We fix what's broken, fast, and we don't disappear after the invoice. Emergency dispatch available across Mount Prospect and the surrounding zip codes.
No automated menus for emergencies — a real person handles the call.
Ask as many questions as you want; we'd rather over-explain than leave you unsure.
Most repairs are completed same-visit, and we test the system before we leave to confirm it's actually holding.
Leonard HVAC grew one honest service call at a time in communities like Mount Prospect. We invest in ongoing training so our techs recognize a failing capacitor, a cracked heat exchanger, or a refrigerant leak before it turns into an emergency.
You won't find us buried under layers of call-center scripts — we're the company that tells you what actually needs fixing instead of what pads the ticket. We carry the credentials Mount Prospect inspectors and property managers expect to see, and we keep that documentation available on request for every job, big or small.
Being local matters more than most companies let on. 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.
Too many homeowners in Mount Prospect have a story about a tech who showed up late, quoted one price, and charged another. 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 Mount Prospect 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 Mount Prospect properties actually need.
Breakdowns rarely happen at a convenient time, which is exactly why our emergency line runs 24 hours a day. Our Mount Prospect dispatch team prioritizes no-heat and no-cooling calls so a technician is diagnosing your system as fast as physically possible.
If a specialty part genuinely does need to be ordered, we'll set up a safe temporary fix and give you a real timeline instead of leaving you guessing.
An aging system that's constantly breaking down usually costs more to keep patching than to replace. We walk Mount Prospect homeowners through financing and rebate options where available before a single piece of equipment gets ordered.
Most installs in Mount Prospect are completed in a single day, and we walk you through the new thermostat and any app controls before we leave.
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 rooftop units and package systems across Mount Prospect, with priority response for facilities that can't afford downtime.
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 humidifier, dehumidifier, and air purifier installation for Mount Prospect 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.
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.
If anything feels off after we leave, one call gets a tech back to your Mount Prospect address.
A little attention to how your system is running can save you a lot of money and discomfort.
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 Mount Prospect.
Gradual efficiency loss is easy to miss month to month, but it adds up fast over a season.
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.
We'll always tell you honestly when a repair is the better call versus when it isn't.
You'll know the cost before a wrench touches your system.
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.
Every technician carries current state licensing and manufacturer training.
We explain what failed, why it failed, and what the options are.
Replacement systems don't have to be paid in one lump sum.
A snapshot of the feedback that keeps us accountable.
"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."
"We've used them for our maintenance plan for two years now and never had a surprise breakdown. 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. 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. Documentation for our records was thorough and easy to file."
"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. This is the company I'm saving in my phone now."
After thousands of service calls across Mount Prospect, a handful of causes show up again and again.
Mount Prospect'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.
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 Mount Prospect 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.
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.
Experienced with the light industrial and retail equipment common across the area.
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.
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.
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.
We cover Mount Prospect and the surrounding communities, including the zip codes listed in our coverage section below.
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.
Twice-yearly maintenance is the standard we recommend given the temperature swings the area sees.
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.
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 Mount Prospect — older homes often still run original ductwork that needs different care than the sealed, high-efficiency systems going into newer builds.
We also work regularly with homeowners associations, property management companies, and multi-unit buildings throughout Mount Prospect.
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 Mount Prospect 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 Mount Prospect, IL and near Mount Prospect, there's a strong chance we already service your street.
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.
