House hunting: what to look for w/r breaker box?

[brec]

I'm looking at houses to buy for me and my S85D. We've had a NEMA 14-50 in our current house, and we're happy with that so that's what I'm planning for the new one. I know that I should look at the distance between the breaker box and the garage, including whether any trenching would be required, to gauge the relative expense of installing the outlet. But what about the breaker box itself? Is there a way to see whether it has capacity for an additional 50A breaker?

Be gentle with me -- electrons are yellow, right?

 

[ColdRauv]

Depending on what size house you're looking at, look for a 200 amp service panel board from this century near your garage if possible, with at least 2 spaces next to each other.

 

[brec]

Depending on what size house you're looking at, look for a 200 amp service panel board from this century near your garage if possible, with at least 2 spaces next to each other.

Some of the ones I'll be looking at were constructed this century -- a couple are even new -- but some are up to 40 years old (1970s).

Edit: as to size: typical small-lot 3-4 BR, 1,800-2,500 sq.'

 

[Dwdnjck]

If you have a gas clothes dryer , look for an unused dryer plug for the simplest solution.

 

[BerTX]

Depending on what size house you're looking at, look for a 200 amp service panel board from this century near your garage if possible, with at least 2 spaces next to each other.

That is a good general indicator. If you don't know what "from this century" looks like, go to a big-box hardware store and mosey through the electrical aisle. Chances are, just the 200 amp criteria is sufficient, as houses with older systems often won't be that large. Usually there will be a main breaker in the box with the size on it.

Again, this is the physical capability of the system -- whether there is sufficient load capacity to add the breaker, you will not be able to know. Consult an electrician (or sometimes an inspector, if they are willing to give an opinion).

 

[ColdRauv]

Dont pass up the house that you (or your SO) loves based on its potential to allow charging, because electric services can be upgraded, and when they are upgraded, you can possibly split the service and get on a lower electric rate for your car charging.

 

[AB4EJ]

In most cases, 200 A is enough. It wasn't enough in our case, because there is also this 5-ton heat pump, huge spa, etc. (We had to upgrade to 400 A). To really know for sure on panel capacity you have to do a residential load calculation. Another thing you might be able to get (Alabama Power did this for me when my electrician requested it) is a historical study of power consumption (i.e., each month for the last year or two). These analyses can determine if existing panel is enough, Actually, my advice is - if it is even close, go ahead and upgrade - it increases the value of the home and ensures that you don't have to sweat if you add some additional large loads.

 

[Piney999]

Finding the right house is much harder then an electrician. Find the house and if you need a new CB panel, its $600. Small potatoes when house shopping.

 

[brec]

Dont pass up the house that you (or your SO) loves based on its potential to allow charging, because electric services can be upgraded, and when they are upgraded, you can possibly split the service and get on a lower electric rate for your car charging.

This house may be a second house in addition to my current one, and may be in use for only three years or so while I'm in a graduate program. I'm not yet sure whether I'll keep the current house. But, as of now, I don't want to spend a *lot* on upgrades.

Where I am now I have a TOU deal which provides cheap power from 10 PM to 6 AM.

 

[gregd]

On those older homes (30+ years), look up the brand of panel on the Internet for any safety concerns. We had a "Zensco" panel made by Sylvania in our 1983-era house, and our electrician noted that they tend to fail (as in, catch fire) over time. There are other brands with similar issues.

The panel was already full, so that kind of forced the issue, but to add a 14-50 plug in the garage he strongly recommended that we replace (and upgrade) the panel too, just because of the safety concern. Total came to about $2,100, most of which was the panel swap. In hindsight, the removed panel showed no evidence of impending failure, but I sleep a lot better at night. And the car is happy too.

 

[Blissedout]

When the electric cooktop was replaced by gas in an older house, the 50 amp circuit was able to be used for the charging circuit. Running the cable from the former cooktop location was a challenge but more doable than directly from the panel. You do not need to use the neutral, just the two lines and the ground for charging the Tesla, which is what the stove circuit had. (The neutral is used by mobile homes for 110 volt circuits. )

 

[alexvirital]

Doing an electrical heavy-up is spendy, especially if you're installing a charge port at the same time, but it's also absolutely worth. My house was built in 1952 and the previous owners were... amateur electricians. It was horrifying. The insulation around the main power in was cracked, allowing rainwater to run into and rust the breaker box... which they'd so badly forked up that it _didn't have a mains shutoff_.

