# Commercial RTU Repair Toronto | Rooftop Units Toronto Pros > Commercial rooftop unit repair Toronto by Rooftop Units Toronto Pros. Red Seal HVAC-R + CRE-ticketed. 24-hour written quote. Save on Energy rebate filed. URL: https://rooftopunitstoronto.ca/commercial-rooftop-unit-repair-toronto/ ![Open packaged rooftop unit compressor compartment on a Toronto commercial roof during a repair](/images/misc/red-seal-technician-tools-laid-beside-an-open-pack.webp) Primary Hub | Red Seal Diagnostics # Commercial Rooftop Unit Repair in Toronto, Diagnosed Right the First Time Last updated: October 24, 2026 Red Seal diagnostics for packaged RTUs: compressors, refrigerant, economizers, controls. Written tally before work starts. - No cooling - No heat - Short cycling - Iced evaporator - Economizer stuck - Refrigerant leak Book a Site Assessment [/contact/ →](/contact/) View Pricing [#pricing →](#pricing) 24-Hour Written Quote From $275 per repair (diagnostic to compressor) - Parts, labour, crane, permit + HST on one line - 2-4 hr on-roof emergency response, GTA core - Save on Energy rebate filed on qualifying work Red Seal HVAC-RTSSA G1 + G2ESA + CRE$5M + WSIB 24/7 Dispatch (437) TBD [tel:+14370000000 →](tel:+14370000000) - 24-Hour Written Quote (not a sales pitch) - 24/7 Emergency RTU Dispatch (2-4 hr on-roof GTA core) - Red Seal HVAC-R + TSSA + ESA + CRE Chiller - $5M Liability + WSIB + COI in 24 Hours - Save on Energy Rebate Filed on Your Behalf 1,800+ GTA installs 97% Uptime 2-4 hr On-roof, GTA core 48 Sites under contract Symptoms first ## Is Your Equipment Showing These Signs? No cooling, no heat, short cycling, iced coils, a stuck economizer or a tripped breaker: our Red Seal HVAC-R techs test electrical, refrigerant, airflow and controls before any part is ordered. You get a written tally before work starts, and a clear repair-vs-replacement recommendation when the unit is old or keeps failing. - No cooling - No heat - Short cycling - Iced evaporator - Economizer stuck - Refrigerant leak - Failed capacitor - Blown fan motor Seeing one of these? Book a site assessment [/contact/ →](/contact/) or call dispatch for a 2-4 hour on-roof visit in the GTA core. ## What Is Going Wrong With Your Rooftop Unit? Commercial rooftop unit repair starts with the symptom, not the part. A packaged RTU that will not cool, will not heat, short cycles, ices its evaporator or trips its breaker is telling you something specific. The job is to find out what before anyone orders a compressor. Most of the commercial rooftop units we are called to in Toronto [/ →](/) have one of four problems: an electrical failure (contactor, capacitor, fan motor, wiring), a refrigerant problem (leak, restriction, failed TXV), an airflow problem (dirty filters, slipping belts, iced coil) or a controls problem (economizer, thermostat, board or sensor). Those four groups explain almost every no-cool call on a GTA roof. The trouble is that the symptoms overlap. An iced evaporator can be low charge, low airflow or a failed defrost control. A compressor that will not start can be a dead compressor, or it can be a $40 capacitor. That is why residential-trained techs often swap expensive parts on commercial equipment: they are guessing. ## How Our Red Seal Techs Diagnose a Commercial RTU Our leads hold Red Seal 313A Refrigeration and Air Conditioning Mechanic certification plus TSSA G1 gas and ESA electrical tickets. Every diagnostic follows the same order, so nothing is skipped: 1. **Electrical first.** Line voltage, control voltage, contactor condition and capacitor values are measured. Compressor windings get a megger winding test before anyone calls a compressor dead. 2. **Refrigerant second.** Gauges go on and we read superheat and subcooling against the manufacturer chart. That tells us whether the TXV, the charge or a restriction is the issue. 3. **Airflow third.** Filters, belts, blower speed and static pressure are checked, because a starved coil will look like a refrigerant fault. 4. **Controls last.