Open Monday-Friday: 8am-5pm
16700 Sideroad 17A, Sunderland, ON L0C 1H0
FAMILY OWNED SINCE 1982
Elevating Comfort Across Durham Region, York Region, Kawartha Lakes & more!
Welcome to Harold Heating & Cooling — where innovation meets tradition in the heart of your home and business. For over 40 years, our family-owned company has been at the forefront of heating and cooling solutions, serving residential and commercial clients with unparalleled dedication.
WORKING WITH INDUSTRY LEADERS
Whether you're looking to install a new furnace in your home, a geothermal system for your business, or require emergency repairs, we're here to provide you with the best options. As a proud Carrier dealer and Smart Power supplier, we offer the most innovative and advanced products, ensuring you receive top-of-the-line technology and efficiency.
.png){kind=icon}
Our Services
WE OFFER RESIDENCIAL & COMMERCIAL SERVICES
INFLOOR HEATING
Custom-engineered in-floor radiant heating solutions. By circulating warmth directly through your flooring, these systems eliminate cold spots and airborne allergens, providing a silent, high-efficiency heating experience that transforms the comfort of your home
POWER ANYTIME, EVEN DURING OUTAGES
WITH GENERAC STANDBY SYSTEMS
A Generac standby generator protects your home and gives you peace of mind. When the power fails, you'll be ready. With automatic operation and 24/7/365 support from our Wisconsin headquarters, a Generac backup generator gives you added protection in an increasingly uncertain world.
RECIEVE UP TO $2100 IN REBATES
Save Money On All Qualifying Systems
We are committed to ensuring you receive the maximum value for your home comfort investment by staying at the forefront of 2026 rebate programs and provincial energy initiatives. Our team works directly with you to identify every available cost-saving opportunity—from federal affordability grants to local utility incentives—to ensure your project remains within budget without compromising on performance. To guarantee long-term reliability, we partner exclusively with industry-leading suppliers.
40+ Years of Service
4.5 Star Rating
24/7 Emergency Support
100% Eco-Friendly Options
REAL STORIES, REAL SATISFACTION
Hear What Our Customers Think
The service I received was exceptional. The individuals that installed my air conditioner were clean and courteous. I would highly recommend Harold's Heating.
- Bev Primrose
Excellent service and quick response. They installed a new furnace and hot water tank for me as well as perform my service. Would recommend.
Thank you to Harold’s Heating for prompt and efficient service. We really appreciated JP’s attention to detail. His customer service and diagnostic skills are exemplary!
Had Carly out today! She did a very thorough cleaning and check for furnace and fireplace. Very good at explaining and communicating what she was doing, Great job! Thanks all!