What Is a Combi Boiler and How Does It Work? | ROMA Heating Vancouver
A combi boiler (combination boiler) is a single unit that provides both home heating AND instant domestic hot water — eliminating the need for a separate hot water tank. Combi boilers are the most popular new boiler installation choice in Greater Vancouver, especially for condos and smaller homes. ROMA Heating & Cooling has been Greater Vancouver’s trusted HVAC contractor since 1999. We’re TSBC-licensed, fully insured, and rated 4.8★ by over 158 verified customers.
How a Combi Boiler Works
A combi boiler has two separate modes:
- Space heating mode — hot water circulates through your home’s radiators, baseboard heaters, or in-floor radiant tubing when the thermostat calls for heat
- Domestic hot water mode — when a hot water tap is opened, the boiler diverts to heating cold incoming water on demand — no storage tank needed
The transition between modes is automatic and instantaneous. Modern combi boilers can handle both simultaneously in some models, or priority-switch between them.
Benefits of a Combi Boiler for Greater Vancouver Homes
- No hot water tank — frees up significant space in your utility room or closet
- Endless hot water — no tank to run out of; hot water on demand for as long as needed
- Higher efficiency — no standby heat loss from a hot water tank sitting idle
- One appliance, one annual service — simplifies maintenance
- Lower installation cost — one unit replaces two (boiler + water heater)
- Compact footprint — ideal for Vancouver condos, townhouses, and smaller homes
Best Combi Boilers for Greater Vancouver
- Navien NCB series — most popular in BC; 97% AFUE; built-in buffer tank for hot water volume; outstanding reliability
- IBC SH series — Canadian-made; excellent cold-weather performance
- Rinnai i-Series — strong hot water performance; compact design
- Viessmann Vitodens 222-W — premium German engineering; integrated hot water storage
Is a Combi Boiler Right for Your Home?
Combi boilers work best for: homes under 2,500 sq ft, 1–2 bathrooms, up to 2 simultaneous hot water users. For larger homes with 3+ bathrooms or high simultaneous hot water demand, a separate boiler + storage water heater may be more appropriate.
Service Areas
ROMA installs combi boilers throughout Vancouver, Burnaby, Richmond, Surrey, Coquitlam, New Westminster, North Vancouver, West Vancouver, Port Moody, Port Coquitlam, Delta, Langley, Maple Ridge, Pitt Meadows, and Abbotsford.
- Can a combi boiler supply enough hot water for a family in Vancouver?
- Most combi boilers provide 3.5–5.5 gallons per minute (GPM) of hot water — enough for one shower or dishwasher at a time. The Navien NCB series with its built-in buffer tank handles simultaneous demand better than older combis. For families with two bathrooms running simultaneously, a slightly larger combi or a separate storage system may be preferable.
- How much does a combi boiler installation cost in Vancouver?
- Combi boiler installation in Vancouver typically costs $5,000–$8,500 installed — more than a heating-only boiler but less than a separate boiler + water heater. The savings from eliminating the hot water tank plus FortisBC rebates of up to $1,000 offset the cost difference.
- What happens to my hot water when the combi boiler is being serviced?
- During an annual service visit (typically 1.5–2 hours), the boiler is shut down temporarily — meaning no heating or hot water during that window. ROMA schedules maintenance during milder weather and moves efficiently to minimize downtime.
- Can I install a combi boiler to replace just my old water heater?
- Yes — if you have an existing conventional boiler for heat and want to eliminate a failing water heater, switching to a combi replaces both appliances in one. This typically costs $5,500–$8,000 including removal of the old water heater.
- Do combi boilers work with in-floor radiant heating?
- Yes — combi boilers are compatible with in-floor radiant heating, though a mixing valve is typically required to reduce the water temperature to safe floor levels (40–55°C). ROMA designs and installs complete combi + radiant systems throughout Greater Vancouver.
Related Services
- furnace repair Greater Vancouver
- boiler repair Greater Vancouver
- heat pump installation Greater Vancouver
Book Your Service
Call ROMA Heating & Cooling at (604) 924-7273 or request a free quote online. Serving Greater Vancouver since 1999 — TSBC licensed, fully insured.
What Greater Vancouver Homeowners Say
“Nelson worked hard to get the NTI unit fixed. He was always polite, courteous and on time.”
“As always Nelson was super efficient. Showed up on time and was quick to work. I had a full maintenance done on the fireplaces and furnace. He was awesome. I won’t use anyone else.”
“Excellent service. Andy had a spare Carrier inducer with him which saved us time.”
“Was very prompt to respond to our issues. Technician was scheduled for the day following my initial call.”
“Very professional heating company. Price is reasonable, excellent work.”
“Highly recommend this company. It was a pleasure dealing with Shawn and Nelson.”
“Professional and courteous technicians with attention to detail and customer needs.”
“Always great, friendly service. Serviced the hot water on-demand system. Honest and informative. Thanks!”
“Speedy response time, honest, and professional service from start to finish.”
Why Greater Vancouver Trusts ROMA Heating & Cooling
ROMA Heating & Cooling has installed, repaired and maintained heating and cooling systems across Metro Vancouver since 1999. Our team are TSBC-licensed gas fitters (Gas LGA0202903) and Red Seal-trained technicians — licensed, bonded and insured — and we back every job with upfront, flat-rate pricing and a 100% satisfaction guarantee. We hold a 4.8★ rating from 221+ Google reviews.
- Authorized for 30+ brands (Lennox, Carrier, Viessmann, Navien, Rheem & more)
- Upfront flat-rate pricing — no overtime or hidden fees
- Free, no-obligation estimates on new installations
- Locally owned & operated in Burnaby, BC
No Hidden Fees
Our service rates are transparent and easy to understand. You approve upfront, flat-rate pricing before we start — so you never get a bill you didn’t expect.
Licensed & Bonded
ROMA is a TSBC-licensed gas contractor (Gas LGA0202903). Our technicians are bonded, insured and Red Seal-trained — qualified for any heating or cooling system.
Free Estimates
We offer free, no-obligation estimates on new installations — furnaces, boilers, heat pumps, air conditioners, tankless and hot-water tanks.
ROMA Heating & Cooling is a trusted HVAC contractor serving Metro Vancouver since 1999. We specialize in furnace repair, heat pump installation, boiler services, air conditioning, and emergency heating solutions for residential, commercial, and government clients. Available 24/7, our certified technicians deliver fast, reliable, and affordable HVAC services across Greater Vancouver.