ordering for a less common brand, we'll communicate that timeline upfront.
We understand a full system replacement is a significant expense, which is why flexible payment options exist.
Twice-yearly maintenance is the standard we recommend given the temperature swings the area sees.
Check that the thermostat has power and the batteries aren't dead, and check your breaker panel for a tripped switch before calling.
Ask about current after-hours rates when you call +1-866-805-8548.
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.
Let dispatch know ahead of time if access will be handled differently than a standard homeowner visit.
Our technicians are familiar with both, which means less time spent figuring out your specific setup and more time actually fixing the problem.
We also work regularly with homeowners associations, property management companies, and multi-unit buildings throughout Markham.
A full system replacement is one of the bigger home expenses most people face, and we don't expect everyone to pay it in a single lump sum. If a rebate or local incentive program applies to your Markham installation, our technicians will flag it during the estimate rather than leaving you to track it down after the fact.
Coverage extends across Markham proper and into the nearby zip codes listed below.
Coverage isn't limited to a single neighborhood or subdivision — our Markham dispatch zone stretches across the metro area and into the surrounding suburbs and unincorporated communities.
