Some heating and cooling advice gets repeated so often that it stops sounding like a claim and starts sounding like common sense. A few of those beliefs are quietly expensive. Here are five we hear most often in Montreal and Laval homes, and what is actually true.
Myth 1: Setting the thermostat higher heats the house faster
It does not. A thermostat is a target, not a throttle. Your system produces heat at one rate whether you ask it for 21 or for 26. Turning the dial higher does not speed anything up. It simply keeps the system running past the point where you were already comfortable, so the house overshoots and you pay for heat you did not want.
The same is true in reverse with air conditioning in summer. If a room is slow to reach temperature, the cause is usually airflow, sizing or insulation rather than the number on the wall. Our guide to optimizing a central heat pump covers the settings that genuinely make a difference, including why large setbacks work against a heat pump.
Myth 2: Maintenance is not necessary as long as your HVAC system is working
Equipment rarely fails suddenly. It degrades. A clogged filter, a dirty coil or a tired fan makes the system work harder for months before anything actually stops, and you pay for that extra effort on every bill in the meantime. By the time a system fails outright, it has usually been costing you money for a long while.
Skipping maintenance can also cost you the warranty. Most manufacturers expect documented annual servicing, and a claim can be refused without those records. We recommend two visits a year, one before the cooling season and one before the heating season. What normal HVAC maintenance includes sets out what each visit covers, and how to prepare your furnace for winter deals with the heating side specifically.
Myth 3: A heat pump stops working below −15 °C
Cold-climate heat pumps keep producing heat well below that. This belief comes from older equipment and has not reflected reality for years. What does change with the cold is capacity. The lower the temperature, the less heat the unit can deliver, which is exactly why correct sizing and a sensible backup plan matter so much in Quebec.
That is a design question rather than a reason to rule out a heat pump. Is a central heat pump enough for a Quebec winter? looks at where the real limits sit, and how a heat pump works explains why it can deliver more heat than the electricity it draws. If you already own a furnace, a bi-energy setup pairs the two so each one runs when it makes the most sense.
Myth 4: Electric heating costs more than gas in Quebec
This one travels here from places where electricity is expensive. Quebec is not one of them. Electricity here is comparatively inexpensive, which changes an arithmetic that genuinely does hold true across much of North America. Advice written for another market does not automatically apply to a house in Laval.
The comparison also tends to be framed the wrong way. A heat pump does not burn electricity to create heat the way a baseboard does. It uses electricity to move heat that is already there, so each unit of electricity delivers several units of warmth into the house. That is a different equation from fuel against fuel. Our comparison of home heating methods sets the options side by side, and converting to electric heating covers what a switch actually involves.
Myth 5: A lower quote means the same work for less
A lower price usually buys a different standard of work, not the same work at a discount. Two companies quoting the same house can be proposing genuinely different jobs. One includes a heat load calculation, correctly sized and sealed ductwork, a measured refrigerant charge and a commissioning check at the end. The other works from an educated guess and whatever can be finished in a day.
That difference does not announce itself on installation day. It shows up over the years that follow. An oversized system short cycles, never runs long enough to dehumidify properly and wears its components out faster. Restricted airflow or an incorrect charge makes a unit work harder than it was designed to, so your bills sit higher the whole time and the compressor moves steadily toward an early failure. The name on the equipment can be identical in both quotes. The performance you actually live with will not be. Manufacturers rate their equipment installed correctly, and correct installation is the only condition under which you ever see those numbers.
The equipment itself often differs more than the quotes suggest. Two proposals can name the same brand while offering very different units: single-stage against variable-capacity, different sound levels, different expected service life, and warranty terms that vary in how long labour is covered rather than just parts. A quote that is cheaper because the labour warranty is shorter is not cheaper, it is a bet on nothing going wrong.
So compare the inclusions line by line, ask what the sizing calculation actually produced, and check who stands behind the labour. How to choose an HVAC contractor covers the questions worth asking, and our central heat pump buyer’s guide explains why the sizing step is the one you should never see skipped. Good installation also keeps paying through regular maintenance. If budget is the real constraint, financing is a better lever than a thinner scope of work.
Still not sure?
Most of these myths survive because the truth takes a sentence longer to explain than the myth does. If you are weighing a decision and would rather have a straight answer about your own house than a general rule, get in touch. We work across Montreal and Laval, and we are just as happy to tell you when you do not need what you were about to buy.
