No overselling, no guesswork — just a Emergency Hvac crew that diagnoses it right the first time. Same-day appointments available across Mount Prospect 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.
A licensed technician arrives, runs a full diagnostic, and explains exactly what's wrong in plain language.
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.
We're not the biggest name in Mount Prospect — 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.
We know which neighborhoods run on older ductwork and which subdivisions were built with newer high-efficiency systems. That local knowledge shapes the parts we stock on the truck — 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 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.
Every service below is backed by the same licensing, warranty, and upfront pricing you get on any job we run.
Breakdowns rarely happen at a convenient time, which is exactly why our emergency line runs 24 hours a day. 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.
Not every repair call ends in a repair — sometimes the honest recommendation is a properly sized replacement. We walk Mount Prospect homeowners through financing and rebate options where available before a single piece of equipment gets ordered.
Every install ends with a performance test, confirming airflow, temperature split, and refrigerant charge are all where they should be before we consider the job finished.
Downtime in a commercial space costs money every hour a system is offline. Our commercial division services rooftop units and package systems across Mount Prospect, with priority response for facilities that can't afford downtime.
We understand that a commercial call isn't just about comfort, it's about keeping a business open.
Most emergency breakdowns start as a small, ignorable warning sign months earlier. Beyond standard tune-ups, we also handle duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces for Mount Prospect households that want more than just temperature control.
Maintenance plan members in Mount Prospect get scheduling reminders automatically, so tune-ups don't fall through the cracks during a busy season.
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.
Emergency dispatch never comes with a hidden surcharge sprung on you after the fact.
A technician doesn't consider the job done until the system is tested and performing correctly.
Catching these signs early usually means a same-day repair instead of an emergency call at the worst possible moment.
Rattling during startup often means a component has worked itself loose and needs tightening before it causes real damage.
Weak airflow from the vents often traces back to a clogged filter, a failing blower motor, or leaking ductwork.
Gradual efficiency loss is easy to miss month to month, but it adds up fast over a season.
Short cycling puts extra wear on the compressor and shortens the system's overall lifespan.
A musty smell often points to mold or moisture buildup somewhere in the ductwork.
Repeated repairs on an aging system are usually the clearest sign that replacement will save more money than another patch job.
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.
If something isn't right after we leave, we come back and make it right.
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.
"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. 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. New system is noticeably quieter and our energy bill actually dropped."
"As a property manager, having a company that actually answers after-hours calls is rare. Now our go-to for every property in the portfolio."
"I appreciated that they didn't try to sell me a bigger unit than I needed. My energy bill dropped noticeably the first month with the new system."
"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.
Mount Prospect's seasonal swings put real stress on a system that isn't maintained regularly. Filters should be checked monthly during heavy-use seasons and replaced roughly every 60-90 days depending on your household and any pets.
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.
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.
Here's a look at the kind of experience that shows up at your door.
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.
Works directly with Mount Prospect property managers to schedule around business hours.
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.
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.
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 commercial accounts or rental properties, a designated point of contact or property manager can coordinate access instead.
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.
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 Mount Prospect installation, our technicians will flag it during the estimate rather than leaving you to track it down after the fact.
We dispatch throughout Mount Prospect and the neighboring communities, keeping response times tight because our trucks stay close to home.
Property managers with multiple Mount Prospect addresses can consolidate everything under one account for simpler scheduling and consistent pricing across every location.
