What to check before the first cold night
The first genuinely cold night is the busiest day on our calendar — and almost none of those calls are a surprise if you know what to look at in September.
Every year it goes the same way. The Island coasts through a mild stretch, nobody touches the thermostat, and then one night in late October the temperature drops into the thirties. By eight the next morning the phone at 39 Broad Street does not stop.
Here is the thing worth knowing: almost none of those calls are random. The part that fails on the coldest night was already weak in September — it just was not being asked to do anything yet. A boiler that sat idle since April does not announce a cracked low-water cutoff in July. It waits until the night it has to run for nine hours straight.
What actually fails, and why it waits for the cold
On forced-air systems, the two usual suspects are the flame sensor and the capacitor. A flame sensor is a thin metal rod that proves to the furnace that a flame really lit; over a season it builds up a film of oxide, and once that film is thick enough the furnace lights, decides it has not lit, and shuts itself off — over and over. It is a ten-minute clean when someone is looking for it in September, and a no-heat call at 11 PM in January.
Capacitors are worse, because they fail gradually. A capacitor rated at 45 microfarads still runs the blower at 30. It runs it badly, and it runs it hot, and then on the night the system is asked to run all night, it stops. We carry them on the truck for exactly this reason.
On the steam and hot-water side — which is most of the housing north of the expressway — the classic first-cold-night failure is a low-water cutoff that has not been flushed. Sediment settles all summer. The boiler fires, the cutoff reads a water level that is not really there, and the system locks out on safety. That is the system protecting itself, and it is doing its job; it just picks an inconvenient moment.
The twenty minutes that are worth your time
You do not need tools for most of this.
- Run the heat now, for an hour, while it is still mild. This is the single most useful thing on the list. If something is going to fail, you want it to fail on a 60-degree afternoon when the whole borough is not calling at once.
- Change the filter. On forced air, a clogged filter starves the furnace and it overheats and short-cycles — which looks and sounds exactly like a dying furnace and usually is not.
- Walk the radiators. If you are on steam, check that the air vents are not painted over and that every radiator is pitched slightly back toward the pipe. A radiator that is dead flat or tipped the wrong way collects condensate and bangs all winter.
- Look at the flue and the outside vent. High-efficiency units vent through a PVC pipe out the sidewall. Leaves, a nest, or a bush that grew over the summer will shut the system down on a safety switch, and it will look like a serious fault.
- Test the thermostat against a real thermometer. If it is off by a few degrees you have been paying for that all along.
A smell is not always a problem — except when it is
The first time the heat runs each fall, most houses smell faintly of burning dust. That is dust on a heat exchanger burning off, and it clears within an hour. It is normal.
Gas is different, and there is no judgment call to make. If you smell gas, leave the house first. Do not flip switches on your way out — not lights, not the thermostat. From outside, call National Grid at 718-643-4050 and 911. Call us afterward, for the repair. We would far rather quote a repair on a house everyone walked out of than be the second call.
When it is worth having someone look
If the system is over fifteen years old, if you had repairs last winter, or if you have a boiler that has never been serviced since you bought the house, a fall visit pays for itself in one avoided emergency. A maintenance plan covers this automatically — two visits a year, and we call you to schedule rather than the other way around. One of our customers has been on that arrangement for thirty years and says he has had almost no trouble between visits, which is the entire point.
Otherwise, book a heating check before the rush. There is 10% off a fall tune-up on the specials page through the end of November, and the diagnostic fee is quoted on the phone before anyone is dispatched — no number invented at your door.
And if it is already too late and the house is cold: call. We answer until 10 PM, seven days, and no-heat calls jump the line in season. Whether it is a boiler or a furnace, it is work this shop has been doing since 1972.