Our Mount Prospect-based crews carry the parts and the know-how to get your air moving again today. 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.
If anything feels off after we leave, a follow-up call gets a technician back out to make it right.
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, big or small.
Mount Prospect's climate swings hard, and generic national playbooks don't always fit. 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. 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 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. Our warranty and service history records stay attached to your address, so any future technician who visits already has the full picture.
Every service below is backed by the same licensing, warranty, and upfront pricing you get on any job we run.
When your Hvac 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 load calculations so the new system is sized correctly for the actual square footage 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 Mount Prospect, with service agreements built around your operating hours.
We understand that a commercial call isn't just about comfort, it's about keeping a business open.

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 indoor air quality upgrades for homes with allergy or asthma concerns 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.

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.
If anything feels off after we leave, one call gets a tech back to your Mount Prospect address.
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 Mount Prospect.
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 musty smell often points to mold or moisture buildup somewhere in the ductwork.
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.
Because our trucks are stationed near Mount Prospect, we're rarely far from your address.
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.
Photos and plain-language notes accompany every diagnostic.
Maintenance plan members get priority scheduling and discounted rates.
We don't write these — our customers do.
"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. 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. Would recommend to anyone in Mount Prospect needing a real replacement, not a patch job."
"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."
"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 Mount Prospect's seasonal swings.
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.
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 Mount Prospect 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 Mount Prospect roster goes through background checks, licensing verification, and ongoing manufacturer training.

Handles the majority of Mount Prospect installs and specializes in properly sizing equipment for older housing stock.

Keeps the emergency truck stocked based on what actually fails most often locally.

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.
We explain the diagnostic fee upfront and provide a flat-rate repair quote once the issue is identified.
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.
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.
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.
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.
Check that the thermostat has power and the batteries aren't dead, and check your breaker panel for a tripped switch before calling.
We'd rather quote it honestly on the phone than have you feel ambushed by the bill.
Straightforward fixes like a capacitor swap or a thermostat replacement are often finished in well under an hour.
For commercial accounts or rental properties, a designated point of contact or property manager can coordinate access instead.
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.
We accept standard payment methods for repairs and smaller jobs, and we'll always tell you upfront what a given service is likely to cost so there's no last-minute scramble to figure out payment. 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.