# Boiler Installation Markham | Hydronic & Radiant URL: https://boilerinstallationtoronto.ca/service-areas/markham/ ![](/images/misc/service-van-parked-in-a-residential-gta-driveway-a.webp) Toronto Boiler Installation [/ →](/) # Boiler Installation Markham: High-Efficiency, Combi, Replacement and Hydronic Heating Service Across Unionville and Cornell Last updated: September 19, 2026 Boiler installation in Markham means larger heating loads and better distribution. Unionville, Cornell, and Markham Village custom homes across the L3P to L3S postal codes run hydronic and in-floor radiant systems where control faults are as common as equipment failure. **Markham Cost Anchor:** Markham hydronic and combi systems run $5,500-$9,500 CAD for a swap; radiant work scales with zone count. Combi boiler installation runs $4,500 to $8,500 CAD and a 95%+ AFUE condensing unit $6,500 to $12,000 CAD, with combined Enbridge and federal rebates offsetting up to $11,500 CAD. Call (647) 254-9788 [tel:+16472549788 →](tel:+16472549788) Request Written Installation Quote [/contact/ →](/contact/) - L3P-L3S - Same-day GTA dispatch, 4-hour cold-snap response - TSSA G1/G2 Licensed Crew - Unionville - Cornell - Markham Village - 5-Star Customer Satisfaction - Same-Day GTA Emergency Dispatch - 22 Years of Boiler Installation Experience - Written Workmanship Warranty Common Objections ## What Actually Stops GTA Homeowners From Replacing an Aging Boiler Four objections come up on almost every call. Here is the straight answer to each, with the CAD numbers attached. ### 1\. “The quote is huge, I am being oversold” A high-efficiency condensing swap runs $6,500 to $12,000 CAD because it includes a new condensate line, PVC flue rework, near-boiler piping, expansion tank, zone controls, and the TSSA permit. Every line item appears on the quote in CAD. Combined Enbridge and federal rebates offset up to $11,500 CAD. ### 2\. “You cannot tell if the technician is really licensed” Ontario requires TSSA G1 or G2 certification for gas boiler work, plus CSA B51 for large-BTU pressure vessels. Certificate numbers appear on every invoice and TSSA permit numbers appear on completed work. ### 3\. “Nobody publishes the price” Our four CAD scope bands are published on this page: diagnostic $99 to $249, standard repair $200 to $1,200, major repair $1,200 to $3,500, and full combi installation $4,500 to $8,500. High-efficiency condensing runs $6,500 to $12,000 CAD. ### 4\. “The boiler is 25 years old, repair or replace?” Cast iron lasts 30 to 50 years but drops to 60 to 70 percent efficiency by year 25. A modern 95% AFUE unit cuts natural gas bills 25 to 35 percent, qualifies for up to $11,500 CAD in rebates, and pays back in 6 to 10 years. You get a written repair-versus-replace on every diagnostic. Talk it through with a licensed technician [tel:+16472549788 →](tel:+16472549788) Local Housing Stock ## What Boilers in Markham Actually Look Like Newer custom homes with hydronic and in-floor radiant systems on larger heating loads. **Typical failure pattern:** Control or circulator faults on higher-end hydronic and radiant distribution. **Postal codes served:** L3P-L3S. Covering Unionville, Cornell, Markham Village and the surrounding neighbourhoods, under City of Markham. Markham hydronic and combi systems run $5,500-$9,500 CAD for a swap; radiant work scales with zone count. - Same-day GTA dispatch, 4-hour cold-snap response - 22 years serving Markham and York Region - TSSA G1/G2 technicians covering Unionville, Cornell and Markham Village - 4-hour cold-snap response ![Basement mechanical room with a condensing boiler in a Markham home](/images/misc/older-brick-home-basement-mechanical-room-with-cas.webp) ## Our Boiler Services in Markham Boiler installation in Markham means larger heating loads and better distribution. Unionville, Cornell, and Markham Village custom homes across the L3P to L3S postal codes run hydronic and in-floor radiant systems where control faults are as common as equipment failure. ![Wall-mounted 95%+ AFUE condensing boiler installed in a Toronto basement with copper near-boiler piping and PVC flue](/images/misc/wall-mounted-95-percent-afue-condensing-boiler-new.webp) Most Requested ### High-Efficiency Condensing Boiler Installation Toronto 95%+ AFUE condensing boiler installation with 316L stainless heat exchangers, PVC side-wall venting, and full Enbridge plus Canada Greener Homes rebate coordination across Toronto and the GTA. $6,500 - $12,000 CAD [High-Efficiency Condensing Boiler Installation