Your Trusted Heating, AC & Plumbing Experts in Nashua, NH
Since 1987, GSMS has been proud to offer top-notch HVAC services to residents of Nashua, NH. With over three decades of experience, our family-owned business has built a reputation for excellence, reliability, and outstanding customer service. We provide a comprehensive range of HVAC services, including air conditioning repair, replacement, and maintenance, as well as heating services for furnaces and boilers. Our expert technicians are also skilled in installing and maintaining ductless mini-split systems, ensuring that your home stays comfortable year-round. At GSMS, we use only the highest quality products from leading manufacturers, guaranteeing efficient and long-lasting solutions for your HVAC needs. Whether you need a quick repair, a complete system installation, or regular maintenance, our team is dedicated to providing personalized service tailored to your specific requirements. Don’t let HVAC issues disrupt your comfort—call GSMS today at 603-424-8258 to schedule your HVAC service in Nashua, NH, and experience the difference of working with trusted local professionals.
In addition to our heating and air conditioning services, we offer top-quality plumbing services to the residents of Nashua, NH. With over three decades of experience, our family-owned business has established a reputation for trust, reliability, and exceptional customer care. Our comprehensive plumbing services include water heater repair, replacement, and maintenance for both tank and tankless models, ensuring your home has a consistent supply of hot water. We also specialize in kitchen plumbing, from faucet and sink installations to dishwasher and water line services. In the bathroom, our expert plumbers handle everything from toilet and shower repairs to vanity plumbing and pipe replacement. At GSMS, we use only the highest quality materials and the latest techniques to provide efficient and long-lasting solutions for your plumbing needs. Whether you require a quick repair, a complete installation, or regular maintenance, our team is committed to delivering personalized service tailored to your home’s unique requirements. Don’t let plumbing issues disrupt your daily routine—call GSMS today at 603-424-8258 to schedule your plumbing service in Nashua, NH, and experience the peace of mind that comes with working with trusted local professionals.
Recent Jobs and Reviews in Nashua, NH
Our Local Reviews by City
- Amherst, NH (3)
- Atkinson, NH (1)
- Auburn, NH (1)
- Barrington, NH (9)
- Bedford, NH (11)
- Candia, NH (2)
- Chester, NH (1)
- Concord, NH (4)
- Derry, NH (1)
- Epping, NH (1)
- Goffstown, NH (2)
- Henniker, NH (1)
- Hillsborough, NH (1)
- Hollis, NH (7)
- Hooksett, NH (5)
- Hudson, NH (4)
- Lee, NH (1)
- Londonderry, NH (6)
- Manchester, NH (30)
- Merrimack, NH (11)
- Milford, NH (3)
- Moultonborough, NH (1)
- Nashua, NH (16)
- New Boston, NH (2)
- Northfield, NH (1)
- Northwood, NH (1)
- Pembroke, NH (1)
- Raymond, NH (1)
- Rochester, NH (2)
- Salem, NH (2)
- Sandown, NH (1)
- Stratham, NH (1)
- Weare, NH (3)
- Windham, NH (3)
Job Locations and Reviews
Plumbing preventative maintenance
Excellent service.
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Tankless flush and troubleshoot humidifer.
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Plumbing inspection went great. I fixed the downstairs shower handle. I will send you an estimate to replace the basement toilet.
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Cut ceiling on first floor bath rm.Insulation was wet ran shower for 20min no leaks.Filled tub and drained no leaks.Sprayed walls with hand held shower a little water by shower valve sealed chrome plate
The visit showed what was the problem and will soon be resolved.
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The office will call to schedule the toilet replacement. Thank you.
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I started off today with performing a maintenance on a York. The client was having an issue where the furnace would blow cold air every once in a while. The only thing I found was that the air filter was backwards and the flame sensor was dirty. After I checked and adjusted the gas pressures to the manufacturer specifications, I performed a combustion analyzer test. I was checking for oxygen, CO2 and CO levels when I found that the CO was extremely high. After doing a few tests, I found that the heat exchanger is cracked. The unit is over 16 years old, so upon bringing up options to the client he wanted to replace the furnace. I shut the gas on the gas line off and the gas on the gas valve off. I turned the power off to the unit as well.
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Bathroom remodel project with Scott Woodbury. Disconnect and cap off the bathroom sink, toilet, and shower connections for demo. Tub unit will be replaced with a new unit purchased by the client. We will install the new base and rough-in plumbing. Once tile walls are complete, we will return to complete finish trim. New toilet will be set, new single-bowl vanity will be installed. Scott will open up the floor to look at the opportunity to relocate the existing HVAC vent from the door area to under the vanity as a toekick. A separate price will be proposed for that work, should it be possible. A rough estimated cost is listed on this proposal to serve as guidance only. All fixtures and components to be provided by the client.
