# Boiler Repair Toronto | Standard & Major Repair CAD

URL: https://boilerinstallationtoronto.ca/boiler-repair-toronto/

Toronto Boiler Installation

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# Boiler Repair in Toronto: Standard and Major Component Repair for Ignition, Pressure and Heat Exchanger Faults Across the GTA

Last updated: September 19, 2026

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.

Published band $200 - $3,500 CAD standard to major repair (CAD)

Call (647) 254-9788

[tel:+16472549788 →](tel:+16472549788)

 

View CAD Pricing

[#pricing →](#pricing)

-   TSSA G1/G2 Licensed
-   22 Years Experience
-   Same-Day GTA Dispatch
-   Written Workmanship Warranty

![Technician testing an ignition control board inside an opened Toronto boiler casing](/images/misc/technician-with-a-multimeter-testing-an-ignition-c.webp)

-   5-Star Customer Satisfaction
-   Same-Day GTA Emergency Dispatch
-   22 Years of Boiler Installation Experience
-   Written Workmanship Warranty

## What Is Boiler Repair in Toronto?

Boiler repair in Toronto splits into two published CAD bands. Standard component repairs run $200 to $1,200 CAD and cover circulator pumps, expansion tanks, sensors, aquastats, pressure relief valves, and ignition control boards. Major component repairs run $1,200 to $3,500 CAD and cover heat exchangers, cast iron sections, gas valves, and circuit boards. The diagnostic that establishes which band you are in is $99 to $249 CAD in business hours, $199 to $349 CAD after hours, and is waived when you authorise the work on the same visit.

Publishing those numbers matters because boiler repair is one of the few trades where the customer genuinely cannot tell whether the price is fair. A seized circulator and a cracked heat exchanger present identically to a homeowner: no heat. One is a $980 CAD afternoon and the other is a replacement conversation. Every diagnostic we run ends with a written repair-versus-replace comparison so the decision is made on numbers.

![Written repair-versus-replace comparison sheet on a clipboard resting on a Toronto boiler casing beside a flue gas analyser](/images/misc/written-repair-versus-replace-comparison-sheet-on--2.webp)

## How Much Does Boiler Repair Cost in Toronto?

| Repair | CAD band | Typical band |
| --- | --- | --- |
| Circulator pump replacement | $450 - $1,200 | Standard |
| Expansion tank replacement | $250 - $550 | Standard |
| Zone or mixing valve repair | $250 - $650 | Standard |
| Thermocouple or flame sensor | $200 - $450 | Standard |
| Ignition control board or module | $350 - $850 | Standard |
| Aquastat or boiler thermostat | $250 - $650 | Standard |
| Pressure relief valve replacement | $200 - $450 | Standard |
| Heat exchanger repair or replacement | $1,200 - $3,500 | Major |
| Cast iron sectional replacement | $1,500 - $3,500 | Major |
| Gas valve replacement | $650 - $1,400 | Major |
| Boiler circuit board replacement | $600 - $1,400 | Major |
| Radiator repair or replacement | $450 - $1,200 per unit | Major |

Every quote itemises the diagnostic fee, parts, labour, permits where required, and disposal. Nothing is fitted without your authorisation and nothing appears on the invoice that was not on the quote.

## The 5 Faults We Diagnose Most Often

**1\. Pressure that will not hold.** Usually a failed expansion tank pre-charge rather than a leak. With no air cushion behind the diaphragm, heated water has nowhere to expand, system pressure spikes, the relief valve opens, and water is lost every cycle. The homeowner sees a pressure gauge dropping and often replaces a perfectly healthy relief valve. Correct diagnosis is a pre-charge measurement, and the fix is $250 to $550 CAD for the tank.

**2\. Ignition lockout.** The boiler tries, fails, and locks out with a fault code. Most often a dirty flame ionisation rod giving a weak microamp signal, sometimes a worn or badly gapped spark electrode, occasionally a failing ignition module at $350 to $850 CAD. Cleaning and re-gapping resolves a surprising share of these within a service visit.

**3\. No circulation.** The boiler fires, the supply pipe gets hot, and nothing reaches the radiators. A seized circulator cartridge, an air lock, or a stuck zone valve actuator. Circulator replacement is $450 to $1,200 CAD, covered in detail on 

Boiler Pump Replacement Toronto

[/boiler-pump-replacement-toronto/ →](/boiler-pump-replacement-toronto/)

.

**4\. Heat exchanger failure.** Pressure loss with no visible leak, rust staining at the base of the unit, or condensation in a flue that should be dry. On a condensing unit this is $1,200 to $3,500 CAD. On a cast iron sectional it means section replacement at $1,500 to $3,500 CAD, and on a unit past 25 years it triggers the replacement conversation.

