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Merrimack, NH

Residential heating & air conditioning contractor in Merrimack, NH

GSMS is proud to serve the residents of Merrimack, NH, with top-quality heating and air conditioning services. As a family-owned business with over three decades of experience, we are dedicated to providing reliable, efficient, and professional HVAC solutions tailored to your home’s specific needs. 

GSMS is proud to be your Merrimack Lennox Premier Dealer!

Whether it's an emergency repair, a total replacement, or routine maintenance, we have you covered. Call 603-424-8258 today!

Air conditioner repair & replacement

  • AC Repair: We handle cooling problems big and small with speed and attention to detail. Our technicians are trained to troubleshoot and fix refrigerant leaks, thermostat issues, electrical failures, compressor problems, and more. 
  • AC Replacement and New Installation: Time for a cooling upgrade? We offer high-quality systems from Lennox and other leading manufacturers to improve efficiency, enhance comfort, and reduce homeowners' carbon footprint.

Furnace repair & replacement 

  • Furnace Repair: Dealing with a broken furnace? GSMS technicians work efficiently to track down even the smallest of problems and repair them in no time. Common furnace issues we repair include pilot light problems, thermostat malfunctions, ignition system failures, and blower motor problems. 
  • Furnace Replacement and New Installation: Upgrading your furnace takes your home's winter warmth to the next level. Our energy-efficient systems provide consistent heating, reduced maintenance, and enhanced safety. 

Boiler repair & replacement

  • Boiler Repair: Common boiler problems with pressure, thermostats, pilot lights, and leaks, can be a homeowner's nightmare. GSMS technicians work quickly to repair your boiler and get your home warm again in no time. 
  • Boiler Replacement and New Installation: Whether you are considering switching to a boiler system or it's time to replace your existing system, GSMS is here to help you increase efficiency and reliability with advanced units. 

Mini-split heat pumps

GSMS provides comprehensive services for mini-split heat pumps, including installation, maintenance, and repair. We specialize in Mitsubishi ductless units, known for their reliability and efficiency. Whether you’re looking to install a new system or need service for your existing mini-split heat pump, our technicians are here to ensure optimal performance and comfort in your home.

Ductwork cleaning & installation

  • Duct Cleaning: Regular duct cleaning helps improve air quality, increase HVAC efficiency, extend system lifespan, and eliminate odors. We use an advanced Roto Brush system to reach every corner of the ductwork and keep your home clean and comfortable. 
  • Duct Installation: Proper ductwork installation is crucial for airflow, efficiency, comfort, and durability. Choosing GSMS to install your ductwork gives you peace of mind that your new air ducts are safe and secure. 

Merrimack plumbing services

GSMS is proud to provide comprehensive plumbing services to homeowners in Merrimack, NH. Our experienced and professional team is dedicated to delivering reliable and efficient plumbing solutions tailored to your specific needs. 

Quick plumbing repairs, complete installations, and preventative maintenance are what we do best. Call 603-424-8258 today!

Water heater plumbers

  • Repair: Our skilled technicians can quickly diagnose and repair common water heater issues, including inconsistent temperature, leaks, and strange noises.
  • Replacement: When it’s time to replace your old water heater, we offer professional installation of both traditional tank models and modern tankless systems.
  • Maintenance: Regular maintenance is essential to keep your water heater running efficiently. Our comprehensive maintenance services include inspections, cleaning, and tune-ups.
  • Tankless Water Heaters: Upgrade to a tankless water heater for endless hot water, improved energy efficiency, and space savings. We provide expert installation and maintenance for these advanced systems.

Kitchen plumber services

  • Faucets: From repairing leaks to installing new faucets, we ensure your kitchen faucets are functioning perfectly.
  • Sinks: We handle all sink-related services, including installation, repair, and replacement, to keep your kitchen fully operational.
  • Garbage Disposals: Our team can install and repair garbage disposals, ensuring efficient waste management in your kitchen.
  • Dishwashers: We provide installation and repair services for dishwashers, making sure they are properly connected and running smoothly.
  • Water Lines: Whether you need new water lines installed or existing ones repaired, GSMS ensures a reliable water supply for your kitchen appliances.

