Our Hazelwood-based crews carry the parts and the know-how to get your air moving again today. Same-day appointments available across Hazelwood 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.
Ask as many questions as you want; we'd rather over-explain than leave you unsure.
Warranty details are explained clearly so you know exactly what's covered going forward.
Leonard HVAC didn't start as a franchise chasing volume. Our crews carry manufacturer certifications across the major residential and commercial equipment lines.
You won't find us buried under layers of call-center scripts — we're the crew that answers the phone at 2am when your furnace quits in the middle of a cold snap. We carry the credentials Hazelwood inspectors and property managers expect to see, and we keep that documentation available on request for every job, residential or commercial.
Hazelwood'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.
Ask around Hazelwood and you'll hear the same complaint about a lot of HVAC companies. That's the gap we built Leonard HVAC to close. Every dispatcher, every technician, and every follow-up call is held to the same standard, because a customer who trusts us once tends to call us again — and Hazelwood 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 Hazelwood homes, and realistic scheduling given local demand. We keep parts inventory stocked based on what actually fails most often on Hazelwood's housing stock.
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 Hazelwood 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 Hazelwood 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 Hazelwood homeowners through load calculations so the new system is sized correctly for the actual square footage before a single piece of equipment gets ordered.
Most installs in Hazelwood are completed in a single day, and we walk you through the new thermostat and any app controls before we leave.
Downtime in a commercial space costs money every hour a system is offline. Our commercial division services light industrial and warehouse ventilation across Hazelwood, 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.
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 indoor air quality upgrades for homes with allergy or asthma concerns for Hazelwood households that want more than just temperature control.
We'll show you photos of anything concerning we find, along with a plain-language explanation of what it means and whether it's urgent.
Guarantees only mean something if a company actually honors them, so here's exactly what ours covers.
If the same issue returns within the warranty period, we come back and fix it at no additional labor cost.
We quote a flat rate before work begins and that number doesn't change once you approve it.
Our office follows up after major repairs and installs to confirm everything is holding.
Most breakdowns don't happen without warning — they announce themselves for weeks before the system actually quits.
Ignoring new noises is one of the fastest ways to turn a small repair into a major one.
If some rooms stay hot or cold no matter what the thermostat says, the system may be struggling to distribute air evenly.
A tune-up often identifies exactly what's driving the extra energy use.
A system that won't hold a steady cycle is often fighting a sizing issue, a thermostat problem, or a refrigerant imbalance.
Chemical odors may signal a refrigerant leak, which requires a licensed technician to handle safely.
Repeated repairs on an aging system are usually the clearest sign that replacement will save more money than another patch job.
We explain diagnostic fees and repair estimates before authorizing work.
Emergency calls get moved to the front of the line automatically.
If something isn't right after we leave, we come back and make it right.
Our techs recognize brand-specific quirks instead of learning your system on the job.
You make the final call — we just make sure you have the full picture.
Maintenance plan members get priority scheduling and discounted rates.
We don't write these — our customers do.
"I called three other companies first and this was the only one that actually picked up. The pricing was exactly what they quoted over the phone."
"Scheduled a fall tune-up and they caught a cracked part before it became a real problem. Never once felt like I was being upsold on something I didn't need."
"Explained the sizing calculation so I understood why they weren't just installing the same unit again. Followed up a week later just to check everything was still running fine."
"Commercial dispatch was quick and the tech understood our system without needing to be walked through it. Documentation for our records was thorough and easy to file."
"I appreciated that they didn't try to sell me a bigger unit than I needed. Would use them again without hesitation."
"Called at 11pm during a heat wave and honestly didn't expect anyone to pick up, let alone show up. No overnight surcharge shock — the price matched what dispatch quoted me on the phone."
Understanding what typically fails helps homeowners know what to watch for and when a repair call is worth making before things get worse.
Hazelwood's seasonal swings put real stress on a system that isn't maintained regularly. 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.
Simple habits between professional visits also matter. None of this replaces a professional tune-up, but it does reduce the wear that leads to premature breakdowns between visits.
Our technicians train across the major residential and commercial equipment lines, so you're not limited to a single brand's service network. 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.
Here's a look at the kind of experience that shows up at your door.
Over a decade in residential heating and cooling, with a focus on load calculations and full system replacements.
Known for fast, accurate diagnostics on no-heat and no-cool breakdowns.
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.
We staff after-hours dispatch specifically because HVAC failures rarely happen on a convenient schedule.
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.
Our dispatch area extends throughout the greater Hazelwood region and nearby towns within Hazelwood, MO.
Property managers and business owners can request a dedicated point of contact for ongoing service.
Our technicians are trained across the major residential and commercial equipment lines, not limited to a single manufacturer.
Financing options are available for qualifying replacement installations, and our team can walk you through what's currently offered.
Most Hazelwood 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.
Ask about current after-hours rates when you call +1-866-805-8548.
Most standard repairs are completed in under two hours once the technician has diagnosed the issue and you've approved the quote.
For most residential visits, yes, an adult should be present to grant access and approve any quoted work.
Our technicians are familiar with both, which means less time spent figuring out your specific setup and more time actually fixing the problem.
Larger properties get the same upfront pricing and licensed technicians as a single-family service call, just coordinated at scale.
Qualifying installations can be financed through options we'll walk you through during your in-home estimate, with terms explained clearly before you commit to anything. If a rebate or local incentive program applies to your Hazelwood installation, our technicians will flag it during the estimate rather than leaving you to track it down after the fact.
We dispatch throughout Hazelwood and the neighboring communities, keeping response times tight because our trucks stay close to home.
If you're on the edge of our listed zip codes, it's still worth a call, since routes and coverage get adjusted as demand shifts.
