FirstCheck
EN FR
🍁 Conçu pour les foyers canadiens — rédigé selon le Code canadien de l’électricité et les règles provinciales. N’est pas destiné à un usage hors du Canada.
ÉBAUCHE — cette page n’a pas encore été révisée par un professionnel licencié. Aperçu éditorial seulement.

Half the house has no power

Unsettling, but often simple: when only part of the house goes dark, the usual cause is a single tripped breaker you can reset in a minute — no tools, no cost.

tuneQue remarquez-vous?
Sélectionnez ce qui correspond et la liste ci-dessous se réordonne. Pas certain? Passez.
emergency_home

flag
Commencez ici

In Canada, start at the electrical panel. Open the door and look along the row of breakers for one whose handle sits between ON and OFF, or is not pushed fully to ON. That one has tripped. Firmly switch it fully OFF, then back ON. If it holds, you're done — this is the most common fix and it's free.

Classé selon des données de pannes réelles. L’ordre s’ajuste selon vos observations ci-dessus.

Causes probables, dans l’ordre à vérifier

Ordre typique affiché
Pour débutant Faisable, avec soin Sécurité critique Appelez un pro

visibilityHow to check

  1. Open the panel door (the outer cover with the breaker handles showing — you are not removing any screws or the inner dead-front cover).
  2. Scan the breakers. A tripped one usually sits in a middle position between ON and OFF, or feels loose compared to its neighbours; some have a small orange or red flag showing.
  3. Note which circuit it is and what rooms went dark to confirm they match. If nothing looks tripped, the trouble is likely the main, the neutral, or the utility — see those sections.
buildAucun outil schedule5 min

handymanHow to fix it

warning Reset once — never over and overA breaker trips to protect the circuit from an overload or a short. Resetting it once is fine. But if it trips again, do not keep forcing it back on: repeated resets on a real fault can overheat wiring and start a fire. If it won't stay on, leave it OFF and call a licensed electrician. And if the breaker feels warm, smells hot, or is scorched, don't touch it — that's the failing-panel case, not a simple reset.

Fully switch the tripped breaker OFF, then back ON, one time. If it holds, power is restored. If it trips again immediately or won't stay on, stop resetting it and call a licensed electrician — a breaker that keeps tripping is doing its job on a real fault.

  1. Push the tripped breaker firmly to the full OFF position first — this resets its internal mechanism; flipping straight to ON often won't catch.
  2. Now switch it firmly to ON. You should feel it seat solidly.
  3. Check that the affected rooms have power. If the breaker holds, you're done. If it trips again right away, leave it OFF and call a licensed electrician — do not keep resetting it.
schedule5 min savingssouvent gratuit

verifiedPourquoi confier ceci à un pro

A loose or lost neutral lets the voltage on your circuits swing far above normal, which can destroy electronics and start a fire, and the connections involved are lethal to touch. Opening the panel to "check" is not a homeowner task under any circumstances. Unplug sensitive electronics, keep the panel closed, and call a licensed electrician. If it makes you nervous, that instinct is correct.

Vos notes accompagnent la demande — ce que vous avez vu, ce que vous avez éliminé, quand ça a commencé — pour que le pro arrive avec une longueur d’avance.

visibilityHow to check (safely, without touching anything)

  1. Ask whether neighbours have full power. If several homes are affected the same way, the problem is on the utility's side, not yours.
  2. Think back to when it started — right after a storm, a bang, or crews working on the lines points upstream to the service drop or transformer.
  3. Do not open the meter socket or service equipment. If it looks utility-side, call your electricity utility's outage or emergency line and report a lost leg / partial power.
buildAucun outil schedule5 min

verifiedPourquoi confier ceci à un pro

The service drop, meter, and transformer belong to and are maintained by your electricity utility. Do not open the meter socket or attempt any work on the incoming service — it stays energized even when your main breaker is off. If the fault is upstream of your panel, call your utility's outage or emergency line and let them restore the leg.

Vos notes accompagnent la demande — ce que vous avez vu, ce que vous avez éliminé, quand ça a commencé — pour que le pro arrive avec une longueur d’avance.

verifiedPourquoi confier ceci à un pro

The main breaker and bus bars stay energized from the utility side even with the main switched off — there is no way for a homeowner to make them safe to work on. Diagnosing or replacing a failed main or bus means working live or coordinating a utility disconnect. In Canada this is a licensed electrician's job; a technician can confirm and quote it quickly.

Vos notes accompagnent la demande — ce que vous avez vu, ce que vous avez éliminé, quand ça a commencé — pour que le pro arrive avec une longueur d’avance.

sort

Pourquoi la liste est dans cet ordre

Nous ne classons pas seulement selon la probabilité. Nous classons comme le ferait un bon artisan honnête : éliminer d’abord les causes gratuites, sûres et courantes. C’est pourquoi les vérifications peu coûteuses passent avant les réparations chères — et pourquoi tout ce qui est dangereux reçoit un arrêt net plutôt qu’un encouragement. Cet ordre existe pour vous faire économiser, pas pour vous vendre quelque chose.