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Boiler Unit Installation in Markham, ON


Boiler Installation Toronto

Give DeMarco Mechanical Services Inc. a call for all residential and commercial boiler service and emergencies. We are a team of fully licensed HVAC contractors that have comprehensive knowledge of boiler, radiator and other electrical/mechanical problems. We offer a quick dispatch within 2 hours of your call and provide exceedingly quick repairs of both commercial and residential machines.

With our repair, replacement, inspection, and maintenance services, you can quickly solve any issues with your heating. You do not want to be left in the cold of Canadian winter, which is why we offer regular maintenance and safety inspections for commercial building and homes. In addition, we offer replacements for old boilers and radiators with new, energy efficient models that will save you money. We are your top rated choice for boiler service in Toronto, click here to read our HomeStars reviews!

Boiler installation in progress in Markham, ON

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Boiler Repair Toronto

Boiler Repair Toronto

We can help when your boiler breaks down. Your heating system is complex and delicate. At DeMarco Mechanical Services Inc. our staff are trained in a wide range of boiler repair and boiler replacement services in order to best serve you. These include:

  • Part Replacement: If your machine is old and failing or it has been damaged and needs to be fixed, we offer part replacement as part of our Toronto boiler repair services. We carry a wide range of branded parts to be able to perfectly service your device, and our work and parts come with a 100% customer satisfaction guarantee and a 30-day warranty.
  • Boiler Inspections and Cleaning: We clean and inspect heat exchangers, burners, and exterior cabinets, check operating pressures and temperatures, test and measure gas pressure and draft, test relief valves, check for gas leaks and carbon monoxide, and inspect venting, autofeeds, backflow preventers, expansion tanks and low water cut off.
  • Complete Boiler Replacement: Our machines do not last forever, and when they break down sometimes they are too-far-gone for repairs. Our technicians can perform boiler replacements in Toronto for you, and replace your existing machine with a newer one. The best part is that modern models tend to be more energy-efficient and effective anyway, meaning that you will be saving money in the long run by upgrading.

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Boiler Replacement Toronto

DeMarco Mechanical Services Inc. stocks a variety of boilers and water heaters from brands such as Bradford White, Rheem, Giant, Rinnai, Viessman, Navien, Weil McClain, NY Thermal and more. We offer boiler installation services of these new, energy-efficient products alongside popular models to further enhance the energy efficiency of your home or commercial building:

  • Combi Boilers: We offer space-saving, energy efficient combi boilers that can heat both your home and water supply. Boiler installation options include wall mounted units, which will free up space that a floored unit would otherwise take up. In addition, our new boilers are energy efficient and our clients see an increase in efficiency of up to 50%.
  • Condensing Boilers: Condensing boilers recover heat which would otherwise be lost as gasses. These wasted gasses travel through a heat exchanger, and the captured heat is used to pre-warm the cool water returning from your radiators. This makes the boiler more efficient and saves you energy.
  • Modulating Boilers: A modulating boiler has five separate setting, making them different from other models which only have an on/off setting. A modulating boiler can detect the heat of incoming water and adjust its settings to reduce fuel use when heating this water.

Residential and Commercial Boiler Repair Toronto


We are your local boiler service experts. DeMarco Mechanical Services Inc. provides residential and commercial repairs, general maintenance, inspections, replacement of parts, and full replacements of boilers and heating systems. With our help, you will find the best boiler to match the requirements of your home and family’s water consumption.

We are invested in customer service and satisfaction, which is why we offer the highest standard of service with every visit. With the help of our highly skilled technicians, your boiler repairs and replacements will be done in no time at all. Our technicians take the time to approach every problem with the same care and attention that they would show in their own homes.

Our company believes in creating a good relationship with our customers, which is why we offer multi equipment discounts, highly competitive rates, and service contracts throughout the entire GTA.

We are your top HVAC contractors, contact us today for your free consultation!

Boiler Services FAQ’s

What should the pressure be on a boiler?

The pressure on most boilers should be between 10-25 PSI with the recommended level at 10-20 PSI to prevent locking out. When the boiler is heating internal pressure should never exceed 28 PSI. Dropping pressure can be a sign of a leak, and if your pressure is too high you can adjust the feed water regulator to lower it.

Will frozen pipes thaw themselves?

Frozen pipes will thaw themselves if the temperature increases. For indoor pipes, you can open the cabinet doors and turn up the heat in your house to speed up the process. Beware: do not turn on the water if your pipes are frozen or they may burst, and thawing pipes can also cause leaks.

Why is my boiler making a whistling noise?

Your boiler may be making a whistling noise for one of three common reasons. This can be caused by kettling (limescale accumulating on the heat exchanger). Next, this can also be caused by trapped air in the boiler. Finally, there may be a loss of water pressure or a blockage in the boiler.

My boiler keeps cutting out. Why?

If your boiler keeps cutting out and restarting you may have one of the following problems: low water pressure (below 1 bar), fuel or water intake issues, a malfunctioning pump or thermostat, or air within the system. Contact a technician if you are unable to detect the problem for professional assistance.

Boiler not firing up for central heating. Why?

If your boiler is not firing up for central heating it may be because: the fan or electrodes are not functioning, the pilot light has gone out, there is insufficient gas or pressure, you have a blocked burner, or your gas valve is malfunctioning. These are the most common answers, a technician will be able to find your unique problem.