Your Trusted Heating & AC Repair Experts in Concord, NH
Since 1987, GSMS has been proud to offer top-notch HVAC services to residents of Concord, 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.
Ductless Mini Split Systems
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.
Get the Best HVAC Service in Concord
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 Concord, NH, and experience the difference of working with trusted local professionals.
Local Concord Plumbers
In addition to our heating and air conditioning services, we offer top-quality plumbing services to the residents of Concord, 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
- Kitchen and Bathroom plumbing services, from faucet and sink installations to dishwasher and water line services.
Our expert plumbers handle everything from toilet and shower repairs to vanity plumbing and pipe replacement.
Expert Plumbing Service Solutions
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 Concord, NH, and experience the peace of mind that comes with working with trusted local professionals.
Recent Jobs and Reviews in Concord, NH
Our Local Reviews by City
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Job Locations and Reviews
The service technicians are awesome great friendly guys. The installation was awesome. They did a very efficient job. Glad to be working with GSMS. Thank You!
This proposal outlines the installation of a high-efficiency, multi-zone Mitsubishi ductless system designed primarily to provide excellent summer cooling and supplemental shoulder-season heating for your main living level. Future-Proofing Your Home: As we discussed, we are intentionally sizing the new multi-zone outdoor condenser with extra capacity. This ensures that when you are ready to condition your basement space (near the electrical panel), we can simply return and add a 6,000 BTU indoor head to this existing outdoor unit without needing to upgrade the core equipment. Scope of Work 1. Outdoor Equipment & Placement The Condenser: We will supply and set one (1) multi-zone Mitsubishi standard heat pump condenser (cooling-focused) on a new equipment pad. Location: The unit will be placed on the gable end of the home near the gas meter. We will carefully measure and install the unit to ensure it maintains all strict, code-required clearance distances from the gas utility equipm
Replace pressure gauge on booster pump. Recalibrate booster pump settings. Test operation.
Completed the mini split and central AC maintenance. Everything went great. Please see the attached forms.
I’ve used GSMS for years now. They have always provided top notch services and workmanship. Shout out to Jack specifically for today help 🙌🏻
I believe that the three way valve in the boiler was sticking and caused the domestic hot water to trigger a boiler high limit lockout. I reccomend replacing the boiler due to its age.
This proposal outlines the installation of a 3-zone Mitsubishi Hyper Heat ductless system for your home. Because this system will be a primary heat source for the bedrooms, I am utilizing the advanced FX Series indoor heads. These specific units are engineered to deliver their true, rated heating BTUs even in the bitter cold, ensuring your family stays perfectly warm all winter long. Scope of Work 1. Outdoor Equipment & Site Prep Condenser Installation: Supply and install one (1) multi-zone Mitsubishi Hyper Heat outdoor condenser on the back side of the home. Site Preparation: As we discussed during my visit, you will be removing the existing section of fence prior to our arrival so we have the necessary clearance to position the unit in its optimal location. Winterization: Because this is a Hyper Heat system, we will mount the unit on a heavy-duty snow stand and install a protective weather baffle ("ice hat") to protect the fan motor and coils from winter snow and ice accumulatio
Completed the mini split Maintenance today. Everything went great. Please see the attached form.
Completed the AC maintenance today. Everything went great. Please see the attached form.
GSMS HOMECLUB MAINTENANCE
Friendly, efficient service
Completed the mini split maintenance today. Everything went great. Please see the attached form.
This proposal outlines the installation of high-efficiency 4-Zone Mitsubishi ductless mini-split system. This system is engineered to provide perfectly zoned, independent summer cooling, as well as highly efficient supplemental heating during the shoulder seasons for both the upstairs and basement living spaces. Scope of Work 1. Outdoor Equipment Installation Condenser Placement: Supply and install one (1) Mitsubishi 4-Zone outdoor heat pump condenser. The unit will be professionally mounted on the exterior gable end of the home, located to the right of the existing electrical meter. 2. Indoor Air Distribution (4 Wall-Mounted Units) Supply and install four (4) precisely sized Mitsubishi wall-mounted ductless air handlers in the following dedicated zones: Zone 1: Basement Living Room: Mounted on the entry wall adjacent to the electrical panel for optimal airflow distribution across the living space. Zone 2: Basement Bedroom: Strategically mounted on the back wall near the right r
Replaced the faulty flow switch. Bled all the air out of the zones. All the returns came back hot.