Bathroom plumber services

  • Toilets: From fixing leaks and unclogging blockages to installing new toilets, we provide comprehensive toilet services.
  • Showers and Tubs: We offer repair, replacement, and installation services for showers and bathtubs to keep your bathroom comfortable and functional.
  • Sinks and Vanity Plumbing: Our team can install and repair bathroom sinks and vanity plumbing, ensuring everything operates seamlessly.
  • Pipe Repairs and Replacements: Whether it’s a minor leak or a major pipe replacement, GSMS provides expert pipe repair and replacement services to prevent water damage and maintain optimal plumbing performance.

Why choose GSMS in Merrimack?

  • Proven Track Record: With a long-standing presence in Merrimack, NH, GSMS has earned the trust of countless homeowners. Our dedication to excellence and reliability has made us a preferred choice for HVAC and plumbing services in the community. We are proud of our reputation and continually strive to uphold the high standards that have set us apart.
  • Local Expertise and Dedication: GSMS has been serving the Merrimack, NH community for over three decades, building a reputation for excellence and reliability. As a family-owned business, we are deeply committed to our local community and understand the unique needs of Merrimack homeowners. Our local expertise allows us to provide tailored solutions that keep your home comfortable and efficient year-round.
  • Comprehensive Range of Services: From HVAC to plumbing, GSMS offers a full spectrum of services to meet all your home comfort needs. Our skilled technicians are trained in the latest technologies and techniques, ensuring top-quality service for every job. Whether you need a quick repair, a new installation, or regular maintenance, we have the expertise to get the job done right.

Become a GSMS Home Club member today

Join the GSMS Home Club and enjoy exclusive benefits designed to keep your home’s HVAC and plumbing systems in top condition. Membership perks include:

  • Priority Service
  • No Diagnostic Fees
  • 10% Off Repairs
  • Home ID and Smart Monitoring
  • Monthly Credits Towards Major Purchases
  • Regular Maintenance
  • Labor Warranty Upgrades

Call today for great service in Merrimack.

Trust the experts at GSMS to provide reliable, efficient, and top-quality services tailored to your needs. Whether you need a quick repair, a new installation, or regular maintenance, our dedicated team is here to ensure your Merrimack home remains comfortable and functional year-round.

Call 603-424-8258 today or fill out our online contact form to book an appointment!