Toronto →](/high-efficiency-boiler-installation-toronto/) ![Wall-mounted combi boiler installed in a compact Toronto utility room with isolation valves and domestic hot water piping](/images/misc/compact-wall-mounted-combi-boiler-installed-in-a-s.webp) Space Saver ### Combi Boiler Installation Toronto Compact wall-mounted combi boilers delivering uninterrupted heating and on-demand domestic hot water, sized by GPM for Toronto homes and fitted with descaling valves for GTA hard water. $4,500 - $8,500 CAD [Combi Boiler Installation Toronto →](/combi-boiler-installation-toronto/) ![Old cast iron sectional boiler being removed beside a newly installed condensing unit in a Toronto basement](/images/misc/old-cast-iron-sectional-boiler-being-broken-down-f.webp) ### Boiler Replacement Toronto End-of-life gas boiler replacement for 15 to 40 year old systems, including cast iron conversions, chimney liner de-commissioning, gas line sizing, and disposal across Toronto and the GTA. $8,500 - $14,500 CAD [Boiler Replacement Toronto →](/boiler-replacement-toronto/) ![Cascading commercial condensing boilers in a Toronto mid-rise mechanical room with common venting header](/images/misc/two-cascading-commercial-condensing-boilers-mounte.webp) ### Commercial Boiler Installation Toronto Rooftop and basement commercial boiler installation for retail plazas, restaurants, offices, and mid-rise condos, built to CSA B51 pressure vessel code and ASHRAE 90.1 efficiency standards. $8,500 - $18,000 CAD [Commercial Boiler Installation Toronto →](/commercial-boiler-installation-toronto/) ![Restored cast iron column radiator with a thermostatic radiator valve in a pre-war Toronto living room](/images/misc/restored-cast-iron-column-radiator-with-a-thermost.webp) ### Hydronic Heating and Radiator Installation Toronto Hydronic distribution design and radiator installation: cast iron column radiators, baseboard convectors, thermostatic radiator valves, and oxygen-barrier PEX manifolds, balanced and air-eliminated. $3,500 - $12,000 CAD [Hydronic Heating and Radiator Installation Toronto →](/hydronic-heating-installation-toronto/) ![Oxygen-barrier PEX radiant loops laid across a Toronto basement slab before pour, with the manifold on the wall behind](/images/misc/oxygen-barrier-pex-radiant-loops-stapled-to-insula.webp) ### In-Floor Radiant Heating Toronto Hydronic in-floor radiant heating retrofits and new-build installs with PEX loop layout, mixing valves, and return-water protection across four zones in Toronto and GTA homes. $8,000 - $20,000 CAD [In-Floor Radiant Heating Toronto →](/in-floor-radiant-heating-toronto/) ![Technician using a digital flue gas analyser during an annual 12-point boiler tune-up in Toronto](/images/misc/technician-holding-a-digital-flue-gas-analyser-wit.webp) Best Value ### Boiler Maintenance and Annual Service Toronto Annual 12-point boiler tune-up with digital combustion analysis, expansion tank pre-charge, water pH and glycol testing, and pressure relief valve testing to keep warranties valid. $199 - $349 CAD [Boiler Maintenance and Annual Service Toronto →](/boiler-maintenance-toronto/) ![Technician testing an ignition control board inside an opened Toronto boiler casing](/images/misc/technician-with-a-multimeter-testing-an-ignition-c.webp) ### Boiler Repair Toronto Standard and major boiler repair across ignition, pressure, and heat exchanger faults, with published CAD bands and a written repair-versus-replace analysis on every diagnostic. $200 - $3,500 CAD [Boiler Repair Toronto →](/boiler-repair-toronto/) ![Technician diagnosing a failed boiler during an emergency no-heat call in a Toronto basement](/images/misc/technician-with-a-work-light-and-tool-case-diagnos.webp) 24/7 Dispatch ### Emergency Boiler Repair Toronto 24/7 emergency boiler repair with same-day GTA dispatch and 4-hour cold-snap response for no-heat, red-tag, ignition-lockout, and frozen condensate failures. $199 - $349 CAD [Emergency Boiler Repair Toronto →](/emergency-boiler-repair-toronto/) Why Choose Us ## Why Markham Trusts Our Hydronic Work - 22 Years of Boiler Installation Experience across Toronto and the GTA - Controls diagnosed before equipment, so you are not sold a boiler you do not need - In-floor radiant zone design, mixing valves and return-water protection - Combi and condensing swaps $5,500 to $9,500 CAD, radiant priced by zone count - TSSA G1 and G2 licensed, Manual J heat load on every installation - Enbridge and Canada Greener Homes rebate paperwork filed for you The Framework ## How Our Markham Boiler Installation Works, 6 Steps From the first call to the rebate cheque, here is exactly what happens and in what order. 