Boiler flow switch is bad. I installed temporary low water cut off in order to keep the boiler on line for the residents. We will order the switch and return this week to replace it.
Replacement of the existing unit and installation of a new Sterling Ensemble tub & shower unit. The new unit will be a right-hand drain configuration and will include a standard Moen Chateau polished chrome valve with a standard shower head and tub spout. For enhanced functionality, the shower arm will feature a Kohler Awaken transfer valve connected to a Kohler Awaken handheld shower with a 60" hose, all in matching polished chrome finish. Note: The interior water height of the new tub is 11", with the top of the tub sitting at 16". The existing waste and supply lines will be reconnected at the point-of-use. This installation includes all necessary plumbing materials and labor, but any carpentry finish work is explicitly not included.
Fix leaking vent
Baseboard loop in "mud room" froze and burst. The Tennant said that the room was always cold. We cut it out of the first floor heat loop and bypassed it. Thank you!
Installed the new collector box and all gaskets. Installed the new trap as well and primed it. Ran the unit and checked for leaks and there was no leaks. Performed a combustion analyzer test that checks the units CO, CO2 and oxygen levels and everything was running great. Client signed up for home club. He wants us to come out in the fall to do his furnace maintenance and spring/summer to do the AC.
Apon arrival I found that the first floor zone was calling. I found that the circulator pump had burned out. The circulator pump was extremely hot. I replaced it with a new pump. I bled all the air out of the system. Both returns came back very hot.
Upon arrival first floor zone was working perfectly fine. The circulator pump was working and the return was coming back very hot. I checked a few things inside of the boiler and everything looked good. The only thing that I could think of was that a pipe froze somewhere for the first floor. After the second floor zone had called for a while it was able to thaw itself out. If this happens again please give us a call. I also noticed that the waste main is leaking. I will also email over a couple pictures.
Found that the collector box gasket has failed. We ordered the new gaskets and will let the client know as soon as possible when we can come out to repair it.
Boiler repairs.
Replace client provided bathroom faucet. Check for leaks. All set thank you!
Completed the gas furnace maintenance today. I started off with cleaning the flame sensor. I checked all the wiring connections and the capacitor and everything looks great. The air filter was clean, the client replaces his own filters. I flushed the trap and condensate pump with cleaner. I checked incoming gas pressure and that was according to manufacture specifications. Lastly, I ran the unit in low and high fire and performed a combustion analyzer test to check the CO, CO2 and oxygen levels. The furnace was running great.
Annual GSMS HomeClub PM on Viessmann boiler. Everything was gone through and your boiler is in great condition. Ready for another winter of dependable heat! I also flushed the water heater tank and removed/ inspected anode rod! All set. Thank you!
Excellent service!
I completed the gas furnace maintenance and the maintenance of the air handler in the attic. I started off with the gas furnace. I checked all the wiring connections and everything looked good. I pulled and cleaned the flame sensor. I changed the air filter with the filter that the client supplied. Vacuumed out the air filter box and the furnace. I 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 that checks for, CO, CO2 and oxygen levels. Everything was running great. Next I completed the maintenance on the air handler. I checked the wiring connections and everything looked good. The air filter was very dirty and the client ordered new filters that he was going to replace his self.
Measure for tub replacement
Adam is amazing! Friendly, professional, competent and clearly explains technical issues.
Excellent service!
We’ve been so happy with the products and service from GSMS! I absolutely recommend them!
Adam install a heat pump system in our home, which required not just one but two complete systems with air exchange. From start to finish, Adam was courteous, professional, and an absolute pleasure to work with. He took the time to answer all our questions, ensured the installation process went smoothly, and worked with us every step of the way. The quality of his work was exceptional—everything was done meticulously, and the system is running perfectly. Adam’s attention to detail and dedication to doing the job right were clear throughout the project. We couldn’t be happier with the results
We’ve used GSMS for several years- three major projects at two different houses- and they’ve always been top notch! Great communication, reliability, and professionalism. We always recommend GSMS to anyone we know with HVAC needs.
GSMS is always professional and courteous. We always go to them with any plumbing and heating needs.