** We pull fault codes from the unit controller, check the thermostat or BAS signal, and test the economizer enthalpy sensor, actuator and damper linkage. Only then do you get the written tally: failed parts, labour hours, timeline and total, with HST on its own line. > **Why the order matters** > > On our Dundas West job, a 7-ton Lennox LCG had already been condemned by another contractor. The megger test showed one grounded compressor in an otherwise sound unit. The repair was $3,850 all-in, a fraction of a replacement. ## Types of Commercial RTU Repair We Handle ### Compressor repair and replacement Scroll compressors in 3-25 ton packaged units fail from overheating, liquid floodback, electrical faults or plain age. A compressor repair or replacement runs $2,400-$5,600 depending on tonnage and roof access. We braze in a new filter drier, pressure test with nitrogen, pull a deep vacuum and recharge by weight, then log startup readings. ### Refrigerant leak search and recharge Leak search and recharge runs $850-$2,800, with R-410A billed at $85/lb. We use electronic detection, bubble testing and nitrogen standing pressure to find the leak, then repair it before recharging. Topping up a leaking unit without a repair is money lost, and we will not do it on a commercial system without telling you so in writing. ### Economizer and controls repair Economizer and controls diagnostics run $450-$900. Stuck dampers, failed actuators, drifting enthalpy sensors and bad changeover setpoints waste energy all year and can freeze coils in winter. We also repair Honeywell, Johnson Controls and OEM unit controllers and fix thermostat and BAS communication faults. ### Fans, motors, belts and electrical Blown condenser fan motors, worn blower belts, burnt contactors and failed capacitors are the most common same-day fixes. Our vans carry the parts for Lennox, Carrier, York, Trane and Daikin units, so most of these repairs finish on the first visit. ### Gas heat section Winter calls are usually flame sensors, igniters, inducer motors, gas valves or limit switches. Our TSSA G1 and G2 techs test combustion and inspect the heat exchanger. A cracked heat exchanger is a safety issue and the unit will be locked out until it is fixed or replaced. ## When Do You Need RTU Repair Instead of Maintenance? Call for repair when the unit stops doing its job: no cooling, no heat, tripped breakers, burning smells, water leaking into the space, loud grinding or banging, or a space that will not hold setpoint. Book commercial rooftop unit maintenance [/commercial-rooftop-unit-maintenance-toronto/ →](/commercial-rooftop-unit-maintenance-toronto/) when the unit runs but hydro bills are rising, belts squeal or the same small faults keep coming back. Quarterly maintenance prevents most of the repairs on this page. If the unit is down after hours or on a weekend and tenants are affected, go straight to emergency rooftop unit repair [/emergency-rooftop-unit-repair-toronto/ →](/emergency-rooftop-unit-repair-toronto/) . Dispatch answers 24/7 and a tech is on the roof in 2-4 hours across the GTA core. ## Repair or Replace? The Math We Put on Paper Every tally on an older unit includes a repair-vs-replacement note. We weigh four things: | Factor | Lean toward repair | Lean toward replacement | | --- | --- | --- | | Unit age | Under 12 years | Over 15-20 years | | Refrigerant | R-410A or newer | R-22 with an active leak | | Repair size | Under 30% of a new unit | Second compressor or failed heat exchanger | | Repair history | First major failure | Repeat failures in 2-3 years | When replacement makes more sense, the note shows the installed range for the right tonnage (3-5 ton $9,500-$16K, 10 ton $18K-$34K, 15-20 ton $32K-$58K) and the Save on Energy rebate that would apply. See commercial rooftop unit replacement [/commercial-rooftop-unit-replacement-toronto/ →](/commercial-rooftop-unit-replacement-toronto/) for how we handle curb adapters and crane day. ## Repair Calls Across Toronto and the GTA We repair RTUs on retail plazas in King West and The Queensway, office buildings along the Yonge corridor in North York [/service-areas/north-york/ →](/service-areas/north-york/) , clinics in Davisville and Leaside, restaurants in Liberty Village and industrial roofs in Mississauga [/service-areas/mississauga/ →](/service-areas/mississauga/) and Scarborough. Downtown work often needs a lift or hoisting plan for parts, and we handle that as part of the job. ## Why DIY or a Residential Tech Costs More Commercial RTUs run three-phase power, multi-stage compressors, economizers and gas sections in one cabinet. A wrong guess on a 10-ton unit can mean a $5,000 compressor that did not need replacing, or a cracked heat exchanger that was missed. Repairs on refrigerant circuits also legally require a licensed technician in Ontario. A proper commercial diagnostic costs $275-$425 