How to Lower Heating and Cooling Bills in Ottawa

Quick answer: To lower heating and cooling bills in Ottawa, set back the thermostat at night and when away, change the furnace filter regularly, seal drafts in the attic and basement, book yearly tune-ups, and keep indoor humidity right. If your furnace is 80% AFUE or your AC is over 15 years old, upgrading usually saves the most.

Key takeaways

Free

Thermostat setbacks, fan on Auto, blinds and curtains used by season, clear vents.

Under $50

Furnace filters, weatherstripping, caulking and foam gaskets on outlet covers on outside walls.

Under $600

A yearly tune-up ($120 – $200 per system) and a smart thermostat ($250 – $600 installed).

Bigger wins

Attic insulation, sealing rim joists, and replacing an 80% AFUE furnace or old AC.

Rebates may be available

For some upgrades. Oria will check current programs for your home.

Where your money goes

In most Ottawa homes, space heating is the single largest energy cost, paid to Enbridge Gas for natural gas furnaces and boilers, or to Hydro Ottawa for electric heat and heat pumps. Summer cooling shows up on your hydro bill and peaks during July and August humidex spells.

The good news is that the same few things lower both: a tight house, clean equipment and smarter thermostat settings. Start with the free and cheap steps, then decide on upgrades with real numbers.

Winter: how to lower heating bills

1. Set back the thermostat

Lowering the temperature by 3–4 °C overnight and while everyone is out reduces how long the furnace runs. A smart or programmable thermostat does this automatically and warms the house before you wake up. Avoid huge setbacks if you have a heat pump, since recovering from a deep setback can call on backup electric heat.

2. Change the filter and book a tune-up

A clogged filter makes the blower work harder and the furnace run longer. Check it monthly from December to February. A fall tune-up cleans the burners and flame sensor, checks the blower and confirms safe combustion. Our furnace maintenance checklist lists what should be done.

3. Seal the leaks you can feel

Cold air sneaks in through the attic hatch, basement rim joists, dryer and bathroom vents, window frames and electrical outlets on outside walls. Weatherstrip the attic hatch, caulk window trim and spray-foam the rim joist in an unfinished basement. Those are some of the cheapest upgrades in a 1970s or 1980s Ottawa home.

4. Keep humidity in range

Air at 30–35% humidity feels warmer than dry air at the same temperature, so you can be comfortable at a lower setpoint. Lower it on the coldest days to avoid window condensation. Our guide to ideal indoor humidity in Ottawa winters has a simple chart.

5. Use the sun and the curtains

Open south-facing blinds on sunny days and close heavy curtains at night. Close the damper on a wood fireplace when it is not in use; an open damper is like a window left open.

6. Clear vents and returns

Keep furniture and rugs off supply registers and return grilles. Closing vents in unused rooms does not save much in a forced-air system, and closing too many can raise duct pressure and strain the blower.

Summer: how to lower cooling bills

1. Use moderate setpoints

Set the thermostat around 24–25 °C when home and a few degrees higher when away. Every degree warmer means shorter run times. Avoid turning the AC off completely during a heat wave; the house soaks up heat and humidity and takes hours to recover.

2. Pre-cool before peak hours

If you are on a time-of-use or ultra-low overnight electricity plan, cool the house a little more before weekday on-peak hours, then let the temperature drift up slowly. Smart thermostats can schedule this for you.

3. Fan on Auto, not On

Running the blower non-stop uses electricity and pushes moisture from the coil back into the air, which makes you feel warmer and turn the thermostat down.

4. Block the sun

West- and south-facing windows are the biggest source of afternoon heat gain. Close blinds or shades by noon, and consider exterior shading or solar film on large patio doors.

More summer savings

Clean the outdoor unit.

Cottonwood fluff, grass clippings and leaves block the condenser coil. Rinse it gently with a garden hose with the power off, and keep shrubs 45–60 cm away on all sides.

Book an AC tune-up in spring.

A technician checks refrigerant charge, cleans the coil and tests the capacitor before the first heat wave. See our AC maintenance and home cooling tips.

Use ceiling fans counterclockwise.

The breeze lets you feel comfortable 1–2 °C warmer. Turn fans off in empty rooms.

Cook outside.

Use the BBQ, microwave or slow cooker on hot days instead of the oven.

Dry the basement.