Recent Jobs and Reviews in Merrimack, NH

Rated 5.0 out of 5 stars based on 42 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
Snake upstairs guest bathroom tub shower.
Merrimack, NH 03054
Jack D.
Jack D. Checked in
Fix leaking tub drain. Disassembled and revealed drain. Thank you!
Merrimack, NH 03054
I completed the gas furnace maintenance today. I started off with checking all the wiring connections and everything looked good. I found that the capacitor for the blower motor was starting to fail so the client had me replace it. I vacuumed out the inside of the furnace. The heat exchanger and the burners were very clean for how old the unit is. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly I ran the unit and performed a combustion analyzer test that checks the units CO, CO2 and oxygen levels. The furnace was running great.
I completed the gas furnace maintenance today. I started off with checking all the wiring connections and everything looked good. I found that the capacitor for the blower motor was starting to fail so the client had me replace it. I vacuumed out the inside of the furnace. The heat exchanger and the burners were very clean for how old the unit is. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly I ran the unit and performed a combustion analyzer test that checks the units CO, CO2 and oxygen levels. The furnace was running great.
Qwentin G.
Qwentin G. Checked in
I completed the gas furnace maintenance today. I started off with checking all the wiring connections and everything looked good. I found that the capacitor for the blower motor was starting to fail so the client had me replace it. I vacuumed out the inside of the furnace. The heat exchanger and the burners were very clean for how old the unit is. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly I ran the unit and performed a combustion analyzer test that checks the units CO, CO2 and oxygen levels. The furnace was running great.
Merrimack, NH 03054
Qwentin G.
Qwentin G. Checked in
Found that the zone valve head was faulty. Replaced it with a new OEM matchup and tested operation and everything was working as it should.
Merrimack, NH 03054
I found that the boiler was off on a error code because the condensate trap was clogged. It was completely filled with calcium deposits. I pulled the trap apart and I rinsed it out with hot water and soap. I put it all back together and tested operation and everything was working as it should. I found that a connection to the circulator pump inside of the boiler was slightly leaking. I found that the neutralizer beads were caked up with calcium deposits as well and found that the high vent was leaking. The heat exchanger was also pretty dirty inside so I will send over an estimate for those repairs and cleaning of the heat exchanger.
I found that the boiler was off on a error code because the condensate trap was clogged. It was completely filled with calcium deposits. I pulled the trap apart and I rinsed it out with hot water and soap. I put it all back together and tested operation and everything was working as it should. I found that a connection to the circulator pump inside of the boiler was slightly leaking. I found that the neutralizer beads were caked up with calcium deposits as well and found that the high vent was leaking. The heat exchanger was also pretty dirty inside so I will send over an estimate for those repairs and cleaning of the heat exchanger.
Qwentin G.
Qwentin G. Checked in
I found that the boiler was off on a error code because the condensate trap was clogged. It was completely filled with calcium deposits. I pulled the trap apart and I rinsed it out with hot water and soap. I put it all back together and tested operation and everything was working as it should. I found that a connection to the circulator pump inside of the boiler was slightly leaking. I found that the neutralizer beads were caked up with calcium deposits as well and found that the high vent was leaking. The heat exchanger was also pretty dirty inside so I will send over an estimate for those repairs and cleaning of the heat exchanger.
Merrimack, NH 03054
Jack D.
Jack D. Checked in
Add boiler weld to boiler. I adjusted hi and low limit to try and have the boiler fire less frequent. Please check it as often as you can to ensure the leak seals. We will send over an estimste to replace the boiler.
Merrimack, NH 03054
Found leak on boiler,needs a price for new boiler. Would like to try boiler stop additive.
Found leak on boiler,needs a price for new boiler. Would like to try boiler stop additive.
Adam P.
Adam P. Checked in
Found leak on boiler,needs a price for new boiler. Would like to try boiler stop additive.
Merrimack, NH 03054
Review
The experience started with Gina in the office who was very responsive and accommodating and made the scheduling process super efficient and friendly. Then Mark came and brought his expertise to my home and systems to point areas of installation failures by the company that installed my system. Just using the basic manual to point out how they cut corners. Mark spent the time to correct the exhaust piping to fix leaks and improve air flow. He was friendly and accommodating.