and usually saves far more than that. Published pricing ## How Much Does RTU Repair Cost in Toronto? Ranges from recent GTA jobs. Your written quote lands within 24 hours with parts, labour, crane, permit and HST on one line, and rebate-net pricing where the work qualifies. Labour $185/hr business, $280/hr after-hours, $425/hr weekend. R-410A $85/lb. 25/50/25 payment on installs: 25% at order, 50% on install day, 25% on commissioning sign-off. Net-30 for commercial and PM accounts. See all pricing [/pricing/ →](/pricing/) . ### RTU Repair pricing CAD + HST | Service | Price | Timeline | | --- | --- | --- | | RTU diagnostic (business hr) | $275-$425 | Same day | | RTU after-hours / weekend | $425-$650 | 2-4 hr | | Compressor repair / replace | $2,400-$5,600 | 1-2 days | | Refrigerant leak + recharge | $850-$2,800 | Same-next day | | Economizer + controls diag | $450-$900 | Same day | Free tools ## Try Our Free Commercial HVAC Service Finder Two minutes, no email required. Results show on screen first. ### Commercial HVAC Service Finder Answer five short questions to find out whether you need emergency repair, replacement, maintenance or central plant service. Take the quiz [Commercial HVAC Service Finder →](/tools/hvac-service-finder/) Case study | Dundas West, Toronto | Dundas St W retail strip ## 7-ton Lennox LCG compressor replacement on Dundas West A retail tenant on Dundas West lost cooling in late spring. A previous contractor had already quoted a full unit replacement. Our tech meggered the compressor windings, confirmed a grounded compressor on an otherwise sound 7-ton Lennox LCG, and wrote up the repair before touching anything. New compressor, filter drier, nitrogen pressure test, evacuation and recharge were done the next morning. Equipment Lennox LCG 7-ton packaged RTU Size 7 tons Turnaround Next morning Price $3,850 all-in Why property teams pick us ## Why Choose Rooftop Units Toronto Pros for RTU Repair? ### Commercial-only techs Red Seal 313A HVAC-R leads who work on packaged RTUs every day, not residential furnaces. Economizer logic and multi-stage controls are routine work. ### Tally before tools Every repair starts with a written tally. No surprise invoice, no vague package, no parts swapped to find the fault. ### OEM parts on the van Lennox, Carrier, York, Trane and Daikin parts stocked, so most failures are fixed on the first visit. ### Honest repair-vs-replace When a 17-year-old unit needs its second compressor, we show the math for replacement and the Save on Energy rebate before you spend. ### Licensed for the whole unit TSSA G1 and G2 for the gas section, ESA for electrical, Red Seal for refrigeration. One crew covers every part of the cabinet. ### PM-ready paperwork COI in 24 hours, WSIB clearance, Net-30 terms and a written service report you can attach to the work order. What to expect ## How Does Our RTU Repair Work? 1. 01 ### Dispatch + triage Dispatch confirms unit count, symptoms and roof access. Business-hours visits are same day; after-hours calls get a 30-minute dispatch window. 2. 02 ### Full diagnostic Electrical, refrigerant, airflow and controls are tested in that order. Windings are meggered before anyone condemns a compressor. 3. 03 ### Written tally You get parts, labour and timeline on paper before work starts, plus a repair-vs-replace note when the unit is old or keeps failing. 4. 04 ### Repair with OEM parts Most contactors, capacitors, motors and sensors are on the van. Compressors and coils are sourced same or next day from GTA stock. 5. 05 ### Startup readings Superheat, subcooling, amp draw and supply air temperature are logged and left with you, so the next tech starts from facts. Field photos ## Our RTU Repair Work Recent GTA rooftops and mechanical rooms. Click any photo to enlarge. ### Before + After ![Burnt compressor terminals in a failed commercial RTU](/images/cards/burnt-out-compressor-terminals-and-oil-stained-com.webp) Before ![RTU compressor compartment after repair with new compressor and filter drier](/images/cards/same-rooftop-unit-compartment-after-repair-with-ne.webp) After Dundas West, 7-ton Lennox LCG: compressor replacement, $3,850 all-in, written tally before work. Client Records ## What Clients Say About Our RTU Repair > "Our King West retail plaza had three RTUs down over a long weekend. First unit cooling by Saturday noon, all three up before Monday open. Written diagnostic same day." PSPriya S.PM, King West retail > "Another company told us the whole unit had to go. They tested the compressor, showed us it was the only failed part and had us cooling the next morning for $3,850." AGAnthony G.Store operations, Dundas West > "The economizer on our Leaside office RTU was stuck open all winter. They found a failed actuator and a bad enthalpy sensor in one visit and sent the report the same afternoon." MBMichelle B.Property manager, Leaside > "We get a written tally every time before any work starts. That alone made them our only rooftop contractor for three plazas on The Queensway." CNChris N.Facility coordinator, Etobicoke > "Short cycling RTU over our North York clinic, fixed after hours so patients were not affected. Readings and photos came with the invoice." FAFarah A.Clinic manager, North York ## RTU offline or chiller alarm? Red Seal tech on the roof in 2-4 hrs across the GTA core. Call (437) TBD. (437) TBD [tel:+14370000000 →](tel:+14370000000) Emergency Service [/emergency-rooftop-unit-repair-toronto/ →](/emergency-rooftop-unit-repair-toronto/) Buyer questions ## RTU Repair FAQs Still have a question? A Red Seal lead answers, not a call centre. Written quote within 24 hours. Book a Site Assessment [/contact/ →](/contact/) (437) TBD [tel:+14370000000 →](tel:+14370000000) ### How much does commercial rooftop unit repair cost in Toronto? Most RTU repairs land between $275 and $5,600. A business-hours diagnostic runs $275-$425 and includes a written tally before work starts. Refrigerant leak search and recharge runs $850-$2,800 with R-410A at $85/lb. Economizer and controls diagnostics run $450-$900. A compressor repair or replacement runs $2,400-$5,600 depending on tonnage and access; our 7-ton Lennox LCG job on Dundas West came in at $3,850 all-in. Labour is $185/hr in business hours, $280/hr after-hours and $425/hr on weekends. HST is extra, and nothing is ordered until you approve the tally. ### How fast can you get a tech on my roof? Business-hours diagnostics are usually same day. For no-cool, no-heat or tripped-breaker emergencies, dispatch works inside a 30-minute window and a Red Seal tech is on the roof in 2-4 hours across the GTA core: Downtown Toronto, North York, Etobicoke, Scarborough, Mississauga, Markham and Vaughan. Restaurants, retail, dental and medical sites go to the front of the queue. Brampton and Oakville get same-day scheduled visits with emergency dispatch from the core. ### Should I repair or replace my rooftop unit? We look at age, repair history, refrigerant type and the size of the repair against the price of a new unit. A sound 8-year-old unit with a failed contactor is a repair every time. A 17-year-old R-22 unit that needs its second compressor usually is not worth it, especially once the Save on Energy rebate of $200-$1,500 per ton comes off a replacement. Our tally shows both numbers side by side so the decision is yours, made with real figures rather than a sales pitch. Typical commercial RTUs last 15-20 years on Toronto roofs with regular maintenance. ### What causes most rooftop unit failures in Toronto? Dirty coils, slipping belts, weak run capacitors and economizers that drift out of calibration cause most of the summer no-cool calls we see. In winter it is flame sensors, igniters, inducer motors and cracked heat exchangers in the gas section. Freeze-thaw cycles and road salt dust also corrode coil fins and electrical lugs on GTA roofs. Quarterly maintenance catches most of these before they shut the unit down. ### Do you repair every brand of commercial RTU? Yes. We are an authorized Lennox, Carrier, York, Trane, Daikin, Rheem and American Standard dealer and stock OEM parts for those lines. We also repair older Goodman, ICP and Keeprite commercial units when parts are still available, and we tell you plainly when they are not. ### Why does my RTU keep short cycling? Short cycling usually comes from an oversized unit, a low refrigerant charge, a failing high or low pressure switch, a bad thermostat location or a dirty evaporator coil. We check superheat and subcooling, read the controller fault history and test the safeties before replacing anything. Fixing the cause matters, because short cycling wears out compressors and contactors fast. ### What does the written tally include? The tally lists the failed parts, the labour hours, any crane or lift needs, the timeline and the total with HST shown on its own line. If the unit is old or the repair is large, it