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
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
Bad control board. We will be back tomorrow
This is our highly recommended design utilizing premium Mitsubishi equipment. It utilizes the exact same second-floor layout and standard heat pump capabilities as Design 1, but upgrades the third-floor unit to a low-profile Floor-Mounted Console. Given the specific dimensions and ceiling angles of your third floor, this option provides the absolute cleanest aesthetic and optimal airflow. Scope of Work 1. Indoor Equipment (Third Floor - Floor Mount) Third Floor Space: Install one (1) Mitsubishi Floor-Mounted ductless console. Layout Adjustment: As we discussed during our consultation, utilizing this floor-mounted unit will require a minor rearrangement of the craft table furniture, but it guarantees the most unobtrusive and visually pleasing installation for this unique space. The exterior lines will drop down to meet the second-floor lines in a "T" and run horizontally along the roofline. 2. Indoor Equipment (Second Floor) Back Guest Bedroom: Install one (1) Mitsubishi wall-moun
Completed the AC maintenance today. I started off with washing the outdoor units coil with coil cleaner and water. I checked all the electrical connections and the capacitor and everything looked good. Next I went inside and I checked the air filter, that was clean. I checked the blower motor capacitor and electrical connections and everything looked good. I brushed and flushed the condensate trap with cleaner. Lastly I ran the unit in cooling mode. I connected my gauges and all my readings were coming back great.
Maintenance on 3 central air split systems & 2 HRV'S. Replace 3 air filters. I found 2 capacitors that need to be replaced.
found air trapped in second floor coil purged air from system everything's running fine
Completed the AC maintenances today. I started off with cleaning the outdoor condenser for the air handler. I cleaned the coil with coil cleaner and water. I checked all the electrical connections and the capacitor and everything looked good. Next I went inside and I cleaned the indoor coil with coil cleaner. I brushed and flushed the trap with cleaner. I checked the air filter and it was very clean. I checked electrical connections in the air handler and everything was good. I replaced the Lennox carbon and UV bulb. Next I washed the mini split outdoor unit. I cleaned the coil with coil cleaner and water. I cleaned outside of the unit with cleaner and a rag. I checked all the electrical connections and everything looked good. Next I went inside and I cleaned all the indoor heads coils with coil cleaner. I washed all the air filters with soap and water. I cleaned the outside of the units with cleaner and a rag. Lastly I ran all four mini-split heads in max heating and max fan. I was on
install customer sink and toilet
Replace condensate pump. Old one was all gunked up and float switch was malfunctioning.
Jack did an excellent job cleaning and servicing our mini-split. He is amiable, efficient, and professional. It was a great experience!!!
good service
Today I replaced the leaking circulator pump seal in the boiler. I also performed a heat exchanger flush. I replaced the condensate neutralization beads. I replaced the leaking high vent. I purged all the air out of the heating and the domestic hot water side. All returns came back nice and hot.
The best
Plumbing service estimate.
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Seems like a thorough inspection and update....great job Qwentin.
The service was really good. He did great work.
Always GREAT service
Qwentin did a great job. Highly recommend him.
Excellent, prompt service
It’s always a pleasure when Qwentin stops by; a polite and personable young man who is an asset to the formidable GSMS team who did another super, duper jobby! 😉 Hope he had a great time at the party celebrating multiple birthdays this weekend?! Cheers 👍🙂🥃🥃
Love dealing with this company. Their techs are always prompt, efficient and courteous. We've been happy to be their customer since 2010.
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
Qwentin was on time, very friendly and professional. He was able to identify the issue, communicate it effectively, and then fix it. Highly recommend.
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
Great water heater service. On time and professional l He gave me some helpful tips on other water related issues. Highly recommend GSMS.
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
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
top notch service, always professional. would recommend to anyone needing HVAC service, repair or install.
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!
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
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!
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.
We thank you for sharing your positive experience. It made our day.
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