Short answer: there isn’t a real pause here. New Brunswick’s heating season runs about ten months, and the only quiet stretch, July, sits low enough on the national scale that it counts as a genuine rest for both systems rather than a straight swap from one to the other.
The quietest month in New Brunswick
At the Moncton A weather station, July comes in at about 73 combined degree-days, heating and cooling added together. Across the thirteen provinces and territories this site tracks, that quietest-month figure ranges from roughly 45 up to about 233. Seventy-three sits well down in that range, closer to the calm end than the busy one.
Degree-days measure demand, not temperature. A day with a low degree-day count isn’t necessarily a mild day outdoors; it’s a day when the gap between the indoor comfort target and the outdoor air is small enough that neither the furnace nor the air conditioner has much reason to run. That distinction matters here, because a low July total doesn’t describe a hot Maritime summer. It describes a month when the house, for once, isn’t asking for much of anything.
That’s the real value of the number: with New Brunswick landing near the bottom of the national range, July functions as an actual pause rather than a changeover squeezed into a single week. The heating season has wound down by then, and the cooling season, such as it is here, never ramps up hard enough to fill the gap. Reference-station data for Moncton puts the average number of days a year reaching 90°F or hotter at zero. There’s essentially no sustained heat load pushing air conditioners into daily service, which is part of why so much of the province gets by without central cooling at all.
What that means for the thermostat
Practically, this is the stretch when both systems can sit idle without anyone noticing. It isn’t a week. It’s closer to a season within the season, bookended by a heating year that starts building again in September and a cooling need that, for most homes, barely registers even at its peak. Compare that to provinces at the high end of the 45-to-233 range, where the “quiet month” is really just the hinge between two demanding seasons with no slack in between. New Brunswick has slack. July is where it lives.
Shutting the heat down for the year
The shutdown at the end of the heating season is less about flipping a switch and more about letting the system stand down in the right order. Rushing it, or doing it backwards, is how a forgotten step turns into a fall repair call.
- Stop calling for heat at the thermostat first, not at the breaker or the fuel valve. Let the control system register that heat isn’t needed rather than cutting power to it mid-cycle.
- Let the system finish whatever cycle it’s already running. Fans and blowers that stop abruptly mid-cycle don’t clear residual heat the way they’re designed to.
- Anything involving combustion, gas valves, pilot assemblies, venting, follows the manufacturer’s guidance and nothing improvised. This is where a homeowner’s checklist should stop and a qualified technician’s should start.
- Inspect, clean, or change the filter. U.S. ENERGY STAR is direct about the schedule: “Inspect, clean, or change air filters once a month in your central air conditioner, furnace, and/or heat pump.” The seasonal changeover is a natural moment to do this, but it isn’t a substitute for doing it monthly the rest of the year.
- If there’s a humidifier attached to the ductwork, shut it down now. It’s one of the most commonly forgotten steps in a fall-to-summer changeover, and a humidifier still calling for moisture into a duct system that’s no longer moving warm air can cause its own problems.
- Clear the physical space: vacuum registers and baseboard covers, move furniture and curtains back from any heat sources, and check that nothing’s been stacked against a unit over the winter.
One caution specific to this province: heating demand here runs about ten months of the year, according to the degree-day pattern at Moncton A, with only a brief true lull around midsummer. That’s not a place where it makes sense to disable a heating system entirely for the season. Keep it capable of responding if a late-spring or early-fall cold snap comes through, rather than shutting it down as if the province had a long, reliably mild summer to spare.
The first run of the cooling season
Do this on a mild day, not the first genuinely hot one. A mild day means if something’s wrong, whether it’s a clogged condensate line, a filter nobody remembered, or a unit that just won’t kick on, there’s time to deal with it calmly instead of living without cooling during the first heat wave of the year.
- Clear the outdoor unit and the ground around it: leaves, grass clippings, anything that’s built up against the housing over the winter and spring.
- Check the condensate path. A blocked drain line is one of the more common causes of a system that runs but doesn’t cool properly, or that leaks where it shouldn’t.
