Geothermal.contractors

Holt Plumbing & Heating is a third-generation, family-owned plumbing and HVAC contractor founded in 1947 by John F. and Edith Holt, now serving the Des Moines metro from its West Des Moines location. The company installs geothermal heat pump systems using Hydron Module — an Enertech-family ground-source brand — alongside Lennox, American Standard, Bosch, and Mitsubishi Electric equipment. NATE-certified technicians perform installation and service, and the company holds HVAC SAVE certification as a testing and balancing agent. Holt is licensed in Iowa under Master Plumbing and Mechanical Systems Contractor License 50688-CL and is BBB Accredited. With over 78 years in the Iowa trades, the company brings long-tenure experience to ground-source heat pump work. Verified active operator per https://www.holtplumbingandheating.com/geothermal-hvac/ (factcheck 2026-05-26, Opus re-audit 2026-05-27)