Available in Harrisburg, Lancaster, Lebanon, Reading, West Chester, Mechanicsburg and York, PA

Ressler & Mateer is proud to be considered the premier provider of heating and cooling services in the region. We deliver an unparalleled level of service and support, guided by the values that founded this company – commitment, dedication to service, and quality products.

Interested in a new heating system? Check out our specials

Replacing your system

When the time comes to replace your HVAC system, you can count on Ressler & Mateer. We’ll help you select the optimal system for your space and budget – then we’ll install it and maintain it, year after year.

Ressler & Mateer also specializes in ductless heating and cooling systems throughout Lancaster, PA. We will work with you to find the best ductless heating and cooling systems option – and even install and maintain it, leaving you worry-free!

Service & Maintenance

Whenever we show up for a job, we guarantee your satisfaction. With 24/7 emergency service and maintenance programs to keep your systems running smoothly, we’re always there for you, no matter the issue.


The foundation of our business is, and always has been, quality customer service. We don’t just stand by our work – we stand with our clients. This is why, on top of any manufacturer warranties, we guarantee all our workmanship and labor for one full year.

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Your comfort is our priority. Ressler & Mateer offers top-quality products backed by outstanding service to keep you comfortable, however low the temperatures may dip. We work with the best companies in the industry – here’s a look at our partners.

air conditioning

Our company has extensive capabilities in both commercial and residential air conditioning. We provide innovative systems with a reputation for dependability and superior service life.


An advanced geothermal heat pump system harnesses the energy generated and stored inside the earth. Geothermal is a sustainable, efficient, eco-friendly choice for heating and cooling for your facility.

hear from our

Just had another great experience with Ressler & Mateer. They installed units in our first house and we've continued to use them since moving to a new house. Today was the first time we've need A/C service and it was top -notch work as always. Ed is the best! He was on-time, worked quickly and gave me some good tips on keeping the unit running. When you find a company you know you can trust, you stick with them. And that's why we stick with Ressler & Mateer. — Andrew Wagner - Quarryville, PA
Emergency? Call for 24/7 Service: 717-859-2025

Ressler & Mateer

Ressler & Mateer is open and implementing safety measures to help protect our customers and employees from the spread of COVID-19.