- Change or wash the filter. This is the same step from the shutdown checklist, and it applies going into cooling season exactly as it applied going into heating season.
- Run the system in COOL for a full cycle on that mild day, not just for a minute to confirm it turns on.
- Feel the air at a register farthest from the unit, not the nearest one. Weak airflow at the far end of the house shows up there first.
ENERGY STAR puts a number on why that airflow check matters: “Airflow problems can reduce your system’s efficiency by up to 15 percent.” A system can be mechanically sound and still underperform badly if airflow is restricted somewhere along the line.
What this looks like locally depends heavily on what’s actually installed. Statistics Canada’s most recent household survey puts air conditioning ownership in the Atlantic region at 58.9 percent, against 68.3 percent nationally, that’s a regional figure, not a New Brunswick-specific one, but it signals that a meaningful share of homes doing this seasonal check are working with a window unit or a portable unit rather than a central system. For those, the checklist shrinks: clean the unit, check the seal around the window frame, and confirm it starts and holds a set temperature before the first hot stretch arrives.
The days that ask for both
Every homeowner in a cold-winter province knows this week: heat runs at six in the morning because the house dropped overnight, and by mid-afternoon the same house is calling for cooling because the sun’s come around and the afternoon’s warmed up. It happens in the transition weeks on both ends of the calendar, and it’s rarely explained anywhere.
One useful way to think about it: a month “asks for both” when it carries at least 50 heating degree-days and at least 50 cooling degree-days. That threshold isn’t a published NOAA or Environment Canada category, it’s a convention used here to describe a pattern, not an official cutoff. With July at Moncton A sitting around 73 combined degree-days and with essentially no days reaching 90°F in an average year, New Brunswick’s double-demand stretches are more likely to show up at the edges of spring and fall, when mornings are still cool and afternoons have started to warm, than in the height of summer itself.
| What to do | Why it matters |
|---|---|
| Switch the thermostat off HEAT/COOL auto-changeover manually when a swing week hits | Auto mode reacts to both calls, but on a narrow setpoint gap it can heat the morning air and then cool that same air a few hours later, running both systems for a day that needed neither for very long. |
| Widen the deadband between the heating and cooling setpoints | A wide gap, several degrees, lets the house drift naturally between the two calls instead of triggering one system right after the other finished with the same air. |
| Open the windows instead, when outdoor conditions allow it | On the exact days that ask for both, a morning window open and an afternoon window closed often does the job that two separate systems would otherwise handle, at no operating cost. |
The expensive version of this mistake is a narrow gap between setpoints left on auto through the whole swing season: the furnace heats the house at 6am to hit 68°F, and by 2pm the air conditioner is cooling that same air back down to 72°F. Widening the gap, or just switching to one mode manually for the day, avoids paying twice for the same few degrees.
And the changeover in the other direction
New Brunswick’s heating season starts building again earlier than a lot of homeowners expect. September is the first month here where the average mean daily temperature, about 13.6°C, drops back below the 18°C threshold used to count heating degree-days. Demand climbs through the fall and peaks in January at roughly 832 degree-days, before easing back down and finally dropping under that 18°C line again in July.
What that fall pre-season check should focus on depends on what’s actually heating the house. Provincial data on primary heating systems shows electric baseboard heaters in 31 percent of homes and heat pumps in 27 percent, with forced-air furnaces at just 9 percent. Boiler systems and wood stoves aren’t published with a reliable figure in that same survey, which means the data was suppressed as unreliable, not that nobody uses them.
That mix changes the fall checklist. Heat pump households are really running one system with two seasonal checklists, the cooling-side steps above and the equivalent heating-side ones, back to back. Baseboard households have a shorter list: clear furniture and drapes from in front of every heater, vacuum the fins, and confirm nothing’s been stacked against them since spring. The full furnace-specific pre-season routine, useful for that smaller share of homes running forced air, belongs on this site’s dedicated heating-season guide rather than repeated here.