What I Check Around the House Before the Heat Comes On

Before the heating comes on for the first time, walk the house with a flashlight and a notepad and give yourself thirty minutes. That single pass has saved me a cold weekend, one plumber visit, and the particular smell of dust burning off a radiator with the windows shut. The first genuinely cold night always arrives earlier than I expect, and the difference between a comfortable one and a bad one comes down to a handful of small things done in advance.

My house has radiators and a boiler, and a basement that gets damp in October. Some of what follows is specific to that setup, so I have flagged which parts apply to forced air and which apply to hot water systems. The order is deliberate: the checks that take the longest to fix come first, so if something is wrong you find out while you still have time.

Run the heat once, early, on a mild day

This is the thing to do first, and it is the thing almost nobody does. Pick a mild afternoon in early autumn, open a few windows, and run the heating for twenty minutes.

Two things happen. The dust that settled on the heat exchanger or the radiators over the summer burns off, and it does smell for a while, which is exactly why you want the windows open and a mild day rather than discovering it on the first freezing night. And if something is broken, you learn about it in a week when a technician can come out in a few days, rather than in the first cold snap when everyone in town is calling the same numbers.

I skipped this test one year and then spent four days with a space heater in the bedroom waiting for a part. It is a twenty minute job that removes the worst version of the season.

Filters, vents and radiators

If you have forced air

Change the filter. If you cannot remember when you last did it, that is the answer. Write the date on the edge of the new filter with a marker, because the box it came in will be gone by the time you need to know. Then walk the house and check that no supply or return vent is blocked. Over a summer, furniture moves, a rug creeps, a laundry basket ends up in front of a return, and airflow suffers in ways that are hard to diagnose later.

If you have radiators

Bleed them, starting with the ones furthest from the boiler and working back. Air trapped at the top of a radiator means the top stays cold while the bottom is hot, and you end up turning the whole system up to compensate. You need a bleed key, a cloth, and a small container. Open the valve slowly until the hiss turns into water, then close it. Check the boiler pressure afterwards and top it up if bleeding dropped it below the normal range marked on the gauge.

Also move whatever accumulated in front of them. In my house the radiator in the back room ends up behind a drying rack every summer, and I have to make myself move it in September or it stays there until January.

Where the cold actually gets in

On the walk through, hold the back of your hand near the edges of exterior doors and windows on a breezy day. You will find the drafts faster than any gadget will tell you. Mine are always the same three places: the front door at the bottom, the old sash window on the stair landing, and the letter slot.

• Door bottoms. A draft excluder or a new door sweep is the highest return fix in the whole list. Ten minutes, and you feel it that night.
• Window sashes and frames. Removable weatherstripping along the meeting rail works on old windows without doing anything permanent. Peel it off in spring.
• Letter slots and cat flaps. Small openings that face directly into a hallway move a surprising amount of air.
• Unused fireplaces. If the damper is open, that is a hole in the roof. Close it, and if it does not seal, a chimney balloon does the job.
• Loft hatch. Usually uninsulated and usually leaking warm air upward. Weatherstripping around the frame takes fifteen minutes.

Sealing the gaps around a room does more for how warm it feels than turning the thermostat up by two degrees, and it keeps doing it every night for the rest of the season.

Water is the thing that turns a cold night into a repair bill

Before the first freeze, disconnect and drain the garden hoses and shut off the outside taps at their interior valve if you have one. A hose left connected keeps water sitting in the tap, and that is the classic way a pipe splits. Drain the outdoor tap by opening it after the interior valve is closed.

Pipes running through unheated space, meaning a crawl space, a garage, or against an outside wall in an unheated basement, are worth insulating. Foam sleeves cost very little and cut to length with a knife. I did the run along the basement’s north wall two winters ago and it has not frozen since, though I will admit I have not had a truly brutal winter to test it.

Gutters matter here too, and this is one I put off for years. Blocked gutters overflow, the water runs down the wall or freezes at the edge of the roof, and both of those are worse problems than the leaves were. I clear mine once the trees are mostly bare, which in my case means the first week of November, and I would rather do it in one cold session than twice.

Humidity swings the other way in heating season

Running heat dries indoor air out, and dry air feels colder at the same temperature, which is why people creep the thermostat up. It also cracks wooden furniture, dries skin, and makes static a constant nuisance.

I keep a cheap hygrometer on a bookshelf and aim to stay somewhere in the range where the air is not obviously dry and the windows are not streaming. If it reads low once the heat has been on for a couple of weeks, a small humidifier in the bedroom is enough for me. If it reads high and the windows fog every morning, that is the opposite problem and it means ventilation, not humidification: run the extractor fan longer after showers, and crack a window for a few minutes in the morning even when it feels wrong to let cold air in. Ten minutes of proper air exchange costs very little heat and takes a lot of moisture out.

Safety checks that take four minutes

Heating season is when carbon monoxide risk goes up, because combustion appliances run more and windows stay shut. Press the test button on every smoke alarm and every carbon monoxide alarm in the house. Replace the batteries at the same time every year whether they are complaining or not, so you never have to guess. If you do not have a carbon monoxide alarm near sleeping areas and you have any fuel burning appliance, that is the one thing on this whole page I would deal with today rather than at the weekend.

While you are at it, check that nothing flammable has ended up against a heat source over the summer. Boxes in front of a boiler, a curtain hanging over a radiator, a laundry rack pushed too close.

The soft layer, which is the part you actually notice

Once the mechanical checks are done, the comfort part is quick. Heavier curtains go up, and I close them at dusk rather than at bedtime, because a window loses most of its heat in the hours right after dark. Rugs come back out onto the wood floors in the rooms where we sit, which changes how a room feels underfoot more than anything else I do. Throws move from the storage basket to the arms of the sofa where people will actually pick them up.

My working list, in the order I do it

• Test run the heat on a mild day with windows open.
• Change the filter or bleed the radiators, then check boiler pressure.
• Walk the exterior doors and windows for drafts and fix the worst three.
• Drain and shut off outside taps, insulate exposed pipes.
• Clear the gutters once the leaves are down.
• Test every smoke and carbon monoxide alarm, change batteries.
• Put a hygrometer somewhere you will see it.
• Heavy curtains, rugs, throws.

All of it fits into one weekend morning plus the gutters, and most years I get it done in early October while it is still pleasant enough to be outside. The years I have skipped it, I have not been punished immediately. I have just spent the winter slightly colder and slightly more annoyed, which is its own kind of cost.