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Our Service Area

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Proudly Serving New Hampshire Homeowners

At GSMS, we are proud to serve New Hampshire with our comprehensive range of HVAC and plumbing services.

As a family-owned business with 35+ years of experience, we have built a reputation for excellence, reliability, and outstanding customer care. Our skilled technicians are dedicated to providing top-quality repairs, installations, and maintenance tailored to meet the unique needs of New Hampshire homeowners.

Explore our service area below, read reviews in your city, and see why homeowners across New Hampshire trust GSMS for their HVAC and plumbing needs.

Contact us online today or call 603-424-8258 to schedule your service and experience the GSMS difference.

Recent Jobs and Reviews

Rated 5.0 out of 5 stars based on 397 customer reviews

Customers say: The recent reviews exhibit a predominantly positive sentiment, with recurring themes of satisfaction, professionalism, and expertise. Customers express gratitude, recommend the company, and acknowledge the quality of the work performed. Positive reviews frequently mention friendly and knowledgeable technicians, timely responses, and efficient service. Negative reviews are minimal and do not represent a clear, recurring trend. Overall, the reviews suggest a positive experience with the company, with many customers expressing satisfaction with their HVAC and plumbing needs.

Job Locations and Reviews

Jack D.
Jack D. Checked in
Minisplit PM GSMS HomeClub Premier
Epping, NH 03042
Mark D.
Mark D. Checked in
Unit locked out.Reset unit,unit came on but making noise from condensing fan motor.Motor vibrating and not coming up to speed.
Bedford, NH 03110
Review
Excellent service
Lisa - Exeter, NH 03833
Qwentin G.
Qwentin G. Checked in
Completed the mini split maintenance today. Everything went great! Please see the attached form.
Exeter, NH 03833
Mark D.
Mark D. Checked in
Replaced 22 valves and pm on rinnai and a/c
Merrimack, NH 03054
Qwentin G.
Qwentin G. Checked in
Completed the AC maintenance today. Everything went great. Please see the attached form.
Pelham, NH 03076
Qwentin G.
Qwentin G. Checked in
Completed the AC maintenance today. Everything went great. Please see the attached form.
Manchester, NH 03104
Qwentin G.
Qwentin G. Checked in
Completed the AC maintenance today. Everything went great! Please see the attached form.
Merrimack, NH 03054
Jack D.
Jack D. Checked in
New system AC startup.
Hooksett, NH 03106
Qwentin G.
Qwentin G. Checked in
Completed the AC maintenances today. Everything went great! Please see the attached form.
Amherst, NH 03031
Qwentin G.
Qwentin G. Checked in
Completed both AC maintenances today. Everything went great! Please see the attached form.
Amherst, NH 03031
Review
He arrived on time and was neat and orderly and very pleasant to deal with.
Grantly - Bow, NH 03304
Review
Respectful and knows what he is talking about. Even dealt with Stanley in a way they are always welcome back. If i could give more than 5 stars i would.
Holly - Northwood, NH 03261
Review
Very pleased with Qwentin
Bonnie - Bedford, NH 03110
Review
Qwentin was on-time. Friendly, polite, and conscientious. All work was performed and verified. Would recommend to anyone looking for HVAC service or installation.
Thomas - Merrimack, NH 03054
Review
Great service, nice app to track when service tech will arrive. Answered all questions pleasant to talk with and very conscientious.
John L - Bedford, NH 03110
Review
Qwentin was his professional and friendly self today. I am always very happy with his work.
Barry Fitzgerald - Manchester, NH 03109
Review
Glad to see the ole man still working!! LOL
Phil - Windham, NH 03087
Review
Friendly, efficient service
Charlie - Concord, NH 03301
Review
Excellent and very prompt.. Thank you
Mike - Hampton, NH 03842
Review
Love dealing with this company. Their techs are always prompt, efficient and courteous. We've been happy to be their customer since 2010.
Skip Sagris - Bow, NH 03304
Response from GSMS Air•Heating•Plumbing:

Thank you so much for the kind words and for being part of the GSMS family since 2010! It means the world to us to have earned your trust over the years. I’m proud of our team for continuing to deliver the kind of service that keeps clients like you coming back. We truly appreciate your loyalty and support. – Zak D., Second-Generation Owner

Review
Qwentin was on time, very friendly and professional. He was able to identify the issue, communicate it effectively, and then fix it. Highly recommend.
Phil Cutler - Bedford, NH 03110
Response from GSMS Air•Heating•Plumbing:

Thank you so much for the kind words and for trusting GSMS to take care of your home. Qwentin is a rising star on our team, and it means a lot to hear that his professionalism and communication made a strong impression. As a local, family-run business, we’re grateful for your recommendation and honored to have earned your trust. – Zak D., Second-Generation Owner

Review
Great service again. On time and professional. I highly recommend GSMS.
Katherine Turner - Exeter, NH 03833
Response from GSMS Air•Heating•Plumbing:

Thank you for the great review! I’m glad to hear our Specialist was able to get your water heater squared away and offer some extra tips while he was there. We always aim to go beyond just the repair, and I really appreciate you taking the time to share your experience. Thanks for choosing GSMS — it means a lot to our family and our team. – Zak D., Second-Generation Owner

Review
David DiNardo - Bedford, NH 03110
Response from GSMS Air•Heating•Plumbing:

Thank you for the 5 stars, David! We really appreciate you choosing GSMS and supporting our family-run team. If there’s ever anything more we can do for you, don’t hesitate to reach out. – Zak D., Second-Generation Owner

Review
claire lafond - Merrimack, NH 03054
Response from GSMS Air•Heating•Plumbing:

Thank you so much for the 5 stars, Claire! We’re grateful for your support and truly appreciate you choosing GSMS. It means a lot to our family and our entire team. – Zak D., Second-Generation Owner

Review
Great work, fair prices.
Tom Grasse - Manchester, NH 03104
Response from GSMS Air•Heating•Plumbing:

We thank you for sharing your positive experience. It made our day.

Review
top notch service, always professional. would recommend to anyone needing HVAC service, repair or install.
Ben Bouchard - Nashua, NH 03062
Response from GSMS Air•Heating•Plumbing:

It was a pleasure serving you and your family. Thank you for sharing your kind words with us. It means the world to us and to our entire team!

Review
Had an issue with our heat pump. Reached out for assistance and they had someone on site that afternoon. Problem was resolved quickly. Super friendly service. The tech was exceptionally friendly and an excellent communicator. Highly recommend
Mark Cooke - Greenland, NH 03840
Response from GSMS Air•Heating•Plumbing:

It was a pleasure serving you and your family. Thank you for sharing your kind words with us. It means the world to us and to our entire team!

Review
I needed to have shut off valves under my kitchen sink and a new hose attachment on my sprayer since the cheap plastic tubing was cracked. Mark was punctual, professional and extremely knowledgeable regarding the job. I am always impressed with GSM and how they run their family business. Mark completed the job quickly and efficiently. I can trust GSM and will continue to seek their help in the help in the future. GSM has installed a mini split, oil boiler, hot water heater in my home and I would highly recommend them to family and friends.
Kimberly Cichon - Newmarket, NH 03857
Response from GSMS Air•Heating•Plumbing:

We thank you for sharing your positive experience. It made our day.

Review
As usual, Jack's work is stellar.
Bob Bedrosian - Merrimack, NH 03054
Response from GSMS Air•Heating•Plumbing:

We are so glad to hear that you had a good experience.

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