electrical

100A to 200A Panel Upgrade in an Older Arlington Home

Full breaker panel upgrade from 100 amps to 200 amps in an older Arlington home, including dedicated circuits for new appliances and a future EV charger, all permitted and inspected to current Virginia code.

Breaker panel upgrade from 100 to 200 amps in Arlington VA by Tim Whistler Plumbing

How we started

An Arlington homeowner called Tim Whistler Plumbing about an older 100 amp electrical panel that was finally running out of room. The original panel had served the home for decades, but a recent kitchen remodel, a new heat pump, and plans to add an EV charger in the garage were pushing the existing service past what it could safely handle. The breakers were tripping more often, and the homeowner had already had to defer the EV charger install because there was nowhere to put the new circuit. The fix was a full panel upgrade to 200 amps.

There were some challenges

Panel upgrades in older homes are rarely just a swap of one box for another. The existing 100 amp service entrance cable had to be evaluated to confirm it could handle the upgraded load, and in this case it needed to be replaced too. The meter base on the exterior was original to the home and also needed updating to current code. The grounding system, including the ground rod and the bonding to the water service, had to be brought up to current standards. And the upgrade required a permit from Arlington County, a coordinated power shut-off with the utility, and a final inspection before the new panel could be energized.

What we did

We pulled the permit, scheduled the utility cutoff, and ran a new service entrance cable from the meter to the new 200 amp main panel. The meter base was updated, the grounding system was upgraded and verified, and the new panel was mounted with room to grow. Every existing circuit was relocated into the new panel with appropriately sized breakers, with notes on what each one fed so the homeowner could actually read the directory. We added dedicated 240 volt circuits for the new heat pump and the planned EV charger, plus a few extra 20 amp slots for future use. Once everything was wired and labeled, the inspector came out, signed off, and the utility re-energized the service.

If your panel is original to a pre-1980 home, it's almost certainly undersized for how you actually use electricity today. The good news is that a panel upgrade is one of the highest-leverage electrical projects you can do, both for safety and for what you can add to the home down the road.

The outcome

The homeowner now has a 200 amp service with a clean, labeled panel, modern grounding, a code-compliant meter base, and dedicated circuits ready for the new heat pump and the EV charger. The nuisance breaker trips are gone, the electrical capacity for the home is roughly doubled, and there's room in the panel for additional circuits as needs change. The whole project was permitted and inspected by Arlington County, with no rework required.

Summing it up

Planning to add an EV charger, a heat pump, a hot tub, a generator, or a finished basement? Get your panel checked first. Tim Whistler Plumbing handles permitted electrical panel upgrades across Arlington, Alexandria, Falls Church, Bethesda, Silver Spring, Washington DC, and the rest of the DMV. Call 1-866-477-6190 to schedule a panel evaluation. Licensed electricians, code-compliant work, and 24/7 emergency electrical response.

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Details about this case

Date

September 14, 2025

Location

Arlington, VA

Timeline

2 days

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Common Questions You May Have

These are the most common questions people ask our professional plumbers and electricians.

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Do we install tank and tankless water heaters?

Yes. We install, replace, and service traditional tank water heaters and ENERGY STAR rated tankless gas systems for homes and businesses across Washington DC, Maryland, and Northern Virginia. We handle the gas, water, and venting work in-house since our team is licensed across plumbing, gas, and HVAC. Tankless conversions often qualify for utility rebates, and we'll walk you through which option makes sense for your home.

Do you install EV chargers and handle electrical panel upgrades?

Yes. Our licensed electricians install Level 2 EV chargers and handle full electrical panel upgrades (100A, 200A, and 400A) across the DMV. Older homes often need a panel upgrade to support modern loads like an EV charger, heat pump, or solar system. Every project is permitted, inspected, and brought to current code. Call 1-866-477-6190 for a panel evaluation.

Do you offer free estimates?

Yes. We provide free estimates for most installation and replacement projects, including water heaters, boilers, AC units, panel upgrades, gas line work, and full system installations. For diagnostic work on existing equipment (like an AC that isn't cooling), there may be a small service call fee that's credited toward the repair if you move forward. Call 1-866-477-6190 to schedule.

Do you offer 24/7 emergency plumbing, gas, HVAC, and electrical service?

Yes. Tim Whistler Plumbing offers true 24/7 emergency response for plumbing, gas, HVAC, and electrical issues across the DMV. Whether it's a burst pipe at 2 a.m., a suspected gas leak, a furnace that died on the coldest night of the year, or a panel that's tripping breakers, we have a licensed technician available. Call 1-866-477-6190.

What areas in the DMV do you serve?

Tim Whistler Plumbing serves homes and businesses across the Washington DC metro, including Montgomery County, Howard County, Frederick County, Arlington, Alexandria, Fairfax County, Bethesda, Tyson's Corner, Springfield, Falls Church, McLean, Kensington, Silver Spring, Chevy Chase, Takoma Park, and most surrounding communities in Maryland, Virginia, and Washington DC. If you're not sure if we cover your area, call 1-866-477-6190.

Do you serve Bethesda, Arlington, Silver Spring, and the rest of the DC metro?

Yes. Bethesda, Arlington, Silver Spring, and the wider DC metro are core service areas. We're regularly on jobs in Bethesda, Chevy Chase, Tyson's Corner, Falls Church, McLean, Kensington, Takoma Park, Old Town Alexandria, Northwest DC, and surrounding neighborhoods. Same-day service is often available depending on technician availability.

Are you fully licensed and insured?

Yes. Tim Whistler Plumbing is fully licensed and insured across DC, Maryland, and Virginia. Our active licenses include WSSC 6119360, Virginia 2710020030 and 2710059613, and DC PGM-1002028. We carry insurance for residential and commercial work, and we provide proof of insurance on request for any project that requires it.