Partial Power Outage in Hamilton: 7 Checks Before You Call

By Zvonko Lipovac, Master Electrician, Apollo Electric Inc. · ECRA/ESA 7009372 · Last updated: 6 September 2026

A partial power outage is the one fault that sends Hamilton homeowners straight to the wrong phone number. The utility gets called for a problem inside the house, or an electrician gets called out at midnight for a breaker that a homeowner could have reset. Five minutes of checking tells you which it is.

Apollo Electric Inc. has diagnosed this fault in Hamilton homes for over 30 years, under ECRA/ESA licence 7009372. If you are still choosing who to trust with it, our guide to hiring a licensed electrician in Hamilton sets out the four checks that matter, and the wider rules are on our electrical safety page. This page walks the same sequence we walk on the phone.

What a Partial Power Outage Usually Means

When some rooms work and others do not, current is still entering the house. Something between the panel and those rooms has opened. There are only four realistic causes, and they sit in a clear order of likelihood.

The last two matter most. A partial power outage caused by a loose connection is not a nuisance, it is a fire risk that has started announcing itself.

What to Check, in Order

Work through these in order the moment a partial power outage starts. Everything below is safe for a homeowner, and nothing here involves opening the panel cover.

1. Look outside first. Streetlights on and neighbours lit means the problem is inside your house. A dark street is a grid event, and only Alectra Utilities can restore that. Their line is 1-833-253-2872, staffed 24 hours a day.
2. Check the GFCI outlets. Bathrooms, kitchen counters, garage, basement and any outdoor outlet. Press reset firmly. One tripped GFCI can kill outlets in three rooms, and this is the single most common false alarm we get called out for.
3. Open the panel door, not the cover. The door with the breaker directory is safe to open. The inner cover with the screws is not, ever.
4. Look for a breaker out of line. A tripped breaker often sits slightly off from its neighbours rather than fully off. To reset it, push it firmly to off first, then back to on.
5. Reset once, and only once. If it trips again straight away, stop. Something on that circuit is faulted, and repeated resetting is how a fault becomes a fire.
6. Count what is dead. One room points at one circuit. Half the house points at a lost leg, which is a different problem and a more urgent one.
7. Check for heat and smell. A warm faceplate, a scorch mark or a burning smell changes this from troubleshooting to an emergency. Stop and call.

If steps one to five restore power and nothing trips again, you are done and you do not need us. That is the honest answer, and it is worth more to us than a call-out fee.

Is a Partial Power Outage an Emergency?

Sometimes a partial power outage is an emergency and sometimes it is a five minute fix. The difference is easy to read.

For anything in the left column, our emergency line is answered 24 hours a day. The full picture of who to call at 2am, including the fire service and the utility, is on our emergency electrician in Hamilton page.

Half the House Dark: the Lost Leg

A partial power outage that takes exactly half the house has a specific cause. Ontario homes are fed by two 120 volt legs that combine to give 240 volts for the stove, the dryer and the air conditioner. Lose one leg and the result is exactly what people describe as a partial power outage: about half the circuits dead, the other half working normally.

The open connection can be in three places, and where it sits decides who pays.

• The utility side. A failed connection at the pole, the drop or the meter. Alectra repairs this and there is no charge to you.
• The service entrance. The mast, the cable into the house, or the main lugs in the panel. This is the homeowner's equipment and a licensed contractor's work.
• The panel itself. A failed main breaker or a burnt bus connection, which usually means a panel replacement rather than a repair.

An open neutral looks similar but behaves worse. Lights brighten in one part of the house as they dim in another, and 120 volt appliances start seeing voltages they were never designed for. That one damages electronics while you wait, so it is an overnight call rather than a morning one.

Who Fixes What

A partial power outage sits across three jurisdictions, and the meter is the boundary line between them.

Why This Happens So Often in Hamilton

Housing age explains most of the partial power outage calls we take. Pre-1950 homes in Durand, Corktown and the North End often still run 60 amp services and original knob and tube behind plaster, where every joint is a potential open connection. East Hamilton and Stoney Creek subdivisions from the 1960s and 70s carry aluminum branch wiring, and a loose aluminum termination at a receptacle is the textbook cause of a room going dark for no obvious reason. Mountain bungalows sit on 100 amp panels that keep gaining loads nobody planned for.

Weather does the rest. Ice loads pull on service masts, wind moves the drop where it lands at the house, and a flooded basement puts water near a panel that was mounted low fifty years ago. A partial power outage after a storm is very often a service entrance problem rather than a circuit problem.

More of what customers say is on our reviews page. Shops, warehouses and multi-unit buildings are handled through our commercial electrical services.

What We Do When We Arrive

Diagnosis before parts. A partial power outage has a cause, and replacing components until the lights come back is guesswork you pay for twice.

1. Test at the panel. Voltage on both legs, at the main and at the affected breakers. This separates a lost leg from a single faulted circuit in a few minutes.
2. Trace the circuit. From the panel to the first device, then along the run. Most faults are at a connection, not in the middle of a cable.
3. Check the usual suspects. Backstabbed receptacles, aluminum terminations, buried junction boxes and anything a previous owner added without a permit.
4. Explain the options. What can be repaired now, what needs a part or daylight, and what it costs either way, before further work.
5. Repair, then verify. The circuit is tested under load before we leave, not just switched on.
6. Notification and certificate where the work requires it. Notifiable work is filed with the Electrical Safety Authority by the contractor, before or within 48 hours of starting.

If the fault turns out to be on the utility side of the meter, you are told plainly and pointed at Alectra rather than charged for work that is not ours. If it turns out the panel itself has reached the end of its life, that becomes a scheduled panel and service upgrade rather than a repair, and the reasons are explained before anything is quoted.

Frequently Asked Questions

My power went out in part of my house in Hamilton, who do I call?

For a partial power outage, check whether your neighbours have power first. If they do, the fault is inside your home and you call an electrician: Apollo Electric at 905-921-5487, answered 24 hours a day. If the whole street is dark, call Alectra Utilities at 1-833-253-2872. If there is smoke or a burning smell, call 911 first.

Why is half my house without power but the rest is fine?

That version of a partial power outage almost always means one of the two 120 volt legs feeding the house has opened, at the utility connection, the service entrance or the main breaker. It is not a normal tripped breaker, and it should be looked at the same day.

Can I reset the breaker myself?

Yes, once. Push it firmly to off, then back to on. If it trips again immediately, stop and call an electrician. Repeated resetting on a faulted circuit is how a fault turns into a fire.

Why did a GFCI kill outlets in another room?

One GFCI protects everything wired downstream of it, which often spans several rooms. A tripped GFCI in a garage or a bathroom regularly takes out kitchen counter or outdoor outlets. Find it, press reset, and the outlets come back.

Is a partial power outage covered by the utility?

Only if the fault is on their side of the meter, such as the drop or the connection at the pole. Anything from the service entrance into the house is the homeowner's equipment and a licensed contractor's work.

How long does it take to fix?

A partial power outage from a tripped GFCI takes minutes. A single faulted circuit is usually the same visit once it is traced. A failed service entrance or panel takes longer because it needs a utility disconnect and an ESA inspection, so it is scheduled rather than done overnight.

References

• Alectra Utilities, reporting an outage, hazard or electrical emergency, staffed 24 hours a day.
• Alectra Utilities, what to do during an outage.
• Electrical Safety Authority, Ontario's electrical safety regulator.
• ESA, finding the right contractor, on licensing and the Authorized Contractor Program.