Why Furnace Size Matters: How to Choose the Right Fit for Your Ottawa HomeBy Clockwork HVAC | Ottawa Heating Experts
When it comes to staying warm during an Ottawa winter, having a reliable furnace is non-negotiable. But if you think a bigger furnace automatically means better heating—think again.
At Clockwork HVAC, we regularly help homeowners who are dealing with underperforming or oversized furnaces that waste energy, create uneven temperatures, and lead to higher bills. The truth is, furnace size matters, and getting it wrong can cost you in more ways than one.
Let’s break down why furnace sizing is so important, and how to make sure you get the right system for your home.
🔍 What Does Furnace Size Mean?
“Furnace size” refers to its heating capacity, measured in BTUs (British Thermal Units). This number tells you how much heat the furnace can produce in an hour.
Common residential furnace sizes range from 40,000 to 120,000 BTUs/hour, but the correct size for your home depends on:
Square footage
Insulation quality
Ceiling height
Number of windows and doors
Orientation and sun exposure
Local climate (yes, Ottawa winters count!)
At Clockwork HVAC, we use industry-standard Manual J load calculations to determine the perfect size—not guesswork.
⚠️ What Happens If Your Furnace Is Too Big?
An oversized furnace can heat your home quickly—but that’s not a good thing.
Problems with an oversized furnace include:
🔁 Short cycling (frequent on/off cycles)
❌ Inconsistent temperatures throughout your home
💸 Higher energy bills
🛠️ Increased wear and tear on system components
😟 Shorter system lifespan
🔇 More noise from powerful bursts of airflow
In short, an oversized furnace wastes energy and money—and makes your home less comfortable.
🌀 What Happens If Your Furnace Is Too Small?
On the flip side, a furnace that’s too small for your home will struggle to keep up—especially during the coldest days of the Ottawa winter.
Signs your furnace may be undersized:
It runs constantly but never quite gets warm enough
Some rooms are always colder than others
The system wears out prematurely
You notice rising heating bills
Undersized systems create frustration and can leave you relying on backup heaters when the temperatures drop below freezing.
✅ Why Proper Furnace Sizing Matters
Getting the right-sized furnace for your home means:
☁️ Even, consistent warmth throughout your home
💰 Lower heating bills thanks to better efficiency
🧰 Fewer repairs and longer equipment lifespan
🔇 Quieter operation with less cycling
🌱 Reduced carbon footprint and more eco-friendly performance
Bottom line? You’ll feel more comfortable and confident in your heating system—no matter how cold it gets in Ottawa.
🛠️ How Clockwork HVAC Gets It Right
At Clockwork HVAC, we take furnace sizing seriously. When you work with us, we’ll:
Perform a full heat load calculation
Evaluate your home’s insulation, layout, and heating needs
Recommend high-efficiency furnaces that match your usage
Handle professional installation with care and precision
Provide follow-up support, maintenance, and warranty options
We don't guess—we calculate, test, and deliver comfort that fits.
🏠 Real-Life Example: Furnace Troubles in Kanata
A homeowner in Kanata called us after experiencing constant short cycling and cold spots in their home—even with a brand-new furnace. The issue? Their previous contractor had installed a 100,000 BTU furnace in a home that only needed 60,000 BTUs.
After a proper assessment, we installed a right-sized, energy-efficient furnace—and their home has been cozy, quiet, and cost-effective ever since.
💬 Final Thoughts: Don’t Let Size Cost You Comfort
When it comes to heating your Ottawa home, furnace size matters more than you might think. Whether you’re building new, replacing an old system, or troubleshooting a heating issue, the right fit can make all the difference.
Let the experts at Clockwork HVAC help you choose the perfect system—for your home, your comfort, and your budget.
📞 Call us today or 💻 book a free consultation online to find the furnace that’s just right for your Ottawa home.
