GSMS Air•Heating•Plumbing

Founded in 1987 by Mark Downing, Granite State Mechanical Services has provided professional installation and service of heating, cooling, and plumbing products for New Hampshire’s homeowners and businesses for over 30 years. Throughout the course of 3 decades, we’ve learned a lot and still to this day continue to innovate to always make sure we are arriving to a customer’s home as the Service Specialists™. Now entering into 35+ years of serving our New Hampshire homeowners and local businesses, Mark’s two sons Zak & Jack are fully involved as the second generation. You can find Zak running the business as well as visiting customers to look at projects. Jack is our Service Manager, leading our team of Service Specialists repairing and maintaining the advanced systems used to heat and cool NH homes. Together they lead a bright future for GSMS. When you need service or repairs on your home’s heating, cooling, or plumbing system we are ready to serve you. From the moment you call our office to when our truck is backing out of your drive, your experience with GSMS will be exceptional. We strive to train and educate our Specialists so they have the knowledge and experience to properly provide you with service.