Best HVAC contractor in Cupertino for SameDay Service

United HVAC, Plumbing & Electrical is a multi-trade contractor based in Cupertino and San Jose, serving the Bay Area including San Jose, Santa Clara, Los Altos Hills, Saratoga, and Palo Alto. The plumbing side covers water heaters — traditional tank, tankless, and heat pump models — with seismic-compliant gas heater installs, plus drain cleaning, sewer and water leak work, and general repairs. The HVAC and electrical divisions add heat pump systems, panel upgrades, 240-volt prewiring, and full-home electrification with rebate assistance. Hours run 7 AM to 10 PM daily, with same-day and emergency coverage advertised. Named techs include Bryan, Manuel, Anton, Cristopher Villa, and Pasha. Positive accounts describe flat-rate pricing that gave peace of mind when jobs ran long, skilled conduit routing on electrification projects, and fast kitchen drain fixes. A strongly negative account describes a water heater that failed under two years after installation with poor after-sales scheduling — a genuine counterweight to the praise. The honest reading: a large operation with real technical capability and a service record that varies by job and technician. This is a fit for homeowners planning bundled work — a water heater upgrade alongside a panel upgrade, or a heat pump plus plumbing rework — where one contractor across trades avoids coordination headaches. The electrification and rebate experience suits older Bay Area homes moving off gas. For anyone comparing, the flat-rate pricing and seismic-compliant installs are concrete positives; the mixed after-sales accounts suggest confirming warranty and response commitments in writing before signing.