Hvac Markham
Your #1 Choice For
We've got prestigious awards for our work
Turning up the chill factor in your home or office
Our company, ONCALL Heating & Cooling, believes that comfort is an essential requirement rather than an optional luxury. Your space’s indoor climate remains perfectly positioned whenever you need it to be – safe, comfortable, energy-efficient, no matter which season is happening outside.
- Ventilation System Maintenance
- Indoor Air Quality Testing
- Cool Craft Custom Solutions
Your Trusted Residential & Commercial HVAC Partner – Serving All of Markham
ONCALL Heating & Cooling is a licensed, bonded, and insured HVAC company that has been in business since 2005. We provide complete heating, cooling, and gas services to Markham-area homes and businesses. Whether you’re battling a frigid winter or a scorching summer, the HVAC Markham branch has the perfect solution.
Complete Residential and Commercial HVAC Services in Markham
At ONCALL Heating & Cooling, we provide a full spectrum of heating, cooling, ventilation, and gas services to residential homes, businesses, offices, and commercial properties across Markham. Whether you need an air conditioner repair, installation, a custom HVAC setup or simple furnace repair for your commercial facility, our AC and furnace repair Markham experts are here to serve.
We approach every project with precision, safety, and attention to detail, ensuring that our work meets local building codes, energy standards, and your expectations. Our AC repair Markham team is experienced in handling both small-scale and large-scale projects and can manage everything from equipment upgrades to new HVAC system designs.
Licensed & Insured
Our licensed HVAC technicians and gas fitters are trained to handle all types of heating and cooling systems, including modern energy-efficient models, rooftop units, and multi-zone configurations. We follow strict safety guidelines and ensure that every member of our team is professionally certified and up to date with Markham’s HVAC compliance standards.
All our services are performed by fully licensed, bonded, and insured technicians. Whether you’re replacing an old furnace, installing a ductless air conditioner, or setting up HVAC systems for a new commercial site, ONCALL Heating & Cooling, AC repair Markham team delivers excellence with full regulatory compliance and safety-first practices.
Reliable, On-Time HVAC Project Management
At On Call Heating & Cooling, we take your comfort and deadlines seriously. Throughout every stage of your HVAC project, we provide regular progress updates, transparent communication, and expert recommendations—ensuring a seamless experience for homeowners and businesses alike. We’re committed to meeting your heating and cooling needs on time and within your budget, using the latest tools, practices, and energy-efficient technologies.
Our Residential HVAC Services in Markham Include:
- Heating Services: Furnace repairs, installations, seasonal tune-ups, and efficient heating solutions
- Cooling Services: Air conditioner installations, repairs, and central cooling systems
- Water Heater Services: Tank and tankless systems installed, maintained, and repaired
- Boiler Services: Full boiler diagnostics, maintenance, and replacement
- Heat Pump Services: Energy-saving hybrid systems for year-round comfort
- Ductwork Services: Custom duct design, sealing, cleaning, and airflow optimization.
Our Commercial HVAC Services in Markham Include:
- Commercial Maintenance Plans
- Commercial HVAC Installations
- Gas Furnace Repairs & Installations
- Humidifier Installations
- Gas Stove Hook-Ups
- Gas Dryer Hook-Ups
- Gas Fireplace Installations
- Central Air Conditioning Systems
- Rooftop Unit Installations and Repairs
Our Services Cover a Wide Range of Commercial Properties:
- Office Buildings
- Clinics & Medical Offices
- Warehouses
- Retail Stores & Shopping Units
- Factories & Workshops
- Apartment Buildings
- Condominiums
- Hair & Nail Salons
- Commercial Garages & Underground Parking
- Restaurants, Cafes & Commercial Kitchens
Other Services
All Service Locations in Canada
The On Call Heating & Cooling Difference
- We respond quickly to your calls and service requests
- We respect your schedule and provide flexible service hours
- We respect your property and workspace—leaving it clean and safe
- We work within your budget and offer competitive, transparent pricing
- We seek opportunities for cost-savings and energy efficiency throughout the project
We’ve earned the trust of hundreds of customers across Markham through our dedication to doing the job right the first time—with comfort, safety, and performance at the core of everything we do.
Need Heating or Cooling Service in Markham? We’re On Call.
Whether it’s time for an upgrade, emergency repair, or new installation, ONCALL Heating & Cooling’s furnace and air conditioner repair Markham team is ready to help. We’re proud to serve all of Markham and nearby areas with HVAC solutions that last.
Call us today to schedule a free consultation.
Experience Markham’s trusted HVAC service—ONCALL, always on time.
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