Your Trusted Heating & AC Repair Experts in Amherst, NH
Since 1987, GSMS has been proud to offer top-notch HVAC services to residents of Amherst, NH. With over three decades of experience, our family-owned business has built a reputation for excellence, reliability, and outstanding customer service. We provide a comprehensive range of HVAC services, including air conditioning repair, replacement, and maintenance, as well as heating services for furnaces and boilers.
Get the Best HVAC Service in Amherst
Whether you need a quick repair, a complete system installation, or regular maintenance, our team is dedicated to providing personalized service tailored to your specific requirements.
Don’t let HVAC issues disrupt your comfort—call GSMS today at 603-424-8258 to schedule your heating and cooling service in Amherst, NH, and experience the difference of working with trusted local professionals.
- Furnace Repair: Is your furnace blowing cold air or refusing to turn on? Our certified techs are trained to service all major brands. We’ll get your heat back fast.
- New Furnace Installation: Upgrading your heating system? We install energy-efficient gas furnaces, electric furnaces, and hybrid systems designed for winters.
- Heat Pump Repair: Troubleshoot and repair heat pumps for both heating and cooling issues, including compressor failure and refrigerant leaks.
- Heat Pump Installation & Replacement: Looking to upgrade to an energy-efficient heat pump? We’ll help you choose the right system and install it with precision.
- HVAC Maintenance & Tune-Ups: Annual maintenance keeps your system running efficiently and avoids unexpected breakdowns. Our furnace tune-up service includes inspection, cleaning, and performance checks. Prevent breakdowns and high energy bills with seasonal AC maintenance. We clean coils, check refrigerant levels, and test performance.
- AC Repair Service: If your air conditioner isn’t cooling, is leaking, or making loud noises, don’t wait. We handle repairs quickly and professionally.
- Air Conditioning Installation: Need a new system? We replace central AC systems and high-efficiency cooling units sized for your home and budget.
- Ductless Mini-Spilt Systems: Our expert technicians are also skilled in installing and maintaining ductless mini-splits, ensuring that your home stays comfortable year-round. At GSMS, we use only the highest quality products from leading manufacturers, guaranteeing efficient and long-lasting solutions for your HVAC needs.
- Indoor Air Quality Solutions: Dust, allergens, and humidity making life uncomfortable? We install whole-home air purifiers, dehumidifiers, and advanced filtration systems.
- Duct Cleaning Services: Clogged air ducts can reduce airflow and raise energy bills. Our air duct cleaning improves HVAC efficiency and air quality.
- Humidity Control: From humidifiers to dehumidifiers, we help you balance indoor moisture for health, comfort, and HVAC performance.
Expert Plumbers Serving Amherst
In addition to our heating and air conditioning services, we offer top-quality plumbing services to the residents of Amherst, NH. With over three decades of experience, our family-owned business has established a reputation for trust, reliability, and exceptional customer care.
- Water heater repair, replacement, and maintenance for both tank and tankless models.
- Kitchen plumbing: From faucet and sink installations to dishwasher and water line services. In the bathroom, our expert plumbers handle everything from toilet and shower repairs to vanity plumbing and pipe replacement.
At GSMS, we use only the highest quality materials and the latest techniques to provide efficient and long-lasting solutions for your plumbing needs. Whether you require a quick repair, a complete installation, or regular maintenance, our team is committed to delivering personalized service tailored to your home’s unique requirements.
Don’t let plumbing issues disrupt your daily routine—call GSMS today at 603-424-8258 to schedule your plumbing service in Amherst, NH, and experience the peace of mind that comes with working with trusted local professionals.
Recent Jobs and Reviews in Amherst, NH
Amherst, NH at a glance
GSMS Air•Heating•Plumbing has completed 25 jobs in Amherst, NH between June 2026 and October 2026.
The 12 customer reviews shown here average 5.0 out of 5.
The most recent job was on October 21, 2026.
GSMS Air•Heating•Plumbing has completed 52 jobs in Amherst, NH in the last 12 months. The first job there was in August 2024.
Our Local Reviews by City
- Amherst, NH (12)
- Atkinson, NH (2)
- Auburn, NH (3)
- Barrington, NH (24)
- Bedford, NH (41)
- Bow, NH (3)
- Candia, NH (3)
- Chester, NH (2)
- Concord, NH (11)
- Deerfield, NH (1)
- Derry, NH (3)
- Dover, NH (1)
- Durham, NH (2)
- Epping, NH (4)
- Exeter, NH (2)
- Gilford, NH (1)
- Gilmanton, NH (4)
- Goffstown, NH (10)
- Greenland, NH (3)
- Hampstead, NH (2)
- Hampton, NH (3)
- Henniker, NH (3)
- Hillsborough, NH (1)
- Hollis, NH (20)
- Hooksett, NH (21)
- Hudson, NH (8)
- Lee, NH (2)
- Litchfield, NH (3)
- Londonderry, NH (17)
- Madbury, NH (1)
- Manchester, NH (78)
- Merrimack, NH (71)
- Milford, NH (9)
- Moultonborough, NH (2)
- Nashua, NH (72)
- New Boston, NH (4)
- Newbury, NH (1)
- Newmarket, NH (3)
- Northfield, NH (2)
- Northwood, NH (2)
- Pembroke, NH (1)
- Raymond, NH (1)
- Rochester, NH (2)
- Salem, NH (4)
- Sandown, NH (3)
- Strafford, NH (1)
- Stratham, NH (15)
- Tilton, NH (1)
- Weare, NH (8)
- Windham, NH (11)
- York, ME (2)
Job Locations and Reviews
Mark D.
Oil furnace pm and replace first floor thermostat
Amherst, NH 03031
Jack D.
