No overselling, no guesswork — just a Furnace Repair crew that diagnoses it right the first time. Same-day appointments available across Deerfield and the surrounding zip codes.

Our Deerfield dispatcher asks a few quick questions to gauge urgency and get you the fastest available window.
You'll get a flat-rate quote before any repair work begins — no guessing what the final bill will look like.
Warranty details are explained clearly so you know exactly what's covered going forward.
Leonard HVAC was built by technicians who got tired of watching homeowners get oversold. 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 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 Deerfield inspectors and property managers expect to see, and we keep that documentation available on request for every job, big or small.
Deerfield'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.
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'd rather lose a job to a lower bid than win one by cutting corners on the diagnosis, because a customer who trusts us once tends to call us again — and Deerfield is a small enough community that reputation travels fast.
When you call +1-866-805-8548, you're talking to someone who understands the local permitting process, the common equipment brands installed in Deerfield homes, and realistic scheduling given local demand. 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 Furnace Repair system fails without warning, waiting days for an appointment isn't an option. Our Deerfield dispatch team sends the closest available truck first 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 Deerfield homeowners through load calculations so the new system is sized correctly for the actual square footage before a single piece of equipment gets ordered.
Most installs in Deerfield 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 Deerfield, with after-hours work to avoid disrupting business.
Our commercial techs are trained to work around your customers and staff, scheduling noisy or disruptive work outside peak hours whenever possible.

Most emergency breakdowns start as a small, ignorable warning sign months earlier. Beyond standard tune-ups, we also handle humidifier, dehumidifier, and air purifier installation for Deerfield households that want more than just temperature control.
Maintenance plan members in Deerfield 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.
Details vary by job type and are always shared upfront, never buried in fine print.
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.
A little attention to how your system is running can save you a lot of money and discomfort.
A healthy system runs with a consistent, low hum — banging, screeching, or grinding usually points to a loose part or failing motor.
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.
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.
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.
Emergency calls get moved to the front of the line automatically.
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.
We explain what failed, why it failed, and what the options are.
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."
"Scheduled a fall tune-up and they caught a cracked part before it became a real problem. 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. Would recommend to anyone in Deerfield 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. 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. No overnight surcharge shock — the price matched what dispatch quoted me on the phone."
None of these are unusual or embarrassing — they're just the normal wear and tear that comes with running a system through Deerfield's seasonal swings.
Deerfield's seasonal swings put real stress on a system that isn't maintained regularly. 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.
Keeping vents unblocked by furniture and rugs helps maintain even airflow throughout the home. 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 Deerfield 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.
We don't outsource dispatch to a call center that's never met our technicians.

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

Known for fast, accurate diagnostics on no-heat and no-cool breakdowns.

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.
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.
Every technician we send is licensed in accordance with Deerfield, WI requirements and carries full liability coverage.
As a general guideline, if a system is past 12-15 years old and facing a costly repair, replacement often makes more financial sense.
Ask your technician about current plan pricing during any service call.
We cover Deerfield 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.
Financing options are available for qualifying replacement installations, and our team can walk you through what's currently offered.
Most Deerfield homes benefit from two tune-ups a year — one before cooling season and one before heating season.
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.
Most standard repairs are completed in under two hours once the technician has diagnosed the issue and you've approved the quote.
For most residential visits, yes, an adult should be present to grant access and approve any quoted work.
Our technicians are familiar with both, which means less time spent figuring out your specific setup and more time actually fixing the problem.
If you manage several units or a shared system across a Deerfield property, ask about setting up a standing service account so every request gets handled under one consistent agreement.
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 Deerfield 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 Deerfield, WI and near Deerfield, 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.