**5\. Control drift.** The boiler runs but the house is uncomfortable. An aquastat out of calibration, an outdoor reset curve set at the factory default, or zone valves desynchronised. Often the cheapest fix in the list and the one most frequently misdiagnosed as an equipment problem. See 

Boiler Controls and Thermostat Toronto

[/boiler-controls-and-thermostat-toronto/ →](/boiler-controls-and-thermostat-toronto/)

.

## What Actually Stops Toronto Homeowners From Calling

The main hesitation is not knowing whether a call will end in a $240 CAD fix or a $10,000 CAD replacement, and there is no way to know without a diagnostic. That is exactly why the diagnostic fee is waived when you authorise work on the same visit: the risk of finding out should not be a barrier.

The second hesitation is suspicion that a repair quote is really a sales route to a replacement. It is a fair concern in this trade. Our answer is procedural rather than promissory: you get the repair cost and the replacement cost side by side in writing, with the remaining service life estimate, the current measured combustion efficiency, and the rebate offset shown. Roughly one call in five ends with us quoting the repair on a unit we could easily have argued for replacing.

The third is licensing. Ontario requires TSSA G1 or G2 certification for gas boiler work, and manufacturer warranties require both licensed labour and genuine parts. The technician’s certificate number appears on your invoice. Ask any contractor for it.

## When Repair Stops Being the Right Answer

There is a point where repair spending is preserving a liability. The signals are cumulative rather than singular.

A unit past 25 years measuring 60 to 70 percent efficiency on a combustion analysis. A second major repair inside two years. A heat exchanger quote above $2,500 CAD on a cast iron sectional. Parts becoming difficult to source, which on pre-2005 equipment is increasingly common. Any two of those together and the maths generally favours a 

high-efficiency replacement

[/high-efficiency-boiler-installation-toronto/ →](/high-efficiency-boiler-installation-toronto/)

, particularly once up to $11,500 CAD in combined Enbridge and Canada Greener Homes rebates are applied against a 25 to 35 percent reduction in gas consumption.

We put both paths in writing and we do not push. The comparison is more persuasive than any argument we could make.

## How Our Toronto Boiler Repair Process Works

Symptom intake on the phone covering what the boiler is doing, how long it has done it, any fault code on the display, and the unit’s age and brand, so the right parts are on the truck. On-site diagnosis with combustion analysis, electrical testing, pressure history, and control verification to identify the actual fault rather than the loudest symptom. Written quote in CAD against the published bands before any part is fitted, with the repair-versus-replace comparison alongside. Repair on the same visit wherever the part is carried, which covers most standard component work. Test and verify with post-repair combustion analysis, a pressure check, and a full heating cycle observed before the technician leaves. Report and warranty issued listing the readings, the parts fitted, the TSSA certificate number, and the written workmanship warranty.

If the house has no heat right now, go to 

Emergency Boiler Repair Toronto

[/emergency-boiler-repair-toronto/ →](/emergency-boiler-repair-toronto/)

 for 24 hour dispatch and red-tag clearance. If the boiler is running but you want to prevent the next fault, 

Boiler Maintenance and Annual Service

[/boiler-maintenance-toronto/ →](/boiler-maintenance-toronto/)

 at $199 to $349 CAD is the better spend. For the full range of 

boiler installation and repair services in Toronto

[/ →](/)

, including published CAD bands on every scope, start at the overview.

Transparent CAD Pricing

## How Much Does Boiler Repair Cost in Toronto?

Published on the page, never gated. Every quote itemises parts, labour, TSSA permits, and disposal in Canadian dollars before any work starts.

### Diagnostic Service Call

$99 - $249 CAD

-   Full fault diagnosis with combustion analysis
-   System pressure and control verification
-   Written repair-versus-replace comparison
-   Waived when you authorise work on the same visit

Get This Quoted

[tel:+16472549788 →](tel:+16472549788)

Most Requested

### Standard Component Repair

$200 - $1,200 CAD

-   Circulator pump replacement $450 - $1,200 CAD
-   Expansion tank replacement $250 - $550 CAD
-   Ignition control board or module $350 - $850 CAD
-   Aquastat, flame sensor or PRV $200 - $650 CAD

Get This Quoted

[tel:+16472549788 →](tel:+16472549788)

### Major Component Repair

$1,200 - $3,500 CAD

-   Heat exchanger repair or replacement $1,200 - $3,500 CAD
-   Cast iron sectional replacement $1,500 - $3,500 CAD
-   Gas valve replacement $650 - $1,400 CAD
-   Circuit board replacement $600 - $1,400 CAD

Get This Quoted

[tel:+16472549788 →](tel:+16472549788)

Diagnostic is $99 to $249 CAD business hours and $199 to $349 CAD after hours, waived when you authorise the repair or installation on the same visit. Every diagnostic ends with a written repair-versus-replace comparison.

