If you live in Toronto, North York, or Vaughan, chances are your home has hard water — and that means your tankless combi boiler may be working harder than it should. These high-efficiency systems are great for saving space and energy, but over time, limescale buildup inside the boiler can reduce performance, increase energy bills, and even lead to premature failure.
One of the most common questions we get from homeowners across the GTA is:
“How often should I descale my tankless combi boiler?”
In this guide, we’ll break down everything you need to know about descaling: why it matters, how often you should do it, and what signs to watch for — especially in areas like Toronto where water hardness is a real concern.
Why Descaling Matters
Descaling is the process of removing calcium and mineral deposits that build up inside your boiler’s heat exchanger. These deposits are especially common in hard water regions — like much of Toronto, Vaughan, and surrounding parts of southern Ontario.
When left untreated, scale buildup can cause:
Reduced water flow and pressure
Increased gas usage and energy bills
Overheating and system errors
Shortened boiler lifespan
Inconsistent hot water supply
For homeowners relying on a tankless system for both heating and hot water, regular maintenance is critical.
So, How Often Should You Descale?
Most experts — including boiler manufacturers — recommend descaling every 12 to 18 months. However, your situation may vary depending on:
1. Water Hardness
In areas like Vaughan and North York, water hardness can be moderate to high. If you’re in one of these zones, descaling once a year is highly recommended.
2. Boiler Usage
Larger households or properties using more hot water on a daily basis will experience faster buildup. If your boiler works hard year-round, annual descaling is a smart investment.
3. Manufacturer’s Warranty
Some warranties require regular descaling as part of the maintenance plan. Skipping this step may void your coverage, especially if you’re using brands like Navien, Bosch, or Rinnai.
Warning Signs It’s Time to Descale
Even if it hasn’t been a full year, your system may already show signs that it needs attention. Look out for:
Drop in hot water pressure
Boiler is taking longer to heat water
Error codes on your boiler screen
Strange noises (popping, hissing, or gurgling)
Higher-than-normal energy bills
If you’re experiencing any of these symptoms, call a licensed boiler technician in Toronto for a descaling service right away.
Can I Descale My Boiler Myself?
While there are DIY kits available, professional descaling is safer and more effective. Here’s why:
Professionals use the correct non-corrosive descaling solutions
They flush the entire system thoroughly
They can inspect your boiler for other potential issues
It’s faster, safer, and doesn’t risk your warranty
If you’re not comfortable working with plumbing and electronics — or just want peace of mind — it’s best to schedule an annual service with a trusted HVAC technician in North York or Vaughan.
What Are the Benefits of Regular Descaling?
Maintaining your tankless combi boiler pays off in many ways:
✅ Lower energy bills — Your unit runs more efficiently
✅ Consistent hot water — No pressure loss or inconsistent temperatures
✅ Extended equipment life — Prevent costly breakdowns
✅ Peace of mind — You’ll know your system is winter-ready
✅ Warranty protection — Keeps you compliant with manufacturer requirements
In a city like Toronto where the winters are harsh and reliable heating is a must, ensuring your boiler is scale-free is not just smart — it’s essential. Regular descaling will help your tankless combi boiler last longer, run better, and keep your home comfortable year-round.
If it’s been more than a year since your last boiler flush — or you’re starting to notice performance issues — now’s the time to act. Call your local HVAC experts for professional descaling services in Vaughan, North York, or Toronto.