Onstall Lennox S40 thermostat. Perform furnace maintenance. I reccomend installing gas low pressure switch and replacing the inducer vent coupling.
Amherst, NH 03031
Jack D.
Look at ductwork in basement in regards to no air flow out of cieling supply grille. I found that the previous homeowner had taken the duct and connected it to the pellet furnace.
Amherst, NH 03031
Jack D.
Furnace PM.
Amherst, NH 03031
Review
Showed up when scheduled and did a thorough inspection with diagnosis of two components in our furnace which would cause trouble down the road.
Jack D.
Furnace PM. Reccomend replacing combustion motor and flame rod.
Amherst, NH 03031
Adam P.
Following our recent service visit where we discovered high carbon monoxide (CO) readings and had to red-tag your 31-year-old furnace, this proposal outlines the complete modernization of your home's heating and cooling infrastructure. The Hybrid Strategy (Dual-Fuel): We know your primary goal is to be energy-conscious and electrify your home as much as possible. However, based on our load calculations, an electric heat pump alone will not have the capacity to keep up with your home's heat loss on the coldest winter days. To give you the best of both worlds, we have designed a Lennox Hybrid System. This system pairs the top-tier Lennox SLP99 Modulating Gas Furnace with the ultra-efficient Lennox EL21KLV Cold-Climate Heat Pump. The system uses your "Thermal Balance Point" to maximize efficiency: during milder winter weather, it uses the highly efficient electric heat pump. The moment the temperature drops to the point where the heat pump can no longer keep up, the system's "brain" aut
Amherst, NH 03031
Review
Excellent service and very knowledgeable technician.
Mark D.
Remove toilet and reset
Amherst, NH 03031
Qwentin G.
Completed the oil boiler maintenance today. Everything went great. Please see the attached form. I also replaced the air vent that had failed.
Amherst, NH 03031
Jack D.
Rinnai no HW. Found inlet screen completely plugged. Still producing lukewarm water so I completed a flush on the HX. Hot water back on. Thank you! I reccomend testing water and adding a sediment filter to your home water. This was very premature for the system to be blocked up.
Amherst, NH 03031
Mark D.
Installed taco leak shut off
Amherst, NH 03031
Qwentin G.
I found that the cold water flexible line was leaking. I recommended installing a leak stop valve and hard piping in the cold water inlet.
Amherst, NH 03031
Jack D.
Trouble shoot HW recirculation line that is pushing HW into CW pipes. We narrowed it down to shower valve upstairs. I also replaced the comdensate pump that wasn't working. Thank you!
Amherst, NH 03031
Jack D.
Well Water test Comprehensive + radon.
Amherst, NH 03031
Mark D.
This proposal outlines the replacement of your failed 40-gallon Bradford White power-vented natural gas water heater. Because your tank is currently covered under the manufacturer's warranty, the physical cost of the new tank itself is covered. The pricing in this proposal strictly covers the professional labor, the distributor's warranty processing fee, the necessary structural plumbing modifications, and the required safety code upgrades to properly install the new unit. Scope of Work 1. Demolition & Warranty Processing Removal: We will safely drain, disconnect, and remove your existing failed water heater. Warranty Handling: GSMS will handle the logistics of returning the failed tank and will cover the $100 warranty processing fee charged by the distributor on your behalf. 2. Equipment Installation & Code Upgrades The New Tank: We will supply and install your new warranty-replacement 40-gallon Bradford White power-vented natural gas water heater in the exact same footprint. Conn
Amherst, NH 03031
Jack D.
Today I assessed the existing water treatment system. Also, I took a comprehensive + radon water test. Once we receive the results from the laboratory, we will report back to you with the results.
Amherst, NH 03031
Qwentin G.
Completed the AC maintenance today. Everything went great. Please see the attached form.
Amherst, NH 03031
Qwentin G.
Replaced the Lennox TXV valve under warranty. Client paid for labor and new refrigerant. Checked operating pressures and the unit was running perfect. Unit is in perfect operating condition now.
Amherst, NH 03031
Mark D.
Replaced shower arm
Amherst, NH 03031
Mark D.
Install new toilet
Amherst, NH 03031
Mark D.
Install check valves on hot and cold outside faucet
Amherst, NH 03031
Qwentin G.
Found that the TXV valve is acting up. Either the screen inside is plugged up or there's an issue with the valve itself. The part is covered under warranty but the labor is not. We will send over the estimate to replace the TXV valve in the next couple of days.
Amherst, NH 03031
Qwentin G.
Completed the AC maintenance today. Everything went great! Please see the attached form.
Amherst, NH 03031
Qwentin G.
Completed the AC maintenance today. Everything went great. Please see the attached form.
Amherst, NH 03031
Mark D.
Replaced outside faucet,Did est for toilet replacement
Amherst, NH 03031
Mark D.
remove pressure switch sensor from combustion blower clear blockage applied RTV and reinstalled. System running fine.
Amherst, NH 03031
Review
No heat emergency situation handled immediately on a Sunday evening. Great service!
Review
Courteous professional excellent service!
Review
Professional service. These guys are the best. Trusted service provider!
Review
A pleasure to deal with
Review
Jack is always polite and friendly and willing to answer any questions we might have.
Review
Jack is the best of the best
Review
I couldn’t ask for more. In fact I signed up for a regular maintenance program with him
Response from GSMS Air•Heating•Plumbing:
We count ourselves lucky for customers like you and look forward to working with you again in the future!
Review
First time, here.Wonderful guys, great work. See them, next year!
Review
Great
Review
We have used GSMS for years and have always been very pleased with their service!
Response from GSMS Air•Heating•Plumbing:
Love to hear it, Maria!! Thank you for taking the time to shout out our awesome team.