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Repaired leak on second floor 3” drain
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Replacement of failed cast-iron Weil McLain forced-water gas boiler. Due to heat exchanger failure, credit will be issued by manufacturer towards the purchase of a new boiler. Manufacturer may require heat exchanger to be sent to them. If warranty claim is denied, client will be responsible for the claim amount. Boiler will be replaced as a direct replacement. The first floor radiant zone will be disconnected from the boiler and piped in through a newly installed radiant buffer tank. This buffer tank uses a plate heat exchanger and that will allow us to protect the boiler from any further oxygen getting into the system.
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Found old faucet not repairable. Customer brought new faucet for install. She would like to talk to Zak about enrollment into the home club
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Upsize outdoor condensate drain to 1 inch. Insulate 1inch pvc pipe outside and inside. If the problem persists please let us know. No charge- covered under labor warranty.
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Upon completing the maintenance we located a crack in the back pan of the heat exchanger. This is a safety concern and we are required to "red tag" the furnace and shut it off until the repair is completed. The heat exchanger is under warranty from the manufacturer. We propose to replace the failed heat exchanger. Warranty processing will be taken care of by GSMS but if the manufacturer denies warranty, the client is responsible for the part cost.
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I found the leak to be coming from the tub overflow. I disassembled, cleaned all surfaces, and reset the overflow with silicone. I also fixed the sink pop up. It's working good now but the holes on the vanity don't match the faucet the best. Thank you. No charge as the work is covered under our labor warranty.
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The first thing that I did today was vacuum the inside of the furnace and the supply box. The filter was very clean. Next, I cleaned the humidifier housing and replaced the humidifier pad. I inspected and checked all the wiring and all the connections are good. I checked the incoming gas pressure and it was in spec. I then ran the system in test mode and checked the manifold gas pressures and they were inspect. Lastly I did a combustion test to check for CO, CO2 and oxygen. The CO levels were extremely high in the flu pipe, so I investigated into what is happening. After conducting a few test, I ended up visually seeing and feeling that the heat exchanger failed. The bottom back of the heat exchanger had rust holes in it. I turned off the gas valve and I turned off the gas to the unit. I notified the client that he can’t run his furnace because it is extremely dangerous when dealing with a cracked heat exchanger. The heat exchanger ended up being under warranty and the client went thro
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Remove condensate pump and install drain into existing drain.
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Client noticed that water was leaking in the garage from the drain. The pitch of the PVC going outside was good. None of the PVC looked to be cracked or felt wet. There was no drip leg coming off of the 90 outside. I added a little piece with a slit in it. I insulated the drain line outside with foam tape. On the inside I re-spray foamed the hole. What it looks like was happening is on the really cold days the water was freezing up inside and then backing up into the garage and overflowing.
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Server room unit not keeping up. Mitsu remote had error 407 of battery in critical condition and cannot communicate with system. I replaced the batteries and watched the room lower from 77 to 70 deg F. Still running when I left. Thank you.
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Move oven closer to wall
I had 3 furnaces that needed repair work done. I received an estimate, approved the work which was scheduled and Jack got the repairs done.
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Replace 2" centrotherm elbow.
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Replace draft hood.
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Drain down boiler to replace expansion tank and air eliminator. When replacing the expansion tank the old taco air scoop cracked. I replaced the air scoop with a new caleffi air eliminator. I installed a new expansion tank. I replaced the rotted out draft hood.
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Drain down boiler system. Replace expansion tank. Refil boiler and purge air from system.
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Replace expansion tank and hyvent. Drain boiler down to perform work. Refil boiler and lurge air from system.
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Thawed drain line and insulated it.Blocked off fresh air grill
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Replace hot water heater
Mark is the best! Always takes care of the issues thoroughly!
We are so grateful for your 5-star review. Thanks for sharing your rating with us and the community.
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Meet inspector for gas inspection,connected generator and replaced expansion tank on hot water heater
Had a space heater that stopped working. Jack resolved the problem and got it working again.
Thank you for the wonderful review and for taking the time to share your feedback.
Great communication and service is always top notch.
Great service as always!
I needed a new dryer vent duct installed thru the basement and angled properly exiting the building.
Great service with excellent and honest communication throughout the appointment.
We count ourselves lucky for customers like you and look forward to working with you again in the future!
Excellent service
Zero complaints. Service was prompt, complete, and clean. Role model performance by technician.
Excellent service and such nice people to work with.
Many thanks for taking the time to share your feedback with us. We’re very happy to hear that we met your expectations!
Great Organization!
So trustworthy, nice and incredibly talented in their field. Any plumbing, heating or cooling needs…do yourself a favor and call Zak, Mark and Jack at GSMS.
Very grateful to have someone I can call who responds so quickly and is very fair and honest
Thank you for your kind words Kathleen! We're so grateful to have you a part of our GSMS family for so many years!