1. 1 ### Site assessment Postal code, home age, distribution type, existing AFUE, and heating load in BTU per square foot. Same-day or next-morning visit. 2. 2 ### Manual J heat load and sizing Written heat load with boiler capacity sized to the actual home load. No oversizing, which is what causes short cycling. 3. 3 ### Written quote, three options Combi, split system, and high-efficiency retrofit priced in CAD with parts, labour, permits, disposal, and rebate offset per option. 4. 4 ### TSSA permit and scheduling Ontario Building Code Part 6 compliance verified. Installation within 3 to 7 business days standard, 24 to 48 hours on emergencies. 5. 5 ### Installation and commissioning Boiler installed to CSA B51, near-boiler piping to ASHRAE 90.1, condensate neutralised, combustion analysis with a CO monitor, system purged and rebalanced. 6. 6 ### Verification and rebate filing TSSA inspection where required, warranty registration filed, Enbridge and Canada Greener Homes paperwork submitted, written workmanship warranty issued. ## Need a boiler quote in Markham? Published CAD pricing, TSSA-licensed technicians, and same-day dispatch across the whole coverage area. (647) 254-9788 [tel:+16472549788 →](tel:+16472549788) Get CAD Quote [/contact/ →](/contact/) ## Reaching Unionville, Cornell and Markham Village Markham dispatch runs on Highway 407, Highway 404, and Highway 7 with Main Street Unionville, Kennedy Road, and Ninth Line as the local connectors. Cornell sits east off Highway 7 near the hospital, Unionville is central, and Markham Village runs along Main Street North. Same-day dispatch covers the L3P to L3S postal codes. Markham jobs take longer on site than a straight combi swap because the systems are larger. A custom home with four radiant zones, a mixing station, and an indirect tank is not diagnosed in fifteen minutes. We budget the assessment accordingly rather than rushing it and guessing at the fault. Cold-snap response is four hours. On radiant systems the priority on arrival is protecting the slab loops and the mixing valve, not just restarting the burner, because a hard restart at full supply temperature on a cold slab is how a good radiant system gets damaged. ## Markham Systems Are Bigger, and Controls Fail Before Boilers Do Unionville and Cornell custom homes run heating loads well above the GTA average, often with three to five zones split between in-floor radiant on the lower level and hydronic baseboard or panel radiators above. Markham Village has a mix, with some older homes on conventional hot water distribution and newer infill on radiant. On systems this size, the boiler is rarely the first thing to fail. The outdoor reset sensor drifts, a zone valve actuator sticks, the mixing valve loses its setpoint, or a circulator cartridge seizes on one loop while the rest of the house still heats. The symptom looks like a failing boiler, which is why so many Markham homeowners have been quoted a replacement they did not need. We diagnose the control layer first. That means checking the outdoor reset curve, the zone synchronisation, the delta T across each loop, and the mixing valve setpoint before anyone talks about a new boiler. When the equipment genuinely is at end of life, the replacement is sized from a Manual J heat load and the existing distribution is rebalanced rather than left as-is. - Four-zone in-floor radiant diagnosis and loop balancing - Outdoor reset curve setup and zone synchronisation - Mixing valve and return-water temperature protection for slab loops - Variable speed ECM circulator upgrades on multi-zone systems - Manual J heat load sizing on replacement, no oversizing Customer Feedback ## What Markham Customers Say > Our Unionville custom home has in-floor radiant. They added zone controls and outdoor reset for $2,300 CAD and run-time dropped noticeably. Vivian C. Unionville 5-Star Customer Satisfaction > Cornell home needed a radiant zone added during a reno. Clean loop layout and manifold for $12,600 CAD. Nathan W. Cornell Top-Rated Contractor > Markham Village boiler at end of life. New high-efficiency unit for $8,200 CAD with rebate coordination. Laila F. Markham Village Trusted by Homeowners and Businesses Get a Quote ## Tell Us What Your Boiler Is Doing Short form, no gatekeeping. A TSSA-licensed technician follows up with a written CAD quote for Markham, and the diagnostic fee comes off the