"Installed means it turns on. Commissioned means it performs."
Peak Comfort HVAC
Ottawa winter is where heat pumps get judged—usually unfairly.
Most “heat pump problems” we hear about in January aren’t the equipment. They’re placement, snow/ice management, airflow, or thermostat settings that were never properly commissioned. This post is the practical checklist: what to do before first freeze, what normal defrost looks like, why the furnace may still run in a hybrid setup, and the few signs that mean it’s time to call.
If you want winter performance you don’t have to babysit, this is the playbook.
Before first freeze (5-minute prep)
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Clear leaves/vines around the outdoor unit; ensure a path for meltwater under the stand.
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Check the stand is level/solid and high enough above typical snow load.
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Confirm thermostat logic for dual-fuel/aux settings.
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Make a snow plan—don’t pile shoveled snow against the unit.
This is the boring stuff that prevents the annoying stuff. Most winter “heat pump failures” we see are actually airflow and drainage problems: snow packed around the coil, ice building where meltwater can’t get out, or a unit that’s slowly shifting out of level.
If you do nothing else: keep the coil breathing and keep the meltwater moving. That’s what keeps defrost normal, reduces ice buildup, and keeps your system from working harder than it needs to.
“My heat pump is steaming like crazy—broken?”
Probably fine. In Ottawa cold, the outdoor coil frosts; the system defrosts by briefly reversing to melt ice. You’ll see steam, hear a tone change, and water will drip and refreeze under the stand. That’s normal. We mount on a proper stand and keep away from walkways so that refreeze isn’t a slip hazard.
Do not chip ice off the coil—bent fins = worse performance. If ice never clears and becomes a solid block, that’s a service call.
"Defrost looks dramatic. It’s usually just the system doing normal winter work."
Peak Comfort HVAC
“Heat dipped for a minute—why?”
During defrost, indoor heat output drops briefly; it should resume after a short cycle. Short pauses (a few minutes) are normal. Persistent no-heat or repeated breaker trips are not—call us.
One mistake homeowners make is thinking the system should feel the same 24/7. In real Ottawa weather, the system will “change gears.” You might notice:
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Warmer air some hours, cooler air other hours (still heating, just lower supply temps).
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A short “quiet period” indoors while the outdoor unit defrosts.
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Longer run times on cold days (that’s normal for high efficiency equipment).
What’s not normal is stuck defrost, rapid cycling, or repeated lockouts. If you’re seeing the same pattern over and over, we’d rather catch it early than after it turns into a block of ice or a no-heat call.
“Why did my furnace turn on?”
In hybrid (dual-fuel) homes, the gas furnace covers the ugly nights and sometimes assists during certain defrost scenarios. That’s by design, not failure—and it’s why we keep natural gas on NG in Ottawa.
The key concept is your balance point: the outdoor temperature where it becomes cheaper (or smarter) to let the furnace take over. That balance point depends on your specific equipment, your ductwork, your home’s heat loss, and your utility rates.
A properly set up dual-fuel system should:
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Run the heat pump most of the season (where it’s efficient and comfortable).
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Hand off to gas when it makes sense (deep cold, or when the heat pump can’t keep up).
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Avoid “fighting itself” (bad thermostat logic can have both systems doing weird things).
If your furnace is coming on a lot during mild weather, that’s usually a settings/commissioning issue—not a “heat pumps don’t work here” issue.
“How should I set my aux/backup so I don’t erase savings?”
Our ROI-first defaults:
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Natural gas: lock out aux above ~–12 to –15 °C (tuned to your equipment curve).
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Propane/Oil: let the heat pump carry deeper cold (≈ –22 to –30 °C, model-dependent).
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Values-first electrification: run HP as far as it can; only switch when it can’t keep up.
"In Ottawa on natural gas, I almost always keep the furnace."
Peak Comfort HVAC
“Which thermostat should I use?”
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Communicating systems: use the OEM communicating stat to keep full modulation.
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24-V hybrids: Ecobee-style is fine when commissioned correctly.
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We avoid Nest: industry-wide pain—weak commissioning tools and power-steal headaches.
The thermostat is the “brain,” and most winter comfort complaints are really brain problems: wrong staging, wrong lockouts, bad sensor placement, or aggressive setbacks.
Two easy homeowner tips:
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Don’t do big temperature setbacks in winter. Heat pumps are efficient when they run steadily; big setbacks often trigger backup heat to “catch up.”
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If your stat supports it, use outdoor temperature display and make sure the outdoor sensor data is accurate (or configured properly through the equipment).
If you’re not sure what you have, we can tell quickly: communicating vs 24V makes a huge difference in how the system should be set up.
“Where should the outdoor unit sit to avoid winter issues?”
On a stand, off the building envelope, decoupled from vibration, above snow load, away from roof-shed and prevailing wind into the coil. Keep it away from walkways (defrost water re-freezes) and away from dryer vents (moist, corrosive air). Maintain clearances and a meltwater path.
The “Ottawa problems” are usually predictable: drifting snow, roof shedding, and refreeze.
What we like to see:
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A stand that’s high enough for real winters (not just the first snowfall).
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A spot where meltwater can drain away, not pool and build an ice pad.
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Placement that avoids roof valleys and downspouts dumping onto the unit.
If your unit sits in a tight corner with nowhere for air or water to go, it will act “mysteriously bad” every cold snap. Good placement makes winter boring—in a good way.
"Winter doesn’t break good heat pumps. Bad setup does."
Peak Comfort HVAC
“What noises are normal vs. not?”
Normal: brief higher-RPM ramps in deep cold; whoosh/steam during defrost.
Not normal: fan hitting ice (scrape), persistent grinding/metallic sounds. Call us.
If you’re unsure, take a 10-second video (sound + visual) and compare it over a few days. Normal sounds are usually brief and repeatable (defrost cycle, ramp up, ramp down). Abnormal sounds tend to be persistent, getting worse, or tied to visible ice contact.
When in doubt: don’t ignore a scraping fan. That’s how a small ice issue becomes a damaged fan motor or bent coil fins.
“What should I check myself in winter?”
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Filters: check monthly in winter; keep airflow up.
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Outdoor: keep sides/top clear; don’t block airflow with snow piles; ensure drain path stays open.
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Visuals: look for sagging insulation, water where it shouldn’t be, or oil staining.
Thermostat basics: keep a steady setpoint, confirm the system mode is correct (Heat / Auto), and don’t force “Emergency Heat” unless you’re troubleshooting or instructed.
Call us now if you see…
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One solid block of ice that never clears
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Fan striking ice / scraping noises
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Breaker trips or repeated resets
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Water inside or condensate where it shouldn’t be
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Burning smells
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Oil staining under/around the unit
Ottawa winters don’t “prove heat pumps wrong.” They just punish weak setup and ignored maintenance.
If you want your system to stay quiet, efficient, and predictable, the formula is simple: good placement + good drainage + correct thermostat logic + real commissioning. If you’re not sure your system is set up that way, we can check it and get it dialed in.
