Someone you trust told you their heat pump doesn’t keep their house warm, and now you’re wondering whether the same thing will happen to you. That’s a fair worry, and we’re not going to talk you out of it with reassurance.
Here’s the useful part: in almost every case we’ve been called into, the house being cold has a specific cause that can be named. Six of them come up over and over. None of them is “heat pumps don’t work here.”
It was undersized, because nobody calculated the load
A heat pump has to be matched to how much heat your particular house loses on a cold day. That number is the heat load, and it depends on your insulation, your windows, your air leakage, your square footage and the outdoor temperature the equipment has to hold against.
Metro Vancouver’s winter design temperature is the outdoor temperature the system is designed to handle. In Vancouver and Richmond it’s -7°C under the National Building Code of Canada 2020, and across our service area it ranges from -7°C to about -10°C, colder as you move east and uphill. That’s a mild design condition by Canadian standards, which is exactly why undersizing here is a choice rather than a climate limitation.
The problem is that a lot of equipment gets picked by rule of thumb instead. Someone looks at the furnace that’s being replaced, or at the square footage, and picks a size. If the old furnace was itself oversized, and many are, the replacement inherits the guess. If the house has a poorly insulated crawlspace, and plenty of older homes on the North Shore, in East Vancouver and in Ladner do, the real load is higher than the square footage suggests.
Then the house is fine in October and struggles in January. Not because a heat pump can’t do it, but because nobody worked out what “it” was. Our post on what a heat load report actually is walks through what the calculation involves.
It was oversized, which sounds like it should be safer
This one surprises people. Too much capacity causes comfort problems too, just different ones.
An oversized system satisfies the thermostat quickly, shuts off, drifts, and starts again. That’s short cycling. A heat pump does its best work running at a low, steady output for long stretches, moving a large volume of gently warmed air. When it’s constantly starting and stopping, you get temperature swings, uneven rooms, more noise, and more wear on the equipment.
It’s worth knowing that the sizing argument isn’t just contractors saying it. A City of Vancouver process guide prepared by Dunsky Energy + Climate Advisors makes the same point about oversizing and short cycling, and notes that in their own modelling the smallest available multi-head mini split was already oversized for a typical unit’s load. That’s a document from a party with no equipment to sell.
We’ve written this out in more detail in why you shouldn’t oversize a heat pump.
The ductwork was never looked at
If your friend has a ducted heat pump, this is one of the most common causes and one of the least often checked.
Furnaces produce hot supply air, so a furnace can heat a house through fairly small ducts. A heat pump produces cooler supply air and makes up the difference with volume. It needs to move more air through the same holes. If the duct system was laid out for a furnace decades ago, it may simply be too restrictive.
That shows up as high static pressure, which is the resistance the blower is fighting against. The blower can’t deliver its rated airflow, the far bedrooms get very little, and the house never quite comes up. Meanwhile the room nearest the furnace is fine, so the homeowner assumes the equipment is undersized when the real bottleneck is the path the air takes.
Older Metro Vancouver housing stock makes this more likely, not less. Original trunk and branch layouts in 1950s and 60s bungalows. Additions and finished basements where a run was tapped off whatever was closest and the system was never rebalanced afterward. Flex duct crushed against a joist in a crawlspace that nobody has crawled into in twenty years. A heat pump reveals all of that, because it asks more of the ducts than the furnace ever did.
The backup heat was locked out or set wrong
Most heat pump installs in our climate have some form of backup or supplementary heat, and how it’s configured at commissioning matters as much as the equipment choice.
Commissioning is the setup step after the equipment is physically installed: the point where lockout temperatures, staging, airflow and thermostat behaviour get programmed and verified. It’s where a system either becomes what it was designed to be or quietly doesn’t.
Set the lockout so the backup can’t come on until it’s colder than it ever gets here, and the house falls behind on the few genuinely cold mornings. Set it so the backup fires too eagerly and the heat pump barely gets to do its job. In a dual fuel setup, where a heat pump is paired with a gas furnace, the crossover point between the two is a setting someone chose, and it can be chosen badly.
A house that’s cold on the coldest week of the year is often a configuration problem, not a capacity problem. This is worth asking about specifically, because it’s invisible from the outside.
The thermostat is being used like it’s still a furnace
Deep setbacks make sense with a furnace. A furnace has enormous output relative to the load, so it can claw back 5°C in short order and you save fuel while you’re away.
A heat pump is the opposite. It’s designed to hold a temperature by running long and low. Drop the thermostat 5°C overnight and in the morning the system has to recover a large gap, which usually means calling on backup heat, which is the expensive way to make that heat. Or it recovers slowly and the house feels cold for two hours while it does.
So a homeowner who kept their old habits ends up cold every morning and concludes the heat pump is weak. Set it and leave it, with modest setbacks at most, and the same equipment behaves completely differently. Nobody told them, so it isn’t their fault. But it’s a settings-and-habits fix, not a hardware fault.
Warm air from a furnace and warm air from a heat pump feel different
This last one isn’t a fault at all, and it’s worth knowing before you commit.
Stand at a register with a furnace running and the air feels hot on your hand. Stand at the same register with a heat pump running and it feels warm at best, sometimes close to neutral. The room still gets to temperature. The house is still 21°C. But the sensation at the vent is different, and if you’re used to the furnace blast, the heat pump can feel like it isn’t working.
It also runs for much longer stretches, so people who are used to a furnace cycling on and off notice the fan seems to be on all the time. That’s the system doing what it’s supposed to do.
What we tell homeowners is to judge it by the thermometer and by how even the rooms are, not by how the air feels on your hand at the vent. Once you’ve lived with it through a shoulder season, the long steady heat is usually the part people prefer.
What this means for your quote
Every one of those six is either a design decision, a commissioning decision, or an expectation nobody set. That’s why your friend’s experience doesn’t predict yours.
When you’re comparing quotes, the questions that separate companies are pretty simple. What load did you use to pick this size. Have you looked at my ductwork, and did you measure anything. What will the backup heat be set to do, and at what outdoor temperature. And with a ducted heat pump we size to the block load for the whole house, which is a different calculation than a room-by-room load on a ductless system, so it’s fair to ask which one you’re getting and why.
If a heat pump install qualifies, CleanBC Better Homes and BC Hydro’s Home Renovation Rebate are the programs in play here. Amounts and eligibility change, so check the program sites for current figures. Our starting prices are published, and financing through FinanceIt gets discussed at the quote.
If you’d like us to look at your house and tell you plainly what it needs, book a free, no-obligation assessment or call (778) 800-8868. If your friend’s system is the thing standing in the way, ask them what heat load was used and what the backup lockout is set to. The answers usually explain the whole story.