Why Choose Us

## Why Choose Us for Boiler Repair

### 22 Years of Boiler Installation Experience

Two decades diagnosing condensing, combi, cast iron, and radiant faults across Toronto and the GTA.

### Published Repair Bands

$200 to $1,200 CAD standard, $1,200 to $3,500 CAD major. Published on the page so you know the range before we arrive.

### Diagnostic Waived on Authorisation

Authorise the repair or installation on the same visit and the $99 to $249 CAD diagnostic comes off the invoice.

### Written Repair-Versus-Replace, Every Time

On older units you get the repair cost set against remaining life, gas savings, and rebate offset before you decide.

### Common Parts Carried on the Truck

Circulators, expansion tanks, sensors, and ignition boards for the common GTA units. Most standard repairs close on the first visit.

### TSSA G1/G2 Licensed Technicians Only

Every repair meets Ontario B149 fuel code, with the certificate number printed on your invoice.

The Framework

## How Our Boiler Repair Process Works

1.  1
    
    ### Symptom intake
    
    What the boiler is doing, how long it has been doing it, any fault code on the display, and the unit's age and brand.
    
2.  2
    
    ### On-site diagnosis
    
    Combustion analysis, electrical testing, pressure history, and control verification to identify the actual fault rather than the loudest symptom.
    
3.  3
    
    ### Written quote in CAD
    
    The repair priced against the published bands before any part is fitted, with the repair-versus-replace comparison alongside it.
    
4.  4
    
    ### Repair on the same visit where possible
    
    Common circulators, expansion tanks, sensors, and ignition boards are carried on the truck. Most standard repairs close first visit.
    
5.  5
    
    ### Test and verify
    
    Post-repair combustion analysis, pressure check, and a full heating cycle observed before the technician leaves.
    
6.  6
    
    ### Report and warranty
    
    Written report with readings, the parts fitted, the technician's TSSA certificate number, and the workmanship warranty.
    

## Want a written CAD quote for boiler repair?

Published pricing bands, TSSA-licensed technicians, and the diagnostic waived on same-visit authorisation.

(647) 254-9788

[tel:+16472549788 →](tel:+16472549788)

 

Get CAD Quote

[/contact/ →](/contact/)

Our Work

## Boiler Repair Work Across Toronto and the GTA

Click any image to enlarge.

 

Customer Feedback

## What Customers Say About Our Boiler Repair Work

> Intermittent lockout that three other people had guessed at. They tested the flame rod signal, found it weak, cleaned and re-gapped it, and it has not faulted since. $240 CAD.

Trevor W.

Wexford

5-Star Customer Satisfaction

> Circulator had seized. Replaced with an ECM pump from the truck on the first visit and the system purged properly afterward. $980 CAD, diagnostic waived.

Sunita J.

Bramalea

Top-Rated Contractor

> Gas valve failure on a fourteen year old unit. They showed us the repair against the replacement numbers in writing and we chose the repair. $1,150 CAD.

Edgar M.

Don Mills

Trusted by Homeowners and Businesses

Got Questions?

## Boiler Repair FAQs

### How much does boiler repair cost in Toronto?

Standard component repairs run $200 to $1,200 CAD and major component repairs run $1,200 to $3,500 CAD. Within the standard band, a circulator pump replacement is $450 to $1,200 CAD, an expansion tank $250 to $550 CAD, a zone or mixing valve $250 to $650 CAD, a thermocouple or flame sensor $200 to $450 CAD, an ignition control board $350 to $850 CAD, an aquastat $250 to $650 CAD, and a pressure relief valve $200 to $450 CAD. The diagnostic is $99 to $249 CAD in business hours and is waived when you authorise the repair on the same visit.

### What is the diagnostic fee and when is it waived?

The diagnostic is $99 to $249 CAD during business hours and $199 to $349 CAD after hours. It covers a full fault diagnosis with combustion analysis, electrical testing, pressure verification, control checks, and the written repair-versus-replace comparison. It is waived entirely when you authorise the repair or an installation on the same visit, so in practice most customers do not pay it separately.

### My boiler keeps losing pressure. What causes that?

Three common causes in order of likelihood. First, a failed expansion tank pre-charge: with no air cushion, the expanding water forces the pressure relief valve open and the system loses water every heating cycle. Second, a weeping pressure relief valve, often the downstream result of the first problem. Third, a genuine leak, either in the loop, at a radiator valve, or inside the boiler itself. A cracked section shows as pressure loss with no visible leak anywhere in the house. The diagnostic distinguishes between them rather than replacing parts in sequence.

