Our Londonderry-based crews carry the parts and the know-how to get your air moving again today. Same-day appointments available across Londonderry and the surrounding zip codes.

No automated menus for emergencies — a real person handles the call.
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 grew one honest service call at a time in communities like Londonderry. Every technician we send to your door is background-checked, factory-trained, and licensed to work on the systems installed throughout Londonderry, NH.
We're not the biggest name in Londonderry — we're the team that shows up in the truck, not a subcontractor we've never met. 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.
Londonderry'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 Londonderry 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. 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 Londonderry 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.
Whether it's a mid-summer breakdown or a planned system replacement, our Londonderry techs handle it with the same level of care.
Breakdowns rarely happen at a convenient time, which is exactly why our emergency line runs 24 hours a day. Our Londonderry 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.

Not every repair call ends in a repair — sometimes the honest recommendation is a properly sized replacement. We walk Londonderry homeowners through financing and rebate options where available before a single piece of equipment gets ordered.
Most installs in Londonderry 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 multi-zone commercial buildouts across Londonderry, 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.

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 duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces for Londonderry 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 Londonderry technician on our team is held to.
Details vary by job type and are always shared upfront, never buried in fine print.
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 Londonderry address.
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.
This is one of the most common complaints we hear on service calls across Londonderry.
A tune-up often identifies exactly what's driving the extra energy use.
A system that won't hold a steady cycle is often fighting a sizing issue, a thermostat problem, or a refrigerant imbalance.
A musty smell often points to mold or moisture buildup somewhere in the ductwork.
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.
Emergency calls get moved to the front of the line automatically.
We don't consider a job finished until the system is actually performing correctly.
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.
We'll walk you through what's actually available before you decide.
A snapshot of the feedback that keeps us accountable.
"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."
"Signed up for the annual plan after our first repair and it's paid for itself already. 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 Londonderry needing a real replacement, not a patch job."
"Commercial dispatch was quick and the tech understood our system without needing to be walked through it. 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. 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 Londonderry's seasonal swings.
Homeowners who schedule a tune-up ahead of each season tend to call us far less often for emergency repairs. 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.
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 Londonderry 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 Londonderry installs and specializes in properly sizing equipment for older housing stock.

Runs point on overnight and weekend emergency calls throughout Londonderry.

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.
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.
Every technician we send is licensed in accordance with Londonderry, NH 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.
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.
Our technicians are trained across the major residential and commercial equipment lines, not limited to a single manufacturer.
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.
Beyond basic safety checks, it's best to leave diagnosis to a licensed technician rather than attempting a repair yourself.
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.
From the older, established streets near the center of Londonderry to the newer developments on the outskirts, our trucks cover the full footprint of the city.
If you manage several units or a shared system across a Londonderry property, ask about setting up a standing service account so every request gets handled under one consistent agreement.
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 Londonderry 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 Londonderry, NH and near Londonderry, there's a strong chance we already service your street.
Property managers with multiple Londonderry addresses can consolidate everything under one account for simpler scheduling and consistent pricing across every location.