10 Signs You Need An Electrical Panel Upgrade
TL;DR: If your breakers trip a lot, lights dim, or your panel feels hot or buzzes—especially if you’re adding big loads like an EV or heat pump—you likely need an electrical panel upgrade. The checklist below covers the most common red flags.
Quick Checklist (10 Signs): Breakers trip often; lights flicker/dim; panel feels warm or smells “hot”; panel buzzes/hums; rust or moisture in the panel; double‑tapped/overcrowded breakers; old fuse box or panel 25–40+ years; out of breaker spaces; planning high‑draw additions (EV, heat pump, hot tub, induction); legacy wiring/gear causing inspection issues.
The 10 Signs (What To Look For + What To Do Next)
Upgrading a panel isn’t only about getting “more power.” It’s about safety, reliability, and providing headroom for today’s (and tomorrow’s) electrical loads. Not every symptom means a full service change, but patterns of the issues below signal it’s time to act.
Breakers Trip Frequently
Frequent trips usually indicate circuits running at or above safe capacity or intermittent faults. If multiple areas trip under normal use, you’ve likely outgrown your existing distribution and service capacity.
- What it means: Chronic overcurrent, insufficient capacity, or deteriorating components.
- What to do: Have a licensed contractor perform a load calculation and safety inspection; plan remediation and, if needed, a panel upgrade.
Lights Dim Or Flicker When Appliances Start
Dimming when large appliances kick on points to voltage drop and inrush currents straining an undersized system or loose terminations. Occasional flicker can be normal; consistent dimming is not.
- What it means: Capacity headroom is thin, or connections are compromised.
- What to do: Confirm tight, code‑compliant terminations and assess service size; consider upgrade to 200 amp service if loads are growing.
Panel Is Warm, Smells “Hot,” Or Shows Discolouration
Heat or discoloration is a warning. Oxidized or loose lugs and failing breakers create resistance and heat, which accelerates equipment wear and poses fire risk.
- What it means: Elevated temperatures from poor connections or overloads.
- What to do: Stop using affected circuits and book an immediate professional inspection; repair/replace components and determine if a panel replacement is prudent.
Buzzing Or Humming From The Panel
Panels aren’t meant to “sing.” Persistent buzzing can come from overloaded breakers or internal failures.
- What it means: Stress on hardware; potential breaker or bus issues.
- What to do: Have breakers and bus bars evaluated; plan component replacement and confirm whether a full upgrade is the safer long‑term fix.
Visible Rust, Corrosion, Or Moisture
Water and electricity don’t mix. Corrosion degrades contact surfaces, raising resistance and heat while undermining protective devices.
- What it means: Environmental damage and reliability risks.
- What to do: Address water ingress; replace the affected equipment—often the panel and, if needed, meter base/service gear.
Double‑Tapped Or Overcrowded Breakers
When multiple conductors are landed under terminals not rated for it, connections run hot and become unreliable. Overcrowding is a hallmark of DIY add‑ons and “temporary” fixes that stuck around.
- What it means: The panel lacks capacity or was expanded unsafely.
- What to do: Add breaker spaces with a subpanel or upgrade the main panel, depending on service headroom and your future plans.
Fuse Box Or Panel Older Than ~25–40 Years
Older equipment lacks modern protection (e.g., AFCI/GFCI) and may include obsolete or recalled components. Age also brings mechanical wear and insulation breakdown.
- What it means: Outdated gear, code gaps, and rising failure risk.
- What to do: Modernize to current Ontario Electrical Safety Code standards and ensure the panel/service meet today’s load profile.
You’re Out Of Spaces For New Circuits
If every slot is taken, expansion becomes a game of compromises. Tandem breakers are not a universal solution and may be prohibited depending on the panel.
- What it means: The system can’t grow with your home.
- What to do: Add a subpanel if service has spare capacity; otherwise plan a main electrical panel upgrade.
You’re Adding High‑Draw Loads (EV, Heat Pump, Hot Tub, Induction)
Electrification raises baseline demand and peak loads. Many Toronto homes moving beyond gas appliances or adding EV charging find 100A service tight.
- What it means: Future demand will exceed current service headroom.
- What to do: Get a formal load calc and evaluate 200A. For decision help, give us a call. ON Energy serves customers anywhere in the Greater Toronto Area.
Legacy Wiring/Service Gear Triggering Inspection Issues
Older aluminum or cloth wiring, non‑compliant terminations, or obsolete breaker models complicate maintenance and inspection approvals.
- What it means: System‑wide modernization may be the safest path.
- What to do: Plan a code‑compliant upgrade and inspection path with a Licensed Electrical Contractor.