Nelson - Merrimack, NH 03054
Mark D.
Mark D. Checked in
Trim foam from vent pipe
Merrimack, NH 03054
Qwentin G.
Qwentin G. Checked in
Replaced the Lennox carbon MERV 16 filter and UV bulb.
Merrimack, NH 03054
Adam P.
Adam P. Checked in
Drywall
Merrimack, NH 03054
Pm on furnace.found leak in exhaust vent and wrong size intake vent.Redid both vents.Cleaned lav stopper on second floor lav sink.
Pm on furnace.found leak in exhaust vent and wrong size intake vent.Redid both vents.Cleaned lav stopper on second floor lav sink.
Mark D.
Mark D. Checked in
Pm on furnace.found leak in exhaust vent and wrong size intake vent.Redid both vents.Cleaned lav stopper on second floor lav sink.
Merrimack, NH 03054
Mark D.
Mark D. Checked in
Installed 3 toilets
Merrimack, NH 03054
Oil furnace preventative maintenance. Everything looks great on your system. Please see the maintenance sheet for todays details of visit.
Oil furnace preventative maintenance. Everything looks great on your system. Please see the maintenance sheet for todays details of visit.
Jack D.
Jack D. Checked in
Oil furnace preventative maintenance. Everything looks great on your system. Please see the maintenance sheet for todays details of visit.
Merrimack, NH 03054
Review
Very happy with the job done.
Barb - Merrimack, NH 03054
I completed the gas furnace maintenance today. I started off with checking all electrical connections and everything looked good. I pulled and cleaned the flame sensor. I flushed the trap and condensate pump cleaner with cleaner. I vacuumed out the filter box and inside of the furnace. I replaced the air filter with a 20 x 25 x 5 air bear filter. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit to check the CO, CO2 and oxygen levels and the furnace was running great.
I completed the gas furnace maintenance today. I started off with checking all electrical connections and everything looked good. I pulled and cleaned the flame sensor. I flushed the trap and condensate pump cleaner with cleaner. I vacuumed out the filter box and inside of the furnace. I replaced the air filter with a 20 x 25 x 5 air bear filter. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit to check the CO, CO2 and oxygen levels and the furnace was running great.
Qwentin G.
Qwentin G. Checked in
I completed the gas furnace maintenance today. I started off with checking all electrical connections and everything looked good. I pulled and cleaned the flame sensor. I flushed the trap and condensate pump cleaner with cleaner. I vacuumed out the filter box and inside of the furnace. I replaced the air filter with a 20 x 25 x 5 air bear filter. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit to check the CO, CO2 and oxygen levels and the furnace was running great.
Merrimack, NH 03054
Mark D.
Mark D. Checked in
Change wire harness to gas valve pm on rinnai
Merrimack, NH 03054
Completed the gas furnace maintenance today. I started off with replacing the 20 x 25 x 5 air bear filter and I replaced the humidifier pad as well. I vacuumed up the air filter box and the humidifier box. I pulled and cleaned the flame sensor. I checked all the wiring connections and everything looked good. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test that checks for CO, CO2 and oxygen levels and the furnace was running great.
Completed the gas furnace maintenance today. I started off with replacing the 20 x 25 x 5 air bear filter and I replaced the humidifier pad as well. I vacuumed up the air filter box and the humidifier box. I pulled and cleaned the flame sensor. I checked all the wiring connections and everything looked good. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test that checks for CO, CO2 and oxygen levels and the furnace was running great.
Qwentin G.
Qwentin G. Checked in
Completed the gas furnace maintenance today. I started off with replacing the 20 x 25 x 5 air bear filter and I replaced the humidifier pad as well. I vacuumed up the air filter box and the humidifier box. I pulled and cleaned the flame sensor. I checked all the wiring connections and everything looked good. I checked incoming and outgoing gas pressures and everything was according to manufacture specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test that checks for CO, CO2 and oxygen levels and the furnace was running great.
Merrimack, NH 03054
Mark D.
Mark D. Checked in
Replace flapper in toilet. Look at toilet that appears to be leaking. We could not find anything. Please keep an eye on it and if you find a leak you are better off to put a new toilet in given the age of the toilet and the parts it already needs to have replaced.
Merrimack, NH 03054
Completed gas piping to gas generator
Completed gas piping to gas generator
Adam P.
Adam P. Checked in