### The boiler is locking out on ignition. Is that expensive?

Usually not. Ignition lockout is most often a dirty flame ionisation rod giving a weak microamp signal, a worn or incorrectly gapped spark electrode, or a failing ignition control module. The first two are cleaning and adjustment within the service visit. A control board is $350 to $850 CAD. It becomes expensive only when the gas valve itself has failed, at $650 to $1,400 CAD, and that is confirmed by testing rather than assumed.

### When is a repair not worth doing?

When the repair cost approaches a meaningful fraction of replacement on a unit already past its efficient life. A $2,800 CAD heat exchanger on a 27 year old cast iron sectional running at 65 percent efficiency is money spent to preserve high fuel bills. Against that, a $10,300 CAD condensing retrofit with up to $11,500 CAD in combined Enbridge and federal rebates and a 25 to 35 percent gas reduction is the better allocation. The written repair-versus-replace comparison puts both numbers side by side. See Boiler Replacement Toronto.

### What is a written repair-versus-replace analysis?

A one-page comparison handed over at the end of every diagnostic. One side shows the repair cost in CAD and the realistic remaining service life given the unit's age, its measured combustion readings, and the condition of the heat exchanger. The other shows the installed replacement cost, projected annual gas savings from a 95%+ AFUE unit, and the rebate offset. It exists so the decision rests on numbers rather than on whoever is standing in your basement sounding confident.

### Do you carry parts on the truck?

Yes, for the units common across the GTA. Circulators, expansion tanks, flame sensors, thermocouples, pressure relief valves, and ignition boards for Navien, Viessmann, Weil-McLain, Bosch, Rinnai, NTI, IBC, Lochinvar, and Buderus. Most standard component repairs close on the first visit. Major components such as heat exchangers and cast iron sections are ordered against the specific unit, which typically adds one to three business days.

### Will a repair void my manufacturer warranty?

Not when it is done correctly. Manufacturer warranties require the work to be performed by a licensed technician using genuine parts. We hold TSSA G1 and G2 certification and source parts from Ontario distributors, which are the two conditions manufacturers check. Using generic parts or unlicensed labour is what voids coverage, which is why the cheapest quote is sometimes the most expensive outcome.

### Why does one room stay cold when the boiler is working fine?

That is a distribution fault, not a boiler fault. The usual causes are trapped air in a radiator or loop, an unbalanced circuit where the nearest emitters take all the flow, a stuck zone valve actuator, or a circulator that has lost head on one loop. Replacing the boiler will not change any of them. See Hydronic Heating and Radiator Installation Toronto for the balancing and air elimination work that does.

### How quickly can you get here?

Same-day dispatch across all ten GTA cities we cover, and four-hour response on no-heat calls during a cold snap. If the house is cold right now, Emergency Boiler Repair Toronto covers the 24 hour service including red-tag clearance and frozen condensate.

### Do you repair boilers you did not install?

Yes, and most of our repair work is on systems installed by others. Manufacturer certification across the major brands means we can source genuine parts and keep your existing warranty intact. A first visit on an unfamiliar system takes slightly longer because we establish baseline readings, which then serve as the reference for any future work.

### What warranty covers the repair itself?

A written workmanship warranty on our labour plus the manufacturer warranty on any part supplied. The service report lists the parts fitted, the combustion readings taken before and after, and the TSSA certificate number of the technician who performed the work.

### 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/)

## Related Services

![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)

### 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.

View service

[Emergency Boiler Repair Toronto →](/emergency-boiler-repair-toronto/)

![New variable-speed ECM circulator fitted to the return line of a Toronto boiler with isolation flanges](/images/misc/new-variable-speed-ecm-circulator-pump-fitted-to-t.webp)

### Boiler Pump Replacement Toronto

Circulator and ECM pump replacement for noisy, seized, or leaking boiler pumps, published at $450 to $1,200 CAD including labour, with the system purged and rebalanced after the swap.

View service

[Boiler Pump Replacement Toronto →](/boiler-pump-replacement-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)

### 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.

View service

[Boiler Maintenance and Annual Service Toronto →](/boiler-maintenance-toronto/)

![](/images/misc/tssa-licensed-technician-closing-the-front-panel-o.webp)

Same-Day Emergency Dispatch, 24/7 Cold Snap Response

## Ready to Book Boiler Repair in Toronto?

Every boiler repair quote itemises parts, labour, TSSA permits, and disposal in Canadian dollars 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