A-1 Guaranteed is a family-owned and operated business that serves HVAC and Solar Services Serving All Of Solano, Napa and Contra Costa Counties, Fairfield, Vacaville, and the Bay Area with Heating and Air Conditioning, Solar, Tankless Water Heaters, Windows, Insulation and/ or Duct Replacement needs. As one of the premier service businesses in the area, we have helped thousands of satisfied, loyal customers improve the energy efficiency of their homes and offices.