invoice when you authorise the work on the same visit. - Four published CAD scope bands, never gated - Same-day GTA dispatch, 4-hour cold-snap response - Enbridge and Canada Greener Homes paperwork filed for you - Written workmanship warranty on labour ### Thanks, we have your message. A TSSA-licensed technician follows up within one business day. ## Request a Written Installation Quote Send the details and a TSSA-licensed technician follows up with an itemised CAD quote. No email address required from us, no quote gating from you. Local Questions ## Boiler Installation Markham: Frequently Asked Questions ### How fast can you reach Unionville or Cornell? Same-day dispatch covers the L3P to L3S postal codes and cold-snap no-heat calls get a technician within four hours. Crews route on Highway 407, Highway 404, and Highway 7. ### What does boiler work cost in Markham? Markham hydronic and combi systems run $5,500 to $9,500 CAD for a swap and $6,500 to $12,000 CAD for a standard high-efficiency condensing installation. In-floor radiant installation is $8,000 to $20,000 CAD depending on zone count. Control upgrades such as aquastats and zone controls are $250 to $650 CAD. ### One zone is cold but the rest of the house is fine. Is my boiler failing? Almost certainly not. A single cold zone points at a stuck zone valve actuator, a seized circulator cartridge on that loop, or air trapped in the loop. We check delta T across each loop before discussing equipment, which is why a lot of Markham calls end as a repair rather than a replacement. ### Can you add a radiant zone during a renovation? Yes. We lay out oxygen-barrier PEX loops, set the manifold, size the mixing valve, and integrate the new zone into the existing control strategy so it does not fight the rest of the system. Radiant work is priced by zone count and subfloor type. ### What is outdoor reset and is it worth it? Outdoor reset lowers the boiler supply temperature as the outdoor temperature rises, so the unit spends more of the season condensing instead of firing at full temperature. On a Markham-sized hydronic load it is one of three control upgrades that typically pay back in under two years. ### Do you size the replacement or just match what is there? We run a Manual J heat load and size to the actual load. Matching an existing oversized boiler simply repeats the short-cycling problem, which shortens equipment life and wastes gas. ### Do you cover Milliken, Thornhill and Greensborough? Yes. The full L3P to L3S range is covered on the same day schedule, including Milliken, Thornhill, Greensborough, Berczy Village, and Angus Glen. ### How often should a multi-zone hydronic system be serviced? Annually, before the heating season. On multi-zone systems the tune-up also covers zone synchronisation, circulator check, mixing valve setpoint, and glycol concentration where a slab loop is present. The 12-point service is $199 to $349 CAD. ### Still have a question about your boiler? Talk to a TSSA-licensed technician. Same-day GTA dispatch, 4-hour cold-snap response. (647) 254-9788 [tel:+16472549788 →](tel:+16472549788) Request Written Installation Quote [/contact/ →](/contact/) ## Boiler Service Coverage in Markham Get Directions [https://www.google.com/maps/dir/?api=1&destination=43.8561,-79.3370 →](https://www.google.com/maps/dir/?api=1&destination=43.8561,-79.3370) ## We Also Cover These Areas Near Markham Boiler Installation Richmond HillRichmond Hill hydronic and combi systems run $5,500-$9,500 CAD for a swap. View Richmond Hill page [/service-areas/richmond-hill/ →](/service-areas/richmond-hill/) Boiler Installation ScarboroughScarborough retrofits run $8,500-$14,500 CAD for older cast iron, $5,500-$9,500 CAD for newer combi swaps. View Scarborough page [/service-areas/scarborough/ →](/service-areas/scarborough/) Boiler Installation North YorkNorth York retrofits run $8,500-$14,500 CAD for older cast iron, $5,500-$9,500 CAD for newer combi swaps. View North York page [/service-areas/north-york/ →](/service-areas/north-york/) ![](/images/misc/tssa-licensed-technician-closing-the-front-panel-o.webp) Same-Day Emergency Dispatch, 24/7 Cold Snap Response ## Book Boiler Installation in Markham Same-day dispatch with a four hour cold-snap response, and an itemised CAD quote before any work starts. Call (647) 254-9788 [tel:+16472549788 →](tel:+16472549788) Request Written Installation Quote [/contact/ →](/contact/) - Written workmanship warranty - Published CAD pricing, no quote gating - TSSA G1/G2 licensed technicians