We fix what's broken, fast, and we don't disappear after the invoice. Same-day appointments available across Merrimack 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.
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 didn't start as a franchise chasing volume. 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. Every job we run is backed by full liability coverage and current state licensing, 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 Merrimack 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 Merrimack rooftop unit. Our warranty and service history records stay attached to your address, so any future technician who visits already has the full picture.
We cover the full range of heating, cooling, and air quality work Merrimack properties actually need.
A dead system in the middle of a heat wave or a cold snap isn't just inconvenient — it can be a real safety issue for kids, pets, and older residents. Our Merrimack dispatch team prioritizes no-heat and no-cooling calls so a technician is diagnosing your system as fast as physically possible.
Once a technician is on-site, the goal is always a same-visit repair — most emergency calls in Merrimack get resolved in a single trip, not a multi-day back-and-forth.

If your unit is past its expected service life, running loud, or spiking your utility bill, a replacement conversation is worth having. We walk Merrimack 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 light industrial and warehouse ventilation across Merrimack, with after-hours work to avoid disrupting business.
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 humidifier, dehumidifier, and air purifier installation for Merrimack 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.

This is the standard every Merrimack technician on our team is held to.
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.
If anything feels off after we leave, one call gets a tech back to your Merrimack address.
Most breakdowns don't happen without warning — they announce themselves for weeks before the system actually quits.
A healthy system runs with a consistent, low hum — banging, screeching, or grinding usually points to a loose part or failing motor.
If some rooms stay hot or cold no matter what the thermostat says, the system may be struggling to distribute air evenly.
A tune-up often identifies exactly what's driving the extra energy use.
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.
If you're calling about the same problem every few months, the underlying cause likely hasn't been fully addressed.
We explain diagnostic fees and repair estimates before authorizing work.
Because our trucks are stationed near Merrimack, 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.
"Our AC quit on the hottest weekend of the year and they had a tech out within a couple of hours. Fixed on the first visit and explained everything in terms I could actually understand."
"Scheduled a fall tune-up and they caught a cracked part before it became a real problem. Techs are always polite, always on time, and clean up after themselves."
"Had a full system replacement done and it was the smoothest home project I've had in years. Would recommend to anyone in Merrimack needing a real replacement, not a patch job."
"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."
"I appreciated that they didn't try to sell me a bigger unit than I needed. Installation crew was in and out in a day and left the space cleaner than they found it."
"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."
Understanding what typically fails helps homeowners know what to watch for and when a repair call is worth making before things get worse.
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.
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 Merrimack 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.

Over a decade in residential heating and cooling, with a focus on load calculations and full system replacements.

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

Experienced with the light industrial and retail equipment common across the area.
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.
Yes — every job gets a clear quote before any repair work begins, so there are no surprise line items on the invoice.
Our emergency line runs 24 hours a day, including nights, weekends, and holidays.
Every technician we send is licensed in accordance with Merrimack, NH requirements and carries full liability coverage.
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.
We cover Merrimack and the surrounding communities, including the zip codes listed in our coverage section below.
Yes, we run separate residential and commercial divisions, both fully licensed and equipped for their respective equipment.
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.
Most Merrimack homes benefit from two tune-ups a year — one before cooling season and one before heating season.
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.
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.
Our technicians are familiar with both, which means less time spent figuring out your specific setup and more time actually fixing the problem.
We also work regularly with homeowners associations, property management companies, and multi-unit buildings throughout Merrimack.
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 Merrimack 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 Merrimack, NH and near Merrimack, 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.