Completed gas piping to gas generator
Merrimack, NH 03054
Review
Quick service call to replace thermostat. Done in about 15 minutes, explained the workings. Very satisfied Great service as usual
Joseph - Merrimack, NH 03054
Jack D.
Jack D. Checked in
Install Honeywell T6 estate. Program automated. Remeber to pnly use auto in late spring and early fall.
Merrimack, NH 03054
Mark D.
Mark D. Checked in
Check water pressure 65 psi after pressure reducing valve.I would recommend replacing pressure reducing valve it's over 20 years old. Average life is 8 to 12 years.Will check in hammer arrestor valve also
Merrimack, NH 03054
I completed the gas furnace maintenance today. I checked all electrical connections and everything looked good. I pulled and cleaned the flame sensor. The client replaced her air filter recently. Checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great. I talked to the client about adding a UV light and a leak breaker on her water heater. I will email her over the estimates for those.
I completed the gas furnace maintenance today. I checked all electrical connections and everything looked good. I pulled and cleaned the flame sensor. The client replaced her air filter recently. Checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great. I talked to the client about adding a UV light and a leak breaker on her water heater. I will email her over the estimates for those.
Qwentin G.
Qwentin G. Checked in
I completed the gas furnace maintenance today. I checked all electrical connections and everything looked good. I pulled and cleaned the flame sensor. The client replaced her air filter recently. Checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great. I talked to the client about adding a UV light and a leak breaker on her water heater. I will email her over the estimates for those.
Merrimack, NH 03054
Review
Jack was polite and very neat.
Sharon - Merrimack, NH 03054
Jack D.
Jack D. Checked in
Replace bathroom faucet.
Merrimack, NH 03054
I added one bag of gravel by generator where rodent dug a hole. The GSMS HomeClub heating visit was completed today. Your 2 stage Lennox furnace is in great condition. Please see the maintenance form for details.
I added one bag of gravel by generator where rodent dug a hole. The GSMS HomeClub heating visit was completed today. Your 2 stage Lennox furnace is in great condition. Please see the maintenance form for details.
Jack D.
Jack D. Checked in
I added one bag of gravel by generator where rodent dug a hole. The GSMS HomeClub heating visit was completed today. Your 2 stage Lennox furnace is in great condition. Please see the maintenance form for details.
Merrimack, NH 03054
Review
We have been working with GSMS for 8 years. They provide the best service for installs and maintenance. The people are very professional, friendly and do great work. Today Qwentin was the tech doing the service maintenance. This young man came at the time scheduled, knew what he was doing and did excellent work. If you are in need for heating, air conditioning and plumbing work, this is the company for you!
Claire - Merrimack, NH 03054
Completed the gas furnace maintenance. I start off checking all the wiring connections and everything looked good. The air filter looks brand new so I didn’t replace it. I replaced the humidifier pad and turned on the humidifier for winter mode. I pulled and cleaned the flame sensor. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit in low and high fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great.
Completed the gas furnace maintenance. I start off checking all the wiring connections and everything looked good. The air filter looks brand new so I didn’t replace it. I replaced the humidifier pad and turned on the humidifier for winter mode. I pulled and cleaned the flame sensor. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit in low and high fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great.
Qwentin G.
Qwentin G. Checked in
Completed the gas furnace maintenance. I start off checking all the wiring connections and everything looked good. The air filter looks brand new so I didn’t replace it. I replaced the humidifier pad and turned on the humidifier for winter mode. I pulled and cleaned the flame sensor. I checked incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly I ran the unit in low and high fire and performed a combustion analyzer test to check for CO, CO2 and oxygen levels and everything was running great.
Merrimack, NH 03054
I replaced the modulating gas valve today. I checked operation and everything was running perfect. I also completed the furnace maintenance today as well. The air filter that was in it looked brand new so I didn’t replace it. I replaced the humidifier pad. Cleaned the flame sensor. I checked all the wiring connections and everything looked good. I tested incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test. This test checks for CO, CO2 and oxygen levels and everything was running great. I noticed that there is corrosion on the plug going into the gas valve that wasn’t able to be cleaned off. I let the clients know and told them that I would send them over an estimate to replace the wiring harness.
