No overselling, no guesswork — just a Hvac Maintenance crew that diagnoses it right the first time. Emergency dispatch available across Mount Prospect and the surrounding zip codes.
No automated menus for emergencies — a real person handles the call.
A licensed technician arrives, runs a full diagnostic, and explains exactly what's wrong in plain language.
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 interested in being the cheapest quote on the page — 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, residential or commercial.
Mount Prospect's climate swings hard, and generic national playbooks don't always fit. 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.
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.
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.
We keep the truck stocked with the parts that fail most often on the equipment common to Mount Prospect 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 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.
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 indoor air quality upgrades for homes with allergy or asthma concerns 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.
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.
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.
A healthy system runs with a consistent, low hum — banging, screeching, or grinding usually points to a loose part or failing motor.
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.
Short cycling puts extra wear on the compressor and shortens the system's overall lifespan.
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.
No inflated "emergency surcharge" games — the number we quote is the number you pay.
Because our trucks are stationed near Mount Prospect, we're rarely far from your address.
Parts and labor are backed by warranty terms explained in plain language.
Our techs recognize brand-specific quirks instead of learning your system on the job.
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.
A snapshot of the feedback that keeps us accountable.
"The furnace stopped working overnight and someone was at our door before 9am. 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. Would recommend to anyone in Mount Prospect needing a real replacement, not a patch job."
"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."
"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."
"Diagnosed a failed capacitor and had it swapped within the hour. 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.
The shift between peak heating and peak cooling demand is exactly when older or neglected equipment tends to fail. 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.
Our technicians train across the major residential and commercial equipment lines, so you're not limited to a single brand's service network. 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.
Over a decade in residential heating and cooling, with a focus on load calculations and full system replacements.
Keeps the emergency truck stocked based on what actually fails most often locally.
Experienced with the light industrial and retail equipment common across the area.
Standard appointments are usually scheduled within 24-48 hours, while true emergencies jump the queue.
We explain the diagnostic fee upfront and provide a flat-rate repair quote once the issue is identified.
Our emergency line runs 24 hours a day, including nights, weekends, and holidays.
Every technician we send is licensed in accordance with Mount Prospect, IL requirements and carries full liability coverage.
We never push a replacement when a straightforward repair will genuinely solve the problem.
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.
Our commercial team handles rooftop units, multi-zone systems, and facility contracts alongside our standard residential repair work.
Yes, we service systems regardless of who originally installed them.
Ask about financing during your in-home estimate to see what fits your situation.
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.
Our pricing is explained clearly before dispatch, and any after-hours consideration is communicated upfront — never as a surprise on the final invoice.
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.
Let dispatch know ahead of time if access will be handled differently than a standard homeowner visit.
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.
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.
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.
