Request Service Call Now Contact Us Coupons

Our Service Area

Book Online

Proudly serving New Hampshire homeowners with local heating, air & plumbing services.

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.

From air conditioning and heating services to plumbing repairs and installations, we ensure your home remains comfortable and efficient year-round. Our commitment to quality and customer satisfaction sets us apart as the trusted choice for all your home comfort needs.

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 4.9 out of 5 stars based on 151 customer reviews

Customers say: The reviews exhibit a positive sentiment towards Granite State Mechanical Services (GSMS). The majority of the reviews are positive, highlighting the quality of service, professionalism, and expertise of the staff. Customers appreciate the prompt and efficient service, with many expressing satisfaction with the work done. Positive reviews mention the friendly and knowledgeable technicians, the cleanliness of the installation, and the reasonable prices. Customers also emphasize the trustworthiness and reliability of GSMS, stating that they are the only plumber they will ever need. The positive reviews often mention specific individuals, such as Jack, Mark, and Quentin, who are praised for their knowledge, courtesy, and quality of work. However, there are a few negative reviews, which mainly focus on issues related to scheduling or communication. Customers express frustration with delays or unfulfilled promises, but these negative reviews are outweighed by the positive ones. Overall, the sentiment of the reviews is positive, with customers expressing satisfaction with the services provided by GSMS.

Job Locations and Reviews

Adam P.
Adam P. Checked in
Installation of a high-efficiency heat pump system to provide reliable and efficient cooling and supplemental heating to the home. Based on the load requirements and using the system for primary cooling and supplemental heating, we can design a single outdoor unit design. Existing electrical panels are code-approved with 200A service from the street. We will install a dedicated circuit which will serve each system.
Concord, NH 03301
Mark D.
Mark D. Checked in
Replaced outside faucet
Nashua, NH 03064
Mark D.
Mark D. Checked in
Replaced toilet and install outside faucet
Wilton, NH 03086
Qwentin G.
Qwentin G. Checked in
I called Rinnai tech-support when I got to the clients house. We ran through a couple tests while we had the hot water on and we were not able to recreate the problem it was having. We did find there to be a stored error code, code 10, which possibly indicates that the burners are dirty. I talked to the client and we are going to go through with cleaning the burners out.
Manchester, NH 03104
Review
Always very responsive to issues and both furnace issues resolved quickly
Rick - Salem, NH 03079
Mark D.
Mark D. Checked in
Checked plumbing no issues
Candia, NH 03034
Qwentin G.
Qwentin G. Checked in
Every thing looks good.
Londonderry, NH 03053
Qwentin G.
Qwentin G. Checked in
I washed the indoor coils with Dawn soap and water. I cleaned off the air filters. I noticed outside there is a piece of the cover garden missing.
Londonderry, NH 03053
Mark D.
Mark D. Checked in
Plumbing check and replaced tub/shower cartridge
Auburn, NH 03032
Qwentin G.
Qwentin G. Checked in
Filters
Londonderry, NH 03053
Qwentin G.
Qwentin G. Checked in
Replaced 3 20x20x1 air filters and 1 20x24x1 air filter on the upstairs air handler.
Londonderry, NH 03053
Review
Excellent service, very professional, and very helpful
Shawn - Gilmanton, NH 03837
Review
Quality work, great follow up and excellent communication with a reasonable price!
Matt from Barington - Barrington, NH 03825
Review
Excellent service!
Kristopher - Concord, NH 03303
Review
Mark is careful, knowledgable, efficient, and friendly Thanks!
Andy - Windham, NH 03087
Review
High recommend. Called GSMS because of a leak. Jack arrive and within minutes diagnosed the problem - and fixed it. Thank you
Ann - Merrimack, NH 03054
Review
Great service
Luc - Henniker, NH 03242
Review
Thank you for the great service!!
Steven - Windham, NH 03087
Review
Jack is the best. He goes out of his way to make sure we are taken care of and have what we need. He’s great
Currier - Manchester, NH 03104
Response from GSMS Air•Heating•Plumbing:

Thank you for taking the time to leave such a positive review! We're glad to hear you had a great experience with Jack.

Review
Jack is always very knowledgeable and kind and helpful when servicing our home. Thank you!
Alison - Londonderry, NH 03053
Response from GSMS Air•Heating•Plumbing:

We're thrilled to hear that you enjoyed your experience with us. Thanks for the kind words!

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.

Trusted Quality & Service
  • Best Of The Best
  • Expertise 2024
  • Lennox Premier Dealer
  • Mitsubishi Diamond Contractor
  • Rinnai
Request Service
servicereturningdetailscustomer schedule
*
Have we served you in the past? (Required)
Yes
No
*
To Serve You Best
Details Regarding Your Request (Required)
*
Your Contact and Service Location (Required)
*
*
What Date Would You Like To Schedule Your Service?(Required)
*
What time of day is best for you? (Required)
First Available
Morning
Afternoon
*
By pressing Submit I agree to receive phone, email, or text messages from GSMS Air•Heating•Plumbing to the provided mobile number and also agree to the GSMS Air•Heating•Plumbing terms and privacy policy. Message & data rates may apply. Consent is not a condition of purchase. We will never share your personal information with third parties for marketing purposes.
Back Next