Diagnose, repair, and start up chilled water plants (air-cooled chillers, pumps, VFDs, hydronic loops), custom and commercial-grade air handlers and fan coils (including AAON), VRF (Mitsubishi Electric CITY MULTI, LG Multi V), Trane variable-speed communicating systems, whole-house dedicated dehumidifiers, ERVs, wine room and art storage cooling, indoor pool dehumidification, and walk-in refrigeration using manufacturer procedures and diagnostic software. Lead dehumidification and building pressurization work: diagnose humidity, indoor air quality, and pressure problems using dew point, wet bulb, and moisture readings; measure supply, return, and outdoor air; and correct issues with dedicated dehumidification, ERV and fresh air, high-MERV and HEPA filtration, UV, duct leakage repair, and condensate management.