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Our Service Area

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 499 customer reviews

Customers say: The overall sentiment across these reviews is overwhelmingly positive, reflecting high levels of customer satisfaction and appreciation. Customers consistently express enthusiasm about the quality of service they received, with recurring praise for professionalism, expertise, and efficiency. A dominant theme throughout is the technical skill and knowledge demonstrated by the service team, with many reviewers highlighting how thoroughly problems were diagnosed and resolved. The interpersonal qualities of the technicians emerge as another strong positive trend, with customers frequently describing them as friendly, personable, pleasant, and respectful. Communication stands out as a particularly valued aspect, with reviewers appreciating clear explanations, patience in answering questions, and being kept informed throughout the service process. Timeliness and punctuality are consistently mentioned as strengths, alongside respect for customers' property and maintaining clean, orderly work practices. Many customers express strong loyalty and trust in the company, with several indicating they are repeat customers or plan to continue using the service. The tone is enthusiastic and grateful, with multiple reviewers offering strong recommendations and expressing genuine happiness with the results. Overall, these reviews paint a picture of a service provider that excels in both technical competence and customer care, creating consistently positive experiences that foster long-term customer relationships.

At a glance

GSMS Air•Heating•Plumbing has completed 10 jobs in October 2026.

The 25 customer reviews shown here average 5.0 out of 5.

The most recent job was on October 9, 2026.

Recent work covers Manchester, NH, Bedford, NH, Merrimack, NH, Stratham, NH and Bow, NH.

Job Locations and Reviews

GSMS HOMECLUB FURNACE MAINTENANCE.
GSMS HOMECLUB FURNACE MAINTENANCE.
Jack D.
Jack D. Checked in
GSMS HOMECLUB FURNACE MAINTENANCE.
Manchester, NH 03109
Completed the gas boiler maintenance today. Everything went great. Please see the attached form.
Completed the gas boiler maintenance today. Everything went great. Please see the attached form.
Qwentin G.
Qwentin G. Checked in
Completed the gas boiler maintenance today. Everything went great. Please see the attached form.
Nashua, NH 03062
Jack D.
Jack D. Checked in
Mini split preventative maintenance. Please see form for details of today's servicing.
Bedford, NH 03110
Completed the gas furnace maintenance today. Everything went great! I replaced the air filter and the humidifier pad. Please see the attached forms.
Completed the gas furnace maintenance today. Everything went great! I replaced the air filter and the humidifier pad. Please see the attached forms.
Qwentin G.
Qwentin G. Checked in
Completed the gas furnace maintenance today. Everything went great! I replaced the air filter and the humidifier pad. Please see the attached forms.
Stratham, NH 03885
Completed the boiler maintenance today. Everything went great! Please see the attached form.
Completed the boiler maintenance today. Everything went great! Please see the attached form.
Qwentin G.
Qwentin G. Checked in
Completed the boiler maintenance today. Everything went great! Please see the attached form.
Epping, NH 03042
GSMS HOMECLUB HEATING PM!
GSMS HOMECLUB HEATING PM!
Jack D.
Jack D. Checked in
GSMS HOMECLUB HEATING PM!
Auburn, NH 03032
Review
Qwentin provided excellent service today. He is a very professional and personable young man. Granite State is lucky to have him on their team.
Al - Bow, NH 03304
Review
Jack came right on time and figured out my heating problem right away. He got me a new thermostat, installed it and the price was very fair for his time and the new thermostat.
BJ - Merrimack, NH 03054
Completed the furnace maintenance today. Everything went great. I replaced the air filter and the humidifier pad. Please see the attached maintenance form.
Completed the furnace maintenance today. Everything went great. I replaced the air filter and the humidifier pad. Please see the attached maintenance form.
Qwentin G.
Qwentin G. Checked in
Completed the furnace maintenance today. Everything went great. I replaced the air filter and the humidifier pad. Please see the attached maintenance form.
Bow, NH 03304
Jack D.
Jack D. Checked in
Diagnosed a faulty upstairs thermostat that wouldn't turn the heat on. I repaced with a new one and made sure it worked. Thank you!
Merrimack, NH 03054
Completed the gas furnace maintenance today. Everything went great. I replaced the inducer motor capacitor since it was failing. Please see the attached maintenance form.
Completed the gas furnace maintenance today. Everything went great. I replaced the inducer motor capacitor since it was failing. Please see the attached maintenance form.
Qwentin G.
Qwentin G. Checked in
Completed the gas furnace maintenance today. Everything went great. I replaced the inducer motor capacitor since it was failing. Please see the attached maintenance form.
Manchester, NH 03109
Jack D.
Jack D. Checked in
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
Review
GSMS has been the most professional and helpful company we have worked with. They have helped with a handful of small project with plumbing and heating issues leading up to them installing a brand new boiler into our home. They were always willing to answer any questions I had and even made noise visits to talk about the project which was greatly appreciated. Every person that has come to help us out has been so knowledgeable, friendly, and helpful which makes the project so much better. The new installation of the boiler went smoothly and they were able to explain everything going on to me when I asked and left me feeling so great with the new unit that was put In. We will continue use GEMS due to their fair pricing, great quality of work, and the personal care you can feel from everyone that you work with.
Brian Fox - Manchester, NH 03102
Response from GSMS Air•Heating•Plumbing:

Wow, I am so appreciative of you sharing your experience Brian! We work so hard each and every day to ensure we deliver this experience. Thank you for trusting my team and I with your home and we welcome you to the GSMS Family! -Zak

Review
Great service and communication from start to finish. Would highly recommend.
Dina - Northfield, NH 03276
Review
On time, courteous, and efficient.
Tom - Merrimack, NH 03054
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.
Ted - Amherst, NH 03031
Review
Excellent
Raymond - Stratham, NH 03885
Review
Excellence
Raymond - Epping, NH 03042
Review
Excellent!
Jeffrey - Stratham, NH 03885
Review
Qwentin seemed knowledgeable, was very personable, efficient
Nancy - Stratham, NH 03885
Review
Always wonderful with Quentin
Bonnie - Bedford, NH 03110
Review
Michael Downing - Newbury, NH 03255
Review
Mark was excellent! Thank you.
Diane Ferland - Manchester, NH 03102
Review
Quentin is very professional, he answered all my questions regarding heating and problems with my humidifier. Thank you.
Pavel Novak - Londonderry, NH 03053
Review
Great job
Hanna Zbyszynska - Manchester, NH 03103
Review
Martha Belanger - Barrington, NH 03825
Review
Ariel M. Oxaal - Barrington, NH 03825
Review
Louise Cyr - Henniker, NH 03242
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!

Zak Downing

Zak Downing

Get to Know Zak Downing
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