Quick Reference Table
| Sign | Why It Matters | Next Step |
| Frequent Trips | Overloaded circuits/components | Load calc + pro inspection; plan upgrade |
| Dimming/Flicker | Voltage drop/capacity issues | Tighten connections; evaluate service size |
| Heat/Smell | Resistance and fire risk | Stop use; urgent inspection; replace/upgrade |
| Buzzing | Overloaded/failing breakers | Test/replace breakers; evaluate upgrade |
| Corrosion/Moisture | Damaged contacts; unreliability | Fix ingress; replace panel/gear |
| Double‑Tapped | Unsafe terminations | Add spaces or replace/upgrade panel |
| 25–40+ Years Old | Missing modern protection | Modernize to current OESC |
| No Spaces | Cannot expand safely | Subpanel or larger main panel |
| New High‑Draw Loads | Future overcapacity | Formal load calc; consider 200A |
| Legacy Wiring | Inspection/insurance challenges | Modernize wiring + service gear |
What’s Actually Causing These Symptoms?
These red flags are the “what.” Understanding the “why” helps you choose between a subpanel, a panel replacement, or a full service size increase.
Capacity Versus Demand Mismatch
Homes built for yesterday’s loads struggle with today’s appliances, electronics, and electrification. Even if you manage day‑to‑day, adding a heat pump or EV charger can push a 100A service beyond safe limits.
Aging Equipment And Heat
Time, oxidation, and thermal cycling loosen terminations and wear down breaker mechanisms. Heat rises with resistance, which further degrades parts—an accelerating cycle that shortens equipment life and compromises safety.
Code Compliance Gaps
Modern protections (AFCI/GFCI, proper bonding/grounding) prevent fires and shocks. If your panel predates these requirements, you’re missing critical layers of safety that come standard with today’s equipment.
Poor Distribution (Too Many Multi‑Purpose Circuits)
If too much is crammed on general‑purpose circuits, one appliance can cascade trips across rooms. Better distribution plus headroom within the panel eliminates nuisance trips and improves reliability.
Subpanel Or Full Upgrade — Which Is Right?
Choosing between a subpanel and a full upgrade comes down to whether you lack spaces or capacity (or both).
When A Subpanel Is Enough
If your main service has spare capacity but the panel has no free breaker spaces, a subpanel can neatly add room for new circuits. This is common during renovations where you’re adding lighting, a kitchen circuit, or a small workshop circuit without major new loads. You still benefit from updated breakers and clear labeling.
When Only A Full Service Upgrade Works
If a load calculation shows you’re near or above the service rating, or you’re planning high‑draw additions (EV charging, heat pumps, hot tubs), a full upgrade (often to 200A) is the right call. It provides headroom for electrification plans and eliminates recurring nuisance trips.
Permits, Utility Coordination & Inspections (Ontario/Toronto Specifics)
Electrical work in Ontario is regulated. That’s a good thing: it keeps people and property safe.
ESA Permits And The Ontario Electrical Safety Code (OESC)
In Ontario, panel and service work requires an ESA permit pulled by a Licensed Electrical Contractor (LEC). Your contractor handles inspection scheduling and ensures the installation meets the OESC.
Toronto Hydro Involvement
For service size increases or meter work, Toronto Hydro typically handles disconnect/reconnect and may review service entrance upgrades. Coordination affects scheduling, so plan timelines accordingly.
What To Do Next (Simple Steps)
Upgrades go smoothly when the steps are clear. Here’s the typical path:
- Stop risky symptoms (heat, burning smell, arcing/sparking).
- Book a licensed assessment to perform a load calculation and safety check.
- Decide subpanel vs. panel replacement vs. 200A service based on findings.
- LEC pulls ESA permit; Toronto Hydro coordination added if service size increases.
- Installation day: swap/upgrade, labeling, documentation.
- Inspection and sign‑off, and your system is ready for today’s loads.
FAQs
Yes. Your Licensed Electrical Contractor must pull an ESA permit and coordinate inspection. This ensures the work meets OESC requirements.
Often not. Electrification can push 100A services to their limits. Many homeowners plan ahead with 200A for reliable headroom.
A straightforward panel replacement is typically a single working day once scheduled. Service size increases that require utility coordination may take longer for disconnection/reconnection windows.
A subpanel adds breaker spaces but doesn’t increase the service capacity. A full upgrade modernizes equipment and increases available amperage when needed.
Yes—if you’re increasing service size or altering the meter/service entrance. Your LEC will coordinate.
It can be. Heat and noise often indicate loose connections or overloaded components. Stop using the affected circuits and schedule a licensed inspection promptly.
If the root cause is capacity or failing panel components, yes. An assessment will determine if the issue lies with the utility supply, branch wiring, or the panel itself.
Why Choose Electrician In Toronto For Your Upgrade
We’re ESA/ECRA‑licensed and handle permits, inspections, and Toronto Hydro coordination end‑to‑end. Our team performs formal load calculations to size your system correctly for EVs, heat pumps, and future electrification—no guesswork, no band‑aids.
You get code‑compliant workmanship to OESC standards, clean labeling, and clear documentation for your records. We stand behind our work with warranty and responsive aftercare.
Ready to stop the tripping, flicker, and capacity problems? Book a same‑day assessment for your electrical panel upgrade and get a plan that’s safe, compliant, and built for tomorrow.