A dehumidifier in a damp basement makes the whole house feel cooler.

Open windows on cool nights.

When it drops below about 18 °C and the air is not muggy, turn the AC off and ventilate.

Savings strategies compared

Strategy	Season	Typical cost	Effort
Thermostat setbacks	Both	Free	Low
Filter changes	Both	Low (filters)	Low
Weatherstripping and caulking	Both	Low	Low to medium
Furnace or AC tune-up	Fall / spring	$120 – $200 per system	Book it
Smart thermostat	Both	$250 – $600 installed	Low
Attic insulation and air sealing	Both	Varies by home	Contractor
High-efficiency furnace (96–98% AFUE)	Winter	$4,500 – $8,500	Contractor
New central air conditioner	Summer	$4,000 – $8,000	Contractor
Ducted cold-climate heat pump	Both	$9,000 – $18,000	Contractor

Prices are typical Ottawa installed ranges before rebates. The final price depends on the home, the equipment and the venting and ductwork. Oria gives free quotes on any equipment purchase.

Upgrades that pay back the most

Replace an 80% AFUE furnace

A mid-efficiency furnace wastes about 20 cents of every gas dollar out the chimney. A new 96–98% AFUE furnace wastes 2–4 cents. If your furnace has a metal flue into a chimney instead of white PVC pipes out the wall, it is likely mid-efficiency. A variable-speed blower also uses much less electricity than an older blower motor.

Replace an aging AC, or switch to a heat pump

Air conditioners lose efficiency with age, and an old unit can use noticeably more power than a modern SEER2-rated model to cool the same house. If your AC is due, a cold-climate heat pump can cool in summer and carry much of the heating load in spring, fall and milder winter days, with your furnace as backup. Our guide to gas furnace vs heat pump compares running costs.

Ventilate smart

An HRV recovers much of the heat from stale exhaust air before sending it outside, so tight homes get fresh air without throwing heat away.

Rebates may be available for some upgrades through current Ontario programs. Oria will check what applies to your home; see our HVAC rebates page.

Get a plan for your home

Oria has helped Ottawa homeowners cut energy waste since 2014, from simple tune-ups to full system upgrades. Book a tune-up through our HVAC maintenance plans, or ask for a free quote on a high-efficiency furnace, AC or heat pump. Call (613) 866-1869. Financing is available from $49/month on approved credit.

Frequently Asked Questions

What temperature should I set my thermostat in winter to save money?

Many Ottawa households are comfortable around 20–21 °C when home and awake, and 16–18 °C overnight or when away. A smart or programmable thermostat can make these changes automatically and warm the house before you wake up. With a heat pump, use smaller setbacks of 1–2 °C to avoid triggering backup electric heat during recovery.

What temperature should I set my AC to in summer?

Around 24–25 °C when you are home is a good balance of comfort and cost, with a few degrees higher when the house is empty. Keep the fan on Auto so the AC removes more humidity. During a heat wave, avoid turning the AC off entirely, because the house absorbs heat and moisture and takes hours to cool again.

Does a smart thermostat really lower energy bills?

A smart thermostat lowers bills by automating setbacks you might otherwise forget, adjusting when you leave or return, and showing how long your system runs. Savings depend on your habits; if you already adjust the temperature manually every day, the gain is smaller. Installed cost is typically $250 – $600 in Ottawa, and rebates may be available.

Is it cheaper to leave the heat on or turn it off when I leave?

Turning the heat down, not off, is cheaper. A setback of 3–4 °C while you are out reduces run time, and the furnace easily recovers when you return. Turning the heat completely off in an Ottawa winter is risky because pipes on outside walls can freeze, and the house takes much longer to warm back up.

How much can a new furnace lower my gas bill?

Replacing an 80% AFUE furnace with a 96–98% AFUE model cuts the fuel lost up the chimney from about 20% to 2–4%, so your gas use for heating drops noticeably. Actual savings depend on your home’s size, insulation and gas rates. A high-efficiency furnace typically costs $4,500 – $8,500 installed in Ottawa.

Do HVAC tune-ups actually save money?

Yes. A tune-up cleans burners, flame sensors and coils, checks airflow and refrigerant charge, and catches worn parts before they fail. A clean, properly adjusted system runs shorter cycles and lasts longer. In Ottawa, a tune-up typically costs $120 – $200 per system, which is often less than one emergency service call.