Boilers & Combi-Boilers: A Homeowner’s Guide
Choosing a boiler for your home heating, infloor radiant heat and hot water can feel overwhelming. Here’s a plain-English guide to traditional boilers vs. combi boilers, sizing, top brands and maintenance.
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Traditional Boilers vs. Combi Boilers
Boilers have heated homes for well over a century. Today the big choice is between a traditional boiler (paired with a separate hot water tank) and a combi boiler, which handles both space heating and on-demand hot water in one compact unit.
| Feature | Traditional boiler | Combi boiler |
|---|---|---|
| Space | Boiler plus a separate hot water tank | Compact, no tank needed |
| Efficiency | High, with some standby loss from the tank | Generally higher, heats water on demand |
| Hot water | Handles several taps at once well | Flow can drop with several taps running |
| Upfront cost | Usually higher (more parts) | Usually lower |
| Best fit | Larger homes, high hot-water demand | Small to medium homes |
Sizing Your Boiler
Proper sizing matters, especially in Southern Alberta winters. It depends on your home’s size, insulation, windows and airtightness, plus how much hot water you use.
As a rough guide, combi boilers are often matched to bathroom count:
| Input | Typical fit | Hot water flow |
|---|---|---|
| ~150,000 BTU | 2 bathrooms | ~6 GPM |
| ~160,000 BTU | 2.5 bathrooms | ~6.4 GPM |
| ~180,000 BTU | 3 bathrooms | ~7.2 GPM |
| ~199,000 BTU | 4+ bathrooms | ~7.9 GPM |
Top Brands to Consider
- IBC (Canada): Built in Burnaby, B.C., with modular designs and advanced controls. A favourite of ours.
- NTI (Canada): Compact, ENERGY STAR-certified boilers with built-in primary/secondary piping and clear diagnostic screens.
- Navien: A major North American player known for condensing technology and compact combi units.
- Rinnai: Reliable Japanese engineering, with app-monitoring options on many models.
- Viessmann: German-built, with stainless steel heat exchangers and some of the highest efficiencies available.
- Bosch: Compact, well-built condensing units with smart modulation.
Most modern condensing boilers from these brands are rated around 95% AFUE, with some premium models higher.
Essential Maintenance Tips
- Annual service: Combustion check, burner inspection and safety controls test.
- Vents and flues: Keep intake and exhaust clear of snow, ice and nests.
- Flush the system: Every few years, to remove sediment that hurts efficiency.
- Condensate: Keep the trap and drain clear on condensing models.
Need a boiler installed or serviced?
We install, service and repair traditional and combi boilers across Calgary and area, from wiring and controls to zoning and commissioning.
Boiler Repair Calgary FAQ
Do you offer emergency boiler repair in Calgary, Springbank and Bragg Creek?
Yes. Call or text 403-619-2856 any time, day or night, for emergency boiler repair across Calgary, Springbank and Bragg Creek. If your boiler has locked out, don't keep resetting it; note any error code on the display and call us.
What are the signs my boiler needs repair?
Cold zones or radiators, banging or kettling noises, system pressure that keeps dropping, water around the boiler or pipes, or an error code on the display are all signs it needs attention. Catching these early usually means a smaller repair.
What is the difference between a boiler and a combi-boiler?
A standard boiler heats water for your heating system and is often paired with an indirect tank for domestic hot water. A combi-boiler does both in one wall-mounted unit, heating your home and supplying hot water to your taps on demand.
Can you replace a circulator pump or zone valve?
Yes. Circulator pumps, zone valves and actuators are some of the most common hydronic failures. We diagnose the whole system, replace the failed part and check the wiring and controls so the problem doesn't come back.
Do you repair electric hot water tanks in Calgary?
Yes. We troubleshoot and replace heating elements, thermostats and wiring on electric hot water tanks, and replace the tank when it's reached the end of its life.
How often should a boiler be serviced?
Once a year, ideally before heating season. A service checks combustion, pressure, pumps, valves and controls, and helps prevent mid-winter breakdowns.
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