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Combi Boiler Calgary: Three Facts of Life

ibc boilers

As Calgary’s Combi Boiler experts we would like to share some insights into this technology.

Hydronic heating is nothing new. In fact, it’s been around since the mid-1800s; only the technological details have changed. Where once you would have had a massive central boiler that served an entire building, or perhaps a connection to a municipal district heating service, nowadays we see small self-contained systems.

The advantages of this are greater control, efficiency, and redundancy, in that the failure of one boiler won’t take heat from the entire building.

Accordingly, combi boilers are becoming more and more commonplace, especially in apartment condominium complexes. They’re called combi boilers because they employ a single heat exchanger in a double-duty combination, heating both the domestic hot water supply and the fluid circulated through floors, ceilings or radiators in a hydronic heating system.

Consider the oil in your car: if you never change the oil, the car will continue to run for quite some time, but you’ll create a condition inside the engine that will drastically shorten its operational life, leading to premature and expensive repairs.

If you’ve acquired a property that employs one or more of these boilers, you owe it to yourself to know the three things they require to operate safely and to avoid costly failures: proper ventilation, good water quality, and annual visits for monitoring and inspection.

What is a Combi Boiler?

A combination boiler, commonly known as a combi boiler, is a highly efficient and compact heating system that provides both space heating and domestic hot water on demand.

Unlike traditional boilers, which require a separate water heater and a storage tank, a combi boiler combines these functions into a single unit. This integration not only saves space but also improves efficiency and reduces installation costs.

Key Features of Combi Boilers:

  1. Space-Saving Design: Combi boilers are ideal for smaller homes or apartments where space is at a premium. Their compact size allows them to be installed in kitchens, utility rooms, or even airing cupboards without taking up much room.
  2. On-Demand Hot Water: One of the primary benefits of a combi boiler is its ability to provide instant hot water. There’s no need to wait for a storage tank to heat up, making it convenient for households with high hot water demand.
  3. Energy Efficiency: Combi boilers are designed to be highly energy-efficient, which can lead to significant savings on energy bills. They use modern condensing technology to maximize heat extraction from fuel, resulting in lower carbon emissions.
  4. Simplified Installation: Since there is no need for a separate hot water cylinder or cold water storage tank, the installation process of a combi boiler is simpler and generally quicker. This can also reduce the overall installation costs.
  5. Consistent Water Pressure: Combi boilers deliver hot water at mains pressure, ensuring powerful showers and quick filling of baths. This eliminates the need for additional pumps or pressure boosters.

How Does a Combi Boiler Work?

A combi boiler operates by heating water directly from the mains supply as soon as a hot water tap is turned on. When the central heating is needed, the boiler’s heat exchanger warms the water circulating through the radiators. The dual function is managed seamlessly by the boiler’s internal controls, ensuring that the system provides heat and hot water efficiently.

Proper Combustion Airflow

As with all things that burn gas, venting is literally a matter of life and death! Every gas appliance needs to breathe properly. Not only is it vital to have expert installation and strict adherence to building codes, but over time incidental damage or obstruction can interfere with intake and exhaust vents. The best way to determine this is visual inspection coupled with combustion testing.

Just one example of do-it-yourself-ism gone wrong: many such boilers have dual venting schemes (one for concentric venting, and one for separate intake and exhaust). Any time a gas appliance is not getting adequate intake air, it should shut itself down; this is a good thing! However, if one were to remove the plug on the alternate intake, the appliance might resume. This is not a safe operating condition, as it merely defeats a vital safety feature and runs the risk of elevating carbon monoxide levels in your home.

Water Quality of Combi Boilers

With the combi boiler, water quality is a twofold concern. We’re not just talking about the domestic supply, but also the water/glycol mix used for heating the home.

For domestic supply, soft water is a requirement. As we’ve mentioned previously, Calgary’s water supply is exceptionally clean, safe, and high in mineral content. The hardness of the water here makes the inclusion of a water softener a necessity with your combi boiler.

You’ll find this stated in your equipment manual, but sadly too many condominium developers have ignored this. If your boiler fails in the first five years due to an excessively hard domestic water supply, you’ll find it’s not covered by the warranty. This is potentially a ten thousand dollar trap for second-hand condominium owners, so buyer beware!

For the hydronic heating, a chemically stable, oxygen depleted mixture with correct pH balance is essential for the prevention of mineral buildup and to prevent corrosion of internal parts.

Sure, the heating system could successfully operate with simple tap water, but that would also contain unacceptable levels of chlorine, about 8% dissolved air (including oxygen to corrode internal parts) not to mention mineral content.

Over time, as the fluid recirculates, this would lead to the system becoming fouled with calcium deposits and the byproducts of it own internal corrosion. It’s not a pretty picture, and it’s not cheap to fix. This is why we use an inhibited glycol mixture to keep all these factors under control, and this mixture requires regular monitoring.

Combi Boiler Maintenace

All too often owners of these systems regard them as a simple widget that’s either heating water or not; as long as they have hot water, everything must be OK, right? This “what, me worry?” approach will cost you big time. Just running it until it won’t run anymore is a sure fire method to shorten the life of your expensive equipment.

Like maintaining your car, regular inspection and scheduled maintenance can make the difference between your combi boiler lasting five years versus fifteen to twenty. In the life of a boiler, component failures will occur, but vigilance in the form of annual service means affordable fixes will be far more likely than expensive disasters!

Call for a Free Consultation

We have extensive experience installing and maintaining combi boilers. Common brands include Baxi, Navien, Rinnai, Laars and IBC, but they all require the same tender loving care! Call and talk to one of our hydronic heating experts if you have questions about your combi boiler.

George Pinel
George Pinel

Master Plumber

I have been involved in this family owned business for 33 years now.

It has always been and will continue to be the core focus of Instant Plumbing & Heating to provide a long lasting relationship with our customers based on trust and integrity of our service and products.

This achieved by using the best quality materials. I as a business owner continue to mentor and treat my staff with the highest regard and respect, this interns helps them deliver to the client great quality workmanship and service.

It is our professional goal to leave a situation better than when we arrived both in how we do our work and in how you feel for having chosen us to do your work, we are in the anxiety reduction business using plumbing and heating service work to do it.

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