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Air Conditioning

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Professional AC Unit Replacement Services

When it’s time to upgrade your AC system, Ressler & Mateer is your reliable choice. We are committed to assisting you in choosing the perfect system that suits your space and budget. Our team will handle the installation and maintenance, ensuring your comfort year after year.

Moreover, Ressler & Mateer is a trusted expert in ductless cooling systems across Lancaster, PA. We will collaborate closely with you to identify the ideal ductless cooling option and take care of the installation and maintenance, allowing you to enjoy a worry-free experience.

AC Unit Installation Tips

Experience comprehensive heating and air conditioning service and installation for both residential and commercial properties across Harrisburg, Lancaster, Lebanon, Reading, West Chester, Mechanicsburg, and York, PA. Ressler & Mateer takes great pride in being recognized as the leading provider of cooling services in the region. Our commitment, dedication to service, and high-quality products are the cornerstones of our company.

Your satisfaction is our top priority whenever we undertake a project. With round-the-clock emergency service and maintenance programs designed to ensure the optimal functioning of your systems, we are always available to address any issue that may arise. Count on us to be there for you, providing reliable support and peace of mind.

Cooling Services

  • Cooling Maintenance
  • Service & Repairs
  • AC Installations
  • System Replacement
  • Geothermal
  • Ductless Systems
  • Indoor Air Quality
  • Duct Cleaning
  • Whole Home Dehumidifiers
  • Smart / Programmable Thermostats
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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.

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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.

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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.

Installing Brands You Can Trust:



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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24/7 Air Conditioning Service Availability

When the time comes to replace your AC system, Ressler & Mateer is your trusted partner for top-notch service. Our team of skilled professionals excels in guiding you towards selecting the perfect system that aligns with your specific needs and budget, prioritizing both performance and energy efficiency. Whether you have an old home, such as a farmhouse, and require the installation of ductwork or prefer the convenience of ductless units, we have you covered.

Rest assured that we will handle every aspect of the replacement process with meticulous care and attention to detail. From the initial consultation to the final installation, we strive to provide a seamless and stress-free experience, minimizing any disruption to your daily routine. Don’t hesitate to contact us today to schedule your HVAC system replacement and take the first step towards optimal comfort in your home.

Ressler and Mateer: The Air Conditioning Company for You

Ressler & Mateer is a renowned expert in home comfort, specializing in air conditioning and dehumidification solutions. We are dedicated to creating the perfect indoor environment to ensure your utmost comfort. Whether you need a new air conditioning system installation, repairs for an existing unit, or regular maintenance to keep it running smoothly, our skilled professionals have you covered. Additionally, we understand the importance of controlling humidity levels in your home. Our team can provide expert guidance and install high-quality dehumidifiers to maintain optimal comfort and prevent issues like mold and mildew. With Ressler & Mateer, you can trust that your home will be a haven of refreshing coolness and ideal humidity, enhancing your overall comfort and well-being.

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