also includes a repair-vs-replacement note with the replacement range and any rebate that would apply. ### Can you fix an economizer that is stuck open or closed? Yes. Stuck economizers are one of the most misdiagnosed faults on commercial roofs. We test the actuator, damper linkage, enthalpy or dry-bulb sensor and the controller logic, then calibrate the changeover setpoint. An economizer stuck open in January can freeze coils and blow heating costs; stuck closed in shoulder season it wastes free cooling. ### Do you carry refrigerant for older units? We carry R-410A and the common low-GWP replacements on the van. R-22 is no longer manufactured, so recharging an R-22 unit relies on reclaimed refrigerant at a much higher cost. When an R-22 unit has a major leak we will usually recommend a replacement plan instead of pouring expensive refrigerant into a leaking system. ### Are your techs licensed for the gas section of my RTU? Yes. Our leads hold Red Seal 313A HVAC-R, TSSA G1 and G2 gas technician and ESA electrical certification, and our chiller techs hold CRE tickets. That means one crew can legally service the refrigeration, gas heat and electrical sections of a packaged unit without bringing in a second trade. ### Do you work after hours so tenants are not disrupted? Yes. Clinics, restaurants and offices often prefer evening or early-morning visits. After-hours labour is $280/hr and weekend labour is $425/hr, and both rates are shown on the tally before you approve the work. ### Do you provide a COI and service report for property managers? Yes. We issue a certificate of insurance within 24 hours on every PM request, carry $5M commercial liability and WSIB clearance, and leave a written service report with readings, photos and recommendations after every repair. Net-30 terms are available for commercial and PM accounts. Keep the whole roof covered ## Related Services ![Commercial rooftop unit with an open panel under work lights at dusk in Toronto](/images/misc/service-van-headlights-and-a-commercial-rooftop-un.webp) From $425 [/emergency-rooftop-unit-repair-toronto/ →](/emergency-rooftop-unit-repair-toronto/) ### Emergency Rooftop Unit Repair [/emergency-rooftop-unit-repair-toronto/ →](/emergency-rooftop-unit-repair-toronto/) No-cool, no-heat and tripped-breaker calls answered by a Red Seal tech, not a call-centre ticket. Details + pricing [/emergency-rooftop-unit-repair-toronto/ →](/emergency-rooftop-unit-repair-toronto/) ![Old rooftop unit lifted off a Toronto retail roof by crane during a replacement](/images/misc/old-rusted-rooftop-unit-being-lifted-off-a-toronto.webp) From $9,500 [/commercial-rooftop-unit-replacement-toronto/ →](/commercial-rooftop-unit-replacement-toronto/) ### Commercial Rooftop Unit Replacement [/commercial-rooftop-unit-replacement-toronto/ →](/commercial-rooftop-unit-replacement-toronto/) End-of-life RTU swaps with curb adapters, crane permits and rebate-net pricing. Details + pricing [/commercial-rooftop-unit-replacement-toronto/ →](/commercial-rooftop-unit-replacement-toronto/) ![Open commercial rooftop unit with clean coil and new filters during quarterly maintenance](/images/misc/clean-condenser-coil-and-fresh-merv-13-filters-in-.webp) From $240 [/commercial-rooftop-unit-maintenance-toronto/ →](/commercial-rooftop-unit-maintenance-toronto/) ### Commercial Rooftop Unit Maintenance [/commercial-rooftop-unit-maintenance-toronto/ →](/commercial-rooftop-unit-maintenance-toronto/) Quarterly RTU inspections with written reports, locked per-unit pricing and priority dispatch. Details + pricing [/commercial-rooftop-unit-maintenance-toronto/ →](/commercial-rooftop-unit-maintenance-toronto/) ## Don't See Your GTA City? Coverage from Toronto to Pearson, Mississauga to Markham. Call (437) TBD [tel:+14370000000 →](tel:+14370000000) for a 24-hour written quote. All Service Areas [/service-areas/ →](/service-areas/) Get a Written Quote [/contact/ →](/contact/) ![Packaged rooftop units on a Toronto commercial roof at dusk](/images/misc/toronto-commercial-rooftop-at-dusk-with-a-row-of-p.webp) 24/7 dispatch | 2-4 hr on-roof GTA core ## Ready to Book RTU Repair? Site assessment, then a written quote within 24 hours. Parts, labour, crane, permit and HST on one line. Book a Site Assessment [/contact/ →](/contact/) Call (437) TBD [tel:+14370000000 →](tel:+14370000000) - 24-hour written quote - Save on Energy filed for you - Red Seal + TSSA + ESA + CRE - $5M liability + WSIB