No overselling, no guesswork — just a Hvac Installation crew that diagnoses it right the first time. Same-day appointments available across Mount Prospect and the surrounding zip codes.

Our Mount Prospect 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.
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 Mount Prospect. Our crews carry manufacturer certifications across the major residential and commercial equipment lines.
We're not interested in being the cheapest quote on the page — we're the crew that answers the phone at 2am when your furnace quits in the middle of a cold snap. Licensing and insurance aren't optional line items for us, and we keep that documentation available on request for every job, residential or commercial.
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.
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 Mount Prospect is a small enough community that reputation travels fast.
Our office team is based locally too, not routed through an out-of-state call center that's never seen a Mount Prospect rooftop unit. It also means faster escalation when something's urgent — a local dispatcher can reroute the nearest truck in minutes, not hours.
We cover the full range of heating, cooling, and air quality work Mount Prospect properties actually need.
When your Hvac Installation system fails without warning, waiting days for an appointment isn't an option. Our Mount Prospect dispatch team moves emergency tickets to the front of the schedule 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.

If your unit is past its expected service life, running loud, or spiking your utility bill, a replacement conversation is worth having. We walk Mount Prospect 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.

A retail floor, a restaurant kitchen, or an office suite can't run without stable climate control. Our commercial division services multi-zone commercial buildouts across Mount Prospect, 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.

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 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.
A technician doesn't consider the job done until the system is tested and performing correctly.
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.
Gradual efficiency loss is easy to miss month to month, but it adds up fast over a season.
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.
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.
Parts and labor are backed by warranty terms explained in plain language.
We run background checks because you're letting someone into your home.
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.
"The furnace stopped working overnight and someone was at our door before 9am. 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. You can tell these guys actually know what they're doing."
"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."
"As a property manager, having a company that actually answers after-hours calls is rare. Documentation for our records was thorough and easy to file."
"The estimate matched the final invoice exactly, down to the dollar. Would use them again without hesitation."
"Diagnosed a failed capacitor and had it swapped within the hour. This is the company I'm saving in my phone now."
None of these are unusual or embarrassing — they're just the normal wear and tear that comes with running a system through Mount Prospect's seasonal swings.
The shift between peak heating and peak cooling demand is exactly when older or neglected equipment tends to fail. Before the heaviest cooling months hit, it's worth having the refrigerant charge checked, the condenser coils cleaned, and the filter replaced — all of which directly affect how hard the compressor has to work.
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.
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.

Runs point on overnight and weekend emergency calls throughout Mount Prospect.

Focuses on commercial rooftop units, multi-zone systems, and facility maintenance contracts.
Standard appointments are usually scheduled within 24-48 hours, while true emergencies jump the queue.
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.
Yes — licensing and insurance documentation is available on request for any job, residential or commercial.
We never push a replacement when a straightforward repair will genuinely solve the problem.
Plan members typically see fewer surprise breakdowns because small issues get caught during routine visits.
Our dispatch area extends throughout the greater Mount Prospect region and nearby towns within Mount Prospect, IL.
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.
Beyond basic safety checks, it's best to leave diagnosis to a licensed technician rather than attempting a repair yourself.
Ask about current after-hours rates when you call +1-866-805-8548.
Straightforward fixes like a capacitor swap or a thermostat replacement are often finished in well under an hour.
For most residential visits, yes, an adult should be present to grant access and approve any quoted work.
From the older, established streets near the center of Mount Prospect to the newer developments on the outskirts, our trucks cover the full footprint of the city.
Larger properties get the same upfront pricing and licensed technicians as a single-family service call, just coordinated at scale.
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.
Coverage extends across Mount Prospect proper and into the nearby zip codes listed below.
Coverage isn't limited to a single neighborhood or subdivision — our Mount Prospect dispatch zone stretches across the metro area and into the surrounding suburbs and unincorporated communities.