Founded in 1909, Haslett Heating & Cooling, Inc is a leader in the mechanical construction industry with a strong commitment to quality and integrity. The firm has experience in complex mechanical projects throughout central Ohio.A benefit of being in business for over 100 years is that it has given us the opportunity to develop strong partnerships with owners, engineers and suppliers from across the country. Developing these relationships has been instrumental to our success in the industrial, healthcare, pharmaceutical, educational and commercial markets.. Haslett Heating and Cooling,Inc has been a mechanical contractor since 1909. We provide installation; service,maintenance,and design build services. Ohio License 25525. We offer 24 hour emergency service!