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.
Our Hazelwood dispatcher asks a few quick questions to gauge urgency and get you the fastest available window.
Ask as many questions as you want; we'd rather over-explain than leave you unsure.
If anything feels off after we leave, a follow-up call gets a technician back out to make it right.
Leonard HVAC was built by technicians who got tired of watching homeowners get oversold. Our crews carry manufacturer certifications across the major residential and commercial equipment lines.
We're not the biggest name in Hazelwood — 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 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. 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.
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.
We cover the full range of heating, cooling, and air quality work Hazelwood properties actually need.
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 prioritizes no-heat and no-cooling calls 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.
An aging system that's constantly breaking down usually costs more to keep patching than to replace. We walk Hazelwood homeowners through efficiency ratings and how they translate into real monthly savings before a single piece of equipment gets ordered.
We protect floors and entryways during the install and haul away the old equipment so you're not left dealing with disposal.
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 duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces 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.
We'd rather set clear expectations upfront than make vague promises we can't back up.
Every repair comes with a workmanship warranty explained in plain terms before we leave.
If a competitor's written quote for the same scope of work is genuinely lower, ask us about it.
Our office follows up after major repairs and installs to confirm everything is holding.
Catching these signs early usually means a same-day repair instead of an emergency call at the worst possible moment.
Ignoring new noises is one of the fastest ways to turn a small repair into a major one.
This is one of the most common complaints we hear on service calls across Hazelwood.
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.
Chemical odors may signal a refrigerant leak, which requires a licensed technician to handle safely.
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.
Dispatchers give you a realistic arrival window instead of a vague "sometime today".
Parts and labor are backed by warranty terms explained in plain language.
We run background checks because you're letting someone into your home.
You make the final call — we just make sure you have the full picture.
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. Fixed on the first visit and explained everything in terms I could actually understand."
"We've used them for our maintenance plan for two years now and never had a surprise breakdown. You can tell these guys actually know what they're doing."
"Had a full system replacement done and it was the smoothest home project I've had in years. Followed up a week later just to check everything was still running fine."
"Our restaurant's rooftop unit went down on a Friday night and they had someone out fast. Now our go-to for every property in the portfolio."
"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."
"Called at 11pm during a heat wave and honestly didn't expect anyone to pick up, let alone show up. Genuinely relieved to have found a crew that answers when it matters."
Understanding what typically fails helps homeowners know what to watch for and when a repair call is worth making before things get worse.
Homeowners who schedule a tune-up ahead of each season tend to call us far less often for emergency repairs. Filters should be checked monthly during heavy-use seasons and replaced roughly every 60-90 days depending on your household and any pets.
Setting a programmable or smart thermostat to a consistent schedule reduces the number of times the system has to work hard to catch up to a big temperature swing. 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 Hazelwood 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.
Every tech on our Hazelwood roster goes through background checks, licensing verification, and ongoing manufacturer training.
Handles the majority of Hazelwood installs and specializes in properly sizing equipment for older housing stock.
Runs point on overnight and weekend emergency calls throughout Hazelwood.
Focuses on commercial rooftop units, multi-zone systems, and facility maintenance contracts.
Because our trucks are staged near Hazelwood, average arrival windows run faster than what national chains typically offer.
We explain the diagnostic fee upfront and provide a flat-rate repair quote once the issue is identified.
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.
As a general guideline, if a system is past 12-15 years old and facing a costly repair, replacement often makes more financial sense.
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.
Our commercial team handles rooftop units, multi-zone systems, and facility contracts alongside our standard residential repair work.
If parts require special ordering for a less common brand, we'll communicate that timeline upfront.
Financing options are available for qualifying replacement installations, and our team can walk you through what's currently offered.
Systems that run harder due to heavy year-round use may benefit from more frequent check-ins.
If you smell gas or burning, shut off the system at the breaker and step outside, then call us immediately.
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.
Housing stock varies a lot across Hazelwood — 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 Hazelwood property, ask about setting up a standing service account so every request gets handled under one consistent agreement.
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.
If your address falls within Hazelwood, MO and near Hazelwood, there's a strong chance we already service your street.
Coverage isn't limited to a single neighborhood or subdivision — our Hazelwood dispatch zone stretches across the metro area and into the surrounding suburbs and unincorporated communities.
