There’s a moment every September in Ottawa that feels the same every year.
The air changes. Evenings get sharper. You notice you’re reaching for a sweater instead of a T-shirt, and at some point you ask yourself:
“Is it time to turn the furnace on yet?”
Maybe you’re trying to hold off a little longer to save energy. Maybe you’re a bit nervous because the furnace has been sitting idle since spring. Or maybe you remember a strange smell or noise from last winter and you’re wondering what you’ll hear when it fires up again.
At Noah’s Home Comfort, we help homeowners make that first start-up of the season feel calm, safe, and predictable—not stressful. In this blog, we’ll walk you through:
- When it makes sense to turn the furnace on
- What you should check before that first start
- Which smells and sounds are normal (and which aren’t)
- When it’s time to schedule a proper fall furnace inspection
Our goal is to help you feel confident about your heating system before the real cold arrives.
When Is the “Right” Time to Turn Your Furnace On?
There’s no single date on the calendar when everyone in Ottawa has to turn on their furnace. Instead, we like to think in terms of comfort, safety, and practicality.
Watch the Weather and Your Home’s Habit
In September and early October, temperatures can swing:
- Warm during the day
- Quite cool overnight
- Big differences between sunny days and rainy stretches
You might start thinking about heat when:
- The house feels chilly in the morning and doesn’t really warm up on its own
- People are layering up or using blankets around the house most of the day
- Bedrooms feel cold enough that sleep is affected
A good rule of thumb is this: if your home regularly feels uncomfortable for more than a day or two in a row, it’s reasonable to test and start using your furnace.
Don’t Wait Until the First Deep Cold
We don’t recommend waiting until:
- Night-time temperatures are already near or below freezing
- You wake up and your home feels much colder than you expected
- Everyone in the city is turning their heat on at the same time
Turning your furnace on for a short test run in September is often the best approach. It gives you time to:
- Make sure it starts properly
- Notice any smells or noises
- Schedule service or repairs while the weather is still relatively mild
Think of early use as a systems check rather than a full switch to “winter mode.”
Step 1: Check and Change Your Furnace Filter
Before you even touch the thermostat, we strongly suggest checking the furnace filter.
Why the Filter Matters So Much
A dirty filter can:
- Restrict airflow through the system
- Make your furnace work harder than it needs to
- Reduce comfort in certain rooms
- Contribute to poor indoor air quality
If it’s been many months since you changed the filter—or you honestly can’t remember when it was last replaced—it’s safest to start the season with a fresh one.
What We Recommend
We can help you:
- Identify where the filter is located in your specific system
- Choose a filter type that balances good filtration with strong airflow
- Set a realistic schedule for replacing or cleaning filters through the heating season
Starting the fall with a clean filter is one of the simplest, most effective steps you can take for your furnace.
Step 2: Set and Test Your Thermostat
Next, go to your thermostat.
Switch From Cooling to Heating
If you’ve been running air conditioning, you’ll need to:
- Change the mode from Cooling (or “Cool”) to Heating (or “Heat”)
- Set the temperature a few degrees higher than the current room temperature so the heat will actually come on
If you have a programmable or smart thermostat, this is also a good time to:
- Review your schedule and adjust it for new routines (like kids back in school, working from home, or different wake/sleep times).
- Turn off or adjust any summer-specific programs you set up earlier.
Listen for the System Starting
Once you call for heat, pay attention to:
- Does the furnace start up within a reasonable time?
- Do you hear the usual sequence—fan, burner, airflow through vents?
- Are there any unusual delays or repeated attempts to start?
If nothing happens, or if the furnace keeps trying and failing to start, that’s a sign you should turn it off and call us for a closer look.
Step 3: Expect a Slight Smell—But Know What’s Normal
One of the most common concerns during the first furnace start in fall is smell.
What’s Usually Normal
It’s actually quite common to notice a light “dusty” or warm smell when you first turn on the furnace after several months. Over the summer, a thin layer of dust can settle on:
- Heat exchanger surfaces
- Internal components
- Ductwork and registers
When the furnace runs for the first time, that dust can burn off and create a temporary odour.
