Loos & Sons HVAC LLC

Loos & Sons HVAC LLC is a family-owned heating and cooling contractor rooted in Boulder County since 2016, accumulating 43 five-star reviews that confirm their reputation for honest, dependable service across the region. Based in Longmont, this contractor holds over eight years of hands-on experience and serves homeowners throughout Boulder, Longmont, Erie, Lyons, Lafayette, Louisville, Niwot, Firestone, Frederick, and Hygiene, delivering furnace repair, AC tune-ups, boiler maintenance, and full system installations year-round.

What distinguishes Loos & Sons from neighboring contractors is their specialized expertise in geothermal systems and heat pump technology, areas where other local HVAC companies often lack deep knowledge. They emphasize energy-efficient solutions and provide same-day service availability, meaning homeowners facing heating failures during Boulder's unpredictable mountain winters can often receive emergency attention without waiting days. Their service menu spans traditional forced-air furnaces alongside modern mini-split configurations and geothermal loops, allowing them to serve both aging ranch-style homes and newer construction with appropriate technology.

Customer reviews describe specific scenarios where the Loos team delivered beyond expectations. When Jack Downey's boiler ruptured and flooded his basement just before a scheduled open house, John arrived at 7am, completed the repair, and had the space dry and presentable for afternoon showings, all on the same day. Brian Y's furnace had multiple potential failures across ignition and sensor components, and John methodically diagnosed each possibility before restoring blue-flame operation, avoiding an unnecessary parts replacement that a less thorough technician might have recommended.