I replaced the modulating gas valve today. I checked operation and everything was running perfect. I also completed the furnace maintenance today as well. The air filter that was in it looked brand new so I didn’t replace it. I replaced the humidifier pad. Cleaned the flame sensor. I checked all the wiring connections and everything looked good. I tested incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test. This test checks for CO, CO2 and oxygen levels and everything was running great. I noticed that there is corrosion on the plug going into the gas valve that wasn’t able to be cleaned off. I let the clients know and told them that I would send them over an estimate to replace the wiring harness.
Qwentin G.
Qwentin G. Checked in
I replaced the modulating gas valve today. I checked operation and everything was running perfect. I also completed the furnace maintenance today as well. The air filter that was in it looked brand new so I didn’t replace it. I replaced the humidifier pad. Cleaned the flame sensor. I checked all the wiring connections and everything looked good. I tested incoming and outgoing gas pressures and everything was according to manufacturer specifications. Lastly, I ran the unit in high and low fire and performed a combustion analyzer test. This test checks for CO, CO2 and oxygen levels and everything was running great. I noticed that there is corrosion on the plug going into the gas valve that wasn’t able to be cleaned off. I let the clients know and told them that I would send them over an estimate to replace the wiring harness.
Merrimack, NH 03054
Review
Jack did a great job. Provided a lot of good information. Thank you
Don - Merrimack, NH 03054
Review
Excellent service
Kathleen - Merrimack, NH 03054
Review
Excellent Service
Sharon - Merrimack, NH 03054
Review
Excellent
Sharon - Merrimack, NH 03054
Review
Quentin was awesome he was very professional, respectful and extremely knowledgeable and competent. Great personality. and exhibited interpersonal and communication skills.
Ronald - Merrimack, NH 03054
Review
Never problem with GSMS! They have installed and serviced my furnace and AC for 27 years. Over the years Mark has gone out of his way to fix problems and now crew is continuing his great service! I have recommended them to many people.
Joseph - Merrimack, NH 03054
Review
Very good experience - good communication from Gina about scheduling. Techs (Jack and Qwentin) showed up on time and completed the job (new hot water heater and related cleanup) efficiently.
Ann - Merrimack, NH 03054
Review
Qwentin is a valued team member of GSMS (Granite State Mechanical Services). He is friendly and knowledgeable
Tom F - Merrimack, NH 03054
Review
Qwentin was on time and provided excellent service as always
Tom F - Merrimack, NH 03054
Review
Excellent in all areas of service. Punctual, courteous, kept us well informed of service progress. Upon completion of the furnace installation Adam explained all features of the new system , and addressed questions . The above statement can be said of all GSMS employees as we have used them over the years for several different systems installation. Excellent in all areas.
Bob M - Merrimack, NH 03054
Review
Excellent service
Sylvie - Merrimack, NH 03054
Review
Friendly and knowledgeable
Trevor - Merrimack, NH 03054
Review
Everything is working great!
Brendan - Merrimack, NH 03054
Review
GSMS helped us out after I discovered water surrounding the furnace. Qwentin quickly found the issue, explained what happened and what needed to be fixed. Great communication, excellent service, and he left the area cleaner than he found it. GSMS is always a pleasure to work with.
Sam - Merrimack, NH 03054
Review
Five Stars
Ellen - Merrimack, NH 03054
Review
Couldn’t have asked for a better installation of dishwasher/toilets. Mark was very personable and professional. Arrived on time and finished on time. Excellent experience
Wayne - Merrimack, NH 03054
Review
Very professional in all respects.
BJ - Merrimack, NH 03054
Review
I have been working with GSMS for close to 8 or 9 years now. Had them replace my entire HVAC system and on demand hot water heater installed. Today just had my annual service for my HVAC unit done. They really do great work and all their technicians are very skilled and knowledgeable. I highly recommend them for anybody for your HVAC and plumbing needs!
Scott - Merrimack, NH 03054
Review
Great overall service, always has done a great job for me!
Al - Merrimack, NH 03054
Review
Mark and his entire team do a wonderful job. Show up on time and treat your home with respect. Recommend them without reservations.
Tom - Merrimack, NH 03054
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
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