In many cases, this:
- Is mild
- Fades after a short period
- Does not return once the system has been running regularly
You can support this process by:
- Making sure windows can be opened briefly, if outdoor conditions allow
- Keeping an eye on the smell and confirming it gets better, not worse, after a short time
When Smell Is a Concern
Turn the system off and call us if you notice:
- A strong burning or electrical smell that doesn’t go away quickly
- A smoky odour inside the home
- Any smell that seems sharp, unusual, or worrying rather than just lightly dusty
If you ever suspect a gas leak or smell something like rotten eggs, leave the home and contact the appropriate emergency line immediately—then call us once things are safe.
Step 4: Listen for Unusual Noises
Your furnace will make some familiar sounds as it operates, but it shouldn’t sound alarming.
Sounds That Are Usually Normal
Many systems will have:
- A gentle whoosh of air from vents
- A steady hum from the blower fan
- A brief sound of ignition at start-up
If you’ve had the furnace for a while, you probably know what its “normal voice” sounds like.
Sounds That Need Attention
Call us if you notice:
- Banging or clanging noises (beyond the occasional minor duct “pop” when metal expands)
- Grinding or screeching sounds from the blower or motor areas
- Loud rattles or vibrations that weren’t there last year
- Repeated clicking without successful ignition
These can be signs of:
- Loose components
- Worn motors or bearings
- Ignition or burner issues
- Airflow restrictions or duct problems
Catching these early, during your first start-up, gives us a chance to correct them before you’re relying on the furnace full-time.
Step 5: Walk the House and Check the Heat Distribution
Once the furnace has been running for a little while, it’s a good idea to walk through your home and see how it feels.
What to Look For
- Are vents blowing warm air in main living areas?
- Do bedrooms receive a reasonable amount of warm air?
- Are any rooms noticeably colder or hotter than others?
- Are vents blocked by furniture, rugs, or curtains?
You can often improve comfort just by:
- Opening registers that were closed in the summer
- Moving furniture away from vents and returns
- Making sure doors are open in rooms you want to heat
If you still see big differences in comfort between rooms or floors, that’s something we can assess more deeply—often by looking at duct balance and airflow.
Step 6: Early Warning Signs You Shouldn’t Ignore
As you start testing and using your furnace in September, pay attention to signs that something may need professional attention.
Call Us If You Notice:
- The furnace frequently turns on and off in short bursts (short-cycling).
- The system is running constantly but the home still doesn’t feel warm.
- You hear repeated ignition attempts or see error codes on a display.
- Your carbon monoxide (CO) detector goes off (in which case, leave the home and contact emergency services first).
- You see water around the furnace, especially in systems with condensate drains.
These are all indicators that a fall furnace inspection or repair visit is needed before you rely on the system for cold nights.
Step 7: Why a Fall Furnace Inspection Is Worth It
Even if your furnace seems to start and run “okay,” a professional fall inspection and maintenance visit can make a big difference.
When we perform a fall furnace check, we typically:
- Inspect key components for wear, damage, or safety concerns
- Check and clean burners and ignition systems, where applicable
- Verify venting and exhaust paths are clear and properly configured
- Test safety controls and limits
- Look at airflow and filter setup
- Listen to how the system runs under normal load
Our goals are to:
- Reduce the chance of mid-winter breakdowns
- Improve efficiency, so you’re not wasting energy
- Help your furnace run more quietly and consistently
- Keep your home safer by ensuring combustion and venting are behaving as they should
September and October are ideal months to schedule this work—before temperatures really drop and the busiest service weeks arrive.
Step 8: Get Ahead of the Season Instead of Reacting Later
A lot of furnace problems show up for the first time on the first truly cold night. That’s when:
- The system has to run longer and harder
- Small issues that were barely noticeable become major ones
- Many homeowners call at once with “no-heat” emergencies
By turning your furnace on early, checking the basics, and scheduling a fall inspection, you can:
- Catch issues while there’s still time to make calm decisions
- Avoid waking up to a cold house on the first frosty morning
- Head into late fall and winter with confidence instead of worry
We think of it as taking the surprise out of heating season.
Call to Action
If you’re approaching that “first chill” moment and wondering when to turn your furnace on, or you’ve already tried and something doesn’t feel quite right, we’re here to help.
Call Noah’s Home Comfort at (343) 227-6992 or email info@noahhomecomfort.com to schedule a fall furnace inspection and start-up check. We’ll look over your equipment, test its operation, and make sure your heating system is ready long before Ottawa’s real winter weather arrives.
