By Alexandru Goncear, Owner and CEO, ElectON Enterprise. Washington electrical contractor license ELECTEL765MN.
The car is on order and you want the charger in the garage before it shows up. Fair enough. The question nobody answers for you at the dealership is whether your house can actually carry the thing.
I get this call several times a week, and about a quarter of the time the answer is not a simple yes. Not because anything is wrong with the house. It is because a lot of Federal Way went up between the mid 1960s and the mid 1980s, when a 100 amp service was generous, and nobody building off Dash Point Road in 1974 was planning for a car that draws 48 amps for six hours straight.
You can find out most of what you need to know yourself, standing in front of your own panel, before you pay anyone to come look. Here is the check I would run if it were my house.
What you are actually looking for
A Level 2 charger runs on 240 volts, the same as an electric range or a dryer, and it draws far more than either one for far longer. Most home units are rated somewhere between 32 and 48 amps of output. Because charging counts as a continuous load, the circuit has to be sized at 125 percent of that output. So a 40 amp charger wants a 50 amp circuit, and a 48 amp charger wants a 60 amp circuit.
That circuit has to come from somewhere. The whole question is whether your panel has both the physical room and the electrical headroom to give it up.
Step one: read the number on your main breaker
Open the panel door. At the top, usually, there is one breaker noticeably bigger than the rest, sometimes with its own little cover. The number stamped on its handle is your service size. In Federal Way homes it is almost always 100, 125, 150, or 200.
Write it down. Everything else depends on it.
If you cannot find a main breaker inside the panel, look for a separate box near your meter on the outside wall. Some houses here have the main disconnect out there instead. And if the panel has round glass fuses rather than breakers, you have a different and more urgent conversation ahead of you than the one about EV charging.
Step two: count what is already electric
Walk the house and note which of these run on electricity rather than gas:
- Furnace, heat pump, or baseboard heat
- Water heater
- Range or cooktop
- Clothes dryer
- Central air conditioning
- Hot tub, sauna, well pump, or shop equipment
Each one of those is a large load competing for the same service. A gas furnace and gas water heater buy you an enormous amount of room. All electric plus a heat pump plus an induction range on a 100 amp service, and you are close to the ceiling before the car arrives.
This is the single biggest predictor in my experience, and it is the one homeowners skip.
Step three: look for two empty slots side by side
A 240 volt circuit needs a two pole breaker, which occupies two adjacent full size slots in the panel. Not two slots anywhere. Two next to each other.
Count your empty spaces. Then look more carefully, because some of what looks empty is not usable. Tandem or twin breakers, the skinny ones that fit two circuits into one slot, mean your panel is already past its intended count in that spot. If every position is full, that does not automatically kill the project, since a subpanel or a change to the breaker layout can sometimes free up what we need. It does mean the estimate goes up.
Step four: read the brand name on the panel
Look at the label inside the door or on the front of the deadfront. You are looking for two names in particular: Federal Pacific Electric, often written FPE or branded Stab-Lok, and Zinsco, sometimes labeled Sylvania Zinsco.
If you find either one, stop the self-check here. Both brands have a long documented record of breakers that fail to trip when a circuit overloads, and both were installed all over this city during the 1970s. Nobody should be adding a 60 amp continuous load to one of them. The honest answer in that case is that you are looking at a panel replacement first and a charger second. I know that is not what you wanted to read. It is still cheaper than the alternative.
Step five: measure the distance
Tape measure from the panel to where the car will actually park. Follow the route the wire would take, around corners and along joists, not the straight line through the wall.
Under about 30 feet and inside the same garage, this part is cheap. Past 60 or 70 feet, or across the yard to a detached garage, and the conductor has to grow to keep voltage drop in check. Copper is priced by the pound. That distance is often the difference between two quotes people cannot otherwise explain.
So what does your answer mean
Rough guidance, and I want to be clear it is rough. If you have 200 amp service with gas heat and open slots in the panel, you are fine, and this is probably a one day job. With 200 amps and an all electric house it is usually still fine, though the calculation starts to matter more than the label on the breaker.
At 125 or 150 amps it truly depends on the rest of the house. I have put 48 amp chargers on 125 amp services without touching anything else, and I have had to talk customers down to 32 amps on that same size service because of what else was already drawing.
At 100 amps in an all electric house, expect to hear that something has to change. Either the service grows or the charger gets managed. And if the panel is a Federal Pacific or a Zinsco, the size is beside the point. Panel first.
Why my number can differ from your guess
What I run when I come out is a load calculation, and it does not work the way people assume. It is not a matter of adding up every breaker in the panel. The code method for an existing dwelling applies the square footage of the house, the nameplate ratings of the fixed appliances, and a set of demand factors that assume you are not running the dryer, the oven, and the heat pump simultaneously at full tilt. There is also a method that uses your actual recorded peak demand from the utility, which sometimes rescues a house that fails on paper.