We didn't get them to do much to the house before purchase, but I did insist on a heavy-up and new panel. Brand new box, completely redone breakers and space to grow came to about $2300. Absolutely, absolutely worth. It meant when it was time to add the 14-50 out back we didn't need to mess with the panel, and instead just run the cable, mount the outlet and be done.

In short: Finding the right house is the hard part. Then, finding a place _to_ charge. Lastly is the infrastructure, since that can be made to fit almost anywhere.

 

[Az_Rael]

The point about pools and spas is a good one. For the most part, if the panel is modern and the service is 200 Amps, I would think you would be good, but if the house has a pool or a spa or anything else big like that, the panel might well be full.

Maybe if its a two story with two AC units as well. I haven't ever owned one of those, but I know its a common setup for a two story home in some parts of the country. I would imagine that type setup would take up some panel capacity as well.

 

[tga]

You do not need to use the neutral, just the two lines and the ground for charging the Tesla, which is what the stove circuit had. (The neutral is used by mobile homes for 110 volt circuits.

You can't install a 14-50 without a neutral, even if your application doesn't use it. That's a code violation and, in some jurisdictions, illegal.

 

[DarkMatter]

Mention it to your inspector and they'll keep an eye out for issues. It shouldn't be a big deal if it has 100A service or bigger and a non-horrible brand of panel. If it does have a bad panel brand you'll want to replace it anyway so just use it as an item in negotiations. That is, assuming you live in a market that is not nutso. If you have to do things like bid with no inspection contingency just assume you might have to spend $10k on electrical upgrades, but also that won't be your biggest inspection worry.

 

[Rocky_H]

You can't install a 14-50 without a neutral, even if your application doesn't use it. That's a code violation and, in some jurisdictions, illegal.

This is correct, but perhaps could use a little more explanation. Yes, a 14-50 does need to have all of the wires to have a proper code-compliant installation. But if you need to do a long wiring run and are planning to use a wall connector instead of a 14-50 outlet, then the wall connector really doesn't require the neutral for code, so there would not be a reason to have to run that extra neutral wire all that way for nothing. That may have been what @Blissedout was referring to.

 

[tga]

This is correct, but perhaps could use a little more explanation. Yes, a 14-50 does need to have all of the wires to have a proper code-compliant installation. But if you need to do a long wiring run and are planning to use a wall connector instead of a 14-50 outlet, then the wall connector really doesn't require the neutral for code, so there would not be a reason to have to run that extra neutral wire all that way for nothing. That may have been what @Blissedout was referring to.

Agreed. This is also another reason that they really should bring back the 6-50 adapter. In most cases, you could probably extend/convert an old 10-50 3 wire range plug to a 6-50. If the original range outlet is home runned back to the main panel, the neutral wire should be connected to the combo neutral/ground buss bar. So repurposing it from a 10-50 neutral to a 6-50 ground is technically OK, although I'm not sure if the NEC allows a white wire to be remarked as ground.

6-XX - 240V grounded outlet (hot/hot/ground)
10-XX - 120V/240V ungrounded outlet (hot/hot/neutral) - old style 3 prong range/dryer outlet
14-XX - 120V/240V grounded outlet (hot/hot/neutral/ground) - new style 4 prong range/dryer outlet

 

[Dax279]

If you have a gas clothes dryer , look for an unused dryer plug for the simplest solution.

Don't forget though that a dryer plug is 14-30 o believe in most cases and Tesla has once again discontinued selling this adaptor

 

[suraj1194]

We had a very similar situation, with a temporary house move while wifey finishes medical school. I made it a point to check house panels at each place. Ours is an older house (40+ years) with a 150A breaker, with the run to the garage outlet being about 8-10ft . That was cheap to install a NEMA 14-50 for.

If the installation is a problem, then the best option is to check for the presence of a dryer plug, and use that for charging the car. However, those are 30A plugs and you'll have to dial down the max charging amps to 24A . With a NEMA 14-50, you can set it to 40A.

 

[Rocky_H]

Don't forget though that a dryer plug is 14-30 o believe in most cases and Tesla has once again discontinued selling this adaptor

I don't think that has really been discontinued. They had brought it back after a really long absence, but then it got caught in the recall they are doing right now of a few kinds of adapters, so they don't have any to sell right now while the recall takes higher priority.