How Boilers Work

Conventional Boiler

Conventional Boilers uses gas or oil to heat up the water. Water is stored in a large tank and it’s heated on a continuous basis. The water is passed through the pipes and through the radiators to heat up the room. Conventional boilers have an efficiency rating of 70-80%.


Combi Boiler or Condensing Boiler

A combi boiler/condensing boiler, has a thermal efficiency rating up to 98%. Unlike a conventional boiler, which only heats the water, a condensing boiler, captures the water vapours in the flue gases and reuses it to give you additional heating energy. This process is referred to as the latent heat of vaporization.


In a Conventional Boiler, the unused heat is usually exhausted through the chimney. This heat source is wasted. A combi boiler/condensing boiler captures all the heat from the water plus the gases escaping from the chimney. It captures and utilizes it all, to give you additional heat.


Expansion Tank for Combi/Condensing Boiler

The combi boiler/condensing boiler doesn’t use a traditional water tank. The system is based on an on-demand service model, where water is only heated when it’s required, such as when you turn on the hot water tap. 


A condensing boiler/combi boiler is considered a closed-sealed system. The closed system doesn’t allow for the extra pressure to be pushed back to the city’s water system. Because of this, most municipalities will require an expansion tank to be installed with a combi heating system.


Benefits of an Expansion Tank  

Expansion tanks reduces unnecessary water wastage. In a closed-sealed system, extra pressure will have nowhere to go, except for the fixtures such as your water taps and toilets. The additional pressure may cause your faucets to drip and your toilets to run. With an expansion tank, it gives the water a place to expand, so extra pressure isn't built up in your water pipes. 

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77 Davisville Avenue, Unit 1104
Toronto, ON . M4S 1G3

Ph: 416-627-7724


261 Millway Ave., Unit 12
Concord, ON . L4k 4k9

Ph: 416-627-7724


1381 Trotwood Ave
Mississauga ON L5G 3Z7

Ph: 416-627-7724


23 Harold St Unit 12
Brampton ON L6Y 1C9

Ph: 905-450-0006


Greater Toronto Area (throughout the Toronto area), Mississauga, Brampton and Vaughan

To see the exact areas we service please refer to the Boiler Service Areas.

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