The result is often more generous than homeowners expect. It is occasionally worse. Either way it is a number I can defend to an inspector, which the mental arithmetic in your driveway is not.
We run it before quoting, not after. Nobody should learn that their service needs replacing on the morning the truck is already unloaded in front of the house.
If the answer is no, you still have three ways forward
A service upgrade to 200 amps is the obvious one, and it is the right call if you are also thinking about a heat pump, a hot tub, or an ADU in the next few years. Do it once. Our itemized breakdown of what a panel upgrade actually costs walks through where the money goes on a job like that.
Load management is the option most people have never heard of. A load management device or a charger with built in load sharing watches the total draw of the house and throttles or pauses the car when everything else is running. It lets a modest service carry a charger it could not otherwise support, and it costs a fraction of a service upgrade. Not every situation suits it. When it fits, it is the best money in this whole category.
Turning the charger down also works better than people expect. A 32 amp unit on a dedicated 40 amp circuit still adds somewhere around 25 miles of range an hour. If you drive 40 miles a day and the car sits in the garage from six in the evening until seven in the morning, you will never once notice the difference between that and a 48 amp unit. People buy far more charger than their commute needs.
Permits, the utility, and money you can get back
Installing a Level 2 charger in Washington requires a permit and an inspection. That is not optional and it is not a formality. Unpermitted work on a circuit this size is the kind of thing that surfaces at resale, or worse, in an insurance claim after a fire. We pull the permit, schedule the inspection, and stay with the job until it passes.
Puget Sound Energy also wants to hear from you or your installer before a new charger goes in, so they can confirm the service feeding your house can support it. Their Customer Construction Services line is 1-888-321-7779.
While you are at it, PSE runs a rebate worth up to $300 on a qualifying Level 2 charger, and up to $600 plus as much as $2,000 toward installation for customers who meet the income thresholds. There are conditions attached. The charger has to be an ENERGY STAR smart Level 2 model on their prequalified list, it has to be Wi-Fi connected, you have to already own, lease, or have ordered the vehicle, and the application has to go in within 60 days of installation. The details and the current forms are on PSE’s EV home charger rebate page. Read the qualified product list before you buy the unit, not after. I have watched more than one customer miss the rebate by a few hundred dollars because they bought a charger they liked the look of at a big box store.
What happens when you call us
Somebody comes out and looks. That is the whole difference. I walk the panel, run the calculation, measure the run, and tell you what your options are including the ones that make us less money.
Then you get a written, itemized number. No trip charge, no dispatch fee, and the figure does not move unless the job changes.
We are based at 36007 9th Ct SW here in Federal Way, so the truck showing up in your driveway did not drive down from Seattle to get there. Most of the EV charger installations we do are within fifteen minutes of the shop, in Twin Lakes, Marine Hills, Redondo, and out toward Dash Point, plus Auburn, Des Moines, Kent, Milton, Edgewood, Normandy Park, SeaTac, and Burien.
Questions we get asked
How long does the install take?
A straightforward garage install on a panel with room is usually a single day, plus the inspection afterward. If the service has to be upgraded first, plan on coordinating a power outage with PSE and add a day.
Can I just use the cord that came with the car?
Yes, on a standard 120 volt outlet, and for some drivers that is enough. Level 1 charging adds roughly 3 to 5 miles of range an hour. If your daily driving is short and the car parks overnight, try it for a month before spending anything. If you drive 60 miles a day, you will run out of night.
Is a NEMA 14-50 outlet cheaper than a hardwired charger?
Slightly, sometimes. The outlet approach also gives you a receptacle you can plug other things into and a connection point that can loosen over time under sustained heavy load. For a unit you are going to use every night for a decade, I usually recommend hardwiring it.
Do I need a separate meter or a special rate?
No separate meter. PSE does have time of use options and pays attention to when you charge, so overnight charging is worth setting up in the charger’s app regardless.
We are getting a heat pump too. Which one first?
Tell us both at the estimate. If a service upgrade is coming either way, doing it once and sizing it for both is far cheaper than doing it twice. This is the most common expensive mistake I see.
What if the panel is already full?
Full is not the same as finished. Depending on the layout we can sometimes add a subpanel, or reorganize circuits to free two adjacent positions. It has to be looked at.
Get a real answer on your own house
Run the five steps. If you come out of it uncertain, that is normal, and it is what the free estimate is for.
Call (253) 508-7529 or request a written estimate and we will tell you what your panel can take. If you want to know more about how we work, our residential electrical services in Federal Way page covers the rest of what we do.
ElectON Enterprise 36007 9th Ct SW, Federal Way, WA 98023 (253) 508-7529 Washington electrical contractor license ELECTEL765MN