ESI HEATING & COOLING Santa Clara. We pride ourselves on being a reliable HVAC company in Santa Clara with expertise, experience, and passion for providing excellence in HVAC services. We offer a personal approach to our clients because we understand that every HVAC problem is different. Our HVAC technicians always strive to make your experience informative, easy, and pleasant. We also offer other services such as rodent proofing, insulation, air duct cleaning, sanitation services, and crawlspace services.