Rewire of house for multiple subpanels?

[SarcasticDwarf]

Finally bought a house with a fantastic garage but the wiring leaves a lot to be desired.

Current configuration: 200amp main panel in house, 100amp subpanel in garage. All cables for the basement run through a full wall cavity. While the previous owner managed to get a cable from the main panel through the cavity to the garage, he could not fit another one for the a/c. As a result this pulls off the garage panel.

What would be the best way to fix this? Run a second large cable to the basement for its own subpanel (the other large cable is the one going from house to garage through basement)? This would allow me to eliminate all the other wires in the wall cavity but result in two subpanels.

The only other option I can think of is to run conduit between the attic and basement, but it seems like there are quite a few issues with this (cable fill, length limits, etc.)

The intent of this is to get the a/c off the garage panel and to fix the wiring that ranges from old (1950's) to sketchy.

 

[Bert_]

Why do you need to "fix" the wire for the A/C? I don't see any problem with the way it is now. Why do you think you need two sub panels, is the current panel full?

If you want to replace a bunch of wiring the easiest and cheapest way is to open up the walls, sheetrock is cheap.

 

[sberry]

I can understand wanting to move the A.C., may need to shed some load from there.

 

[SarcasticDwarf]

Why do you need to "fix" the wire for the A/C? I don't see any problem with the way it is now. Why do you think you need two sub panels, is the current panel full?

If you want to replace a bunch of wiring the easiest and cheapest way is to open up the walls, sheetrock is cheap.

Moving the a/c wire is a plus but not required (more of a perk). The wiring in the house needs to be replaced. For example, all general purpose outlets and all lighting in the basement is on a single circuit. To add another circuit I would need to open up the walls to be able to run it to the main panel. That might be Ok, but that chase is already overfilled.

 

[matt_i]

I don't see much of an issue with putting a new subpanel in the basement, and swapping the A/C breaker to the newest subpanel. Then you will also have room for more breakers in the basement area.

A quick assumptions: you have enough room in the Main for a new double pole breaker. Also going to guess a new homerun is going to have to be pulled for the A/C due to its cable length being insufficient to get from garage to basement, but maybe I'm wrong due to a different exterior penetration point.

 

[tailshaft56]

Any thoughts as 2 using a 2nd subpanel going to a genset transfer switch?

 

[wyliesdiesels]

Sounds like you need a rewire.

As asked above, is main full?

Put a subpanel in at opposite end of house and feed from there.

Is garage attached or detached? I assume attached.

Make and model of panels?

 

[SarcasticDwarf]

The main is not entirely full at the moment. There is a 100a feed on a breaker from the main to the detached garage. This routes through the basement (and also splits off for the water heater). My thought is to take that feed and put a subpanel on it. Ideally I can run a second feed from the main to the garage through the basement.

No idea on make and model, just that the main panel is less than a year old.

 

[wyliesdiesels]

The main is not entirely full at the moment. There is a 100a feed on a breaker from the main to the detached garage. This routes through the basement (and also splits off for the water heater). My thought is to take that feed and put a subpanel on it. Ideally I can run a second feed from the main to the garage through the basement.

No idea on make and model, just that the main panel is less than a year old.

The garage is detached so you cannot have more than one feed to it.

How many feeds run between the garage and the house?

If more than one branch feeder, youve got bigger problems.

 

[SarcasticDwarf]

A bit more info.

Two buildings:
House (main level and basement). 200a service. All electricity for the house is through the main panel except the house a/c.

Garage (detached): I believe there is one wire feeding to this through the basement. I would imagine there is a second line running back from the garage in the same trench or conduit to feed the house a/c. The wire from the main panel (60a breaker) is shown going into the junction box in the second pic.

From what I can tell there is one 60a feed for the electric water heater, detached (950sf) garage, and house a/c. All basement outlets and lights are on a 15a line.

 

[wyliesdiesels]

A bit more info.

Two buildings:
House (main level and basement). 200a service. All electricity for the house is through the main panel except the house a/c.

Garage (detached): I believe there is one wire feeding to this through the basement. I would imagine there is a second line running back from the garage in the same trench or conduit to feed the house a/c. The wire from the main panel (60a breaker) is shown going into the junction box in the second pic.

From what I can tell there is one 60a feed for the electric water heater, detached (950sf) garage, and house a/c. All basement outlets and lights are on a 15a line.

Can you expand on this?

Where is the water heater located?

Are you saying the water heater subpanel and AC are all fed from the same 60a breaker albeit in different locations- meaning the water heater and AC do not come from the subpanel?

If so you got major problems.

Can you post a pic of the nameplate on the water heater and AC compressor?

 

[Bert_]

I really hate to be that guy, but it might be worthwhile to get a pro to at least help you on this one. I don't mean any disrespect but it sounds like your in over your head.

At the very least make sure you get an understanding of what's going on now before you tear ANYTHING apart.

 

[SarcasticDwarf]

Oh, I plan to hire an electrician, but I first need to understand what I am hiring them to do. Much of the recent work was done by the only electrical contractor in the county and it seems to be the source of some of the problems.

Yes, that is one cable off a 60a breaker feeding the water heater and garage subpanel (which includes the a/c for the house).

 

[wyliesdiesels]

Oh brother. Its worse than you initially led on to believe.

Can you post a pic of the nameplate on the h2o heater?

And i would definitely get a different contractor!!

Thats a fricken mess.

 

[SarcasticDwarf]

Oh brother. Its worse than you initially led on to believe.

Can you post a pic of the nameplate on the h2o heater?

The more I dig into it the more that I see it is completely borked. That main cable running from the main panel to the large junction box in the basement? That is sized for at LEAST 350amps. Why? I have no idea, but the breaker sure as hell isn't.

Water heater is a Marathon MR50245, 4500 watt draw max (brand new).

 

[mike93lx]

Why do you think the wire is sized for 350 amps

 

[SarcasticDwarf]

Why do you think the wire is sized for 350 amps

THHW2, outside diameter of ~.93. Depending on the manufacturer that would seem to put it around 350-430. Almost all markings are on the back side of the cable, so all I could pull off was type.

 

[mike93lx]

THHW2, outside diameter of ~.93. Depending on the manufacturer that would seem to put it around 350-430. Almost all markings are on the back side of the cable, so all I could pull off was type.

Sounds like 500MCM. It's copper?

 

[SarcasticDwarf]

Sounds like 500MCM. It's copper?

Aluminum. Spoke with the electrician that most recently did the work today. Some total hack did most of the work and he came in and did just enough for the water heater to pass.

A few bonus pics of the main panel and the jb from hell.

 

[wyliesdiesels]

A yellow neutral?

*facepalm*

And yeah that JBox is 10lb of **** stuffed in a 5lb bag....

Looks like you have your work cut out for you.

 

[SarcasticDwarf]

Yeah, the wife is getting tired of hearing "are you f****** kidding me?!" from the other side of the house.

 

[Bert_]

A yellow neutral?

*facepalm*

And yeah that JBox is 10lb of **** stuffed in a 5lb bag....

Looks like you have your work cut out for you.

Dude, almost all AA8000 stabloy underground cable comes with a yellow neutral. It's used all across the country, I've probably buried miles of it, it's completely normal.

As far as the J-box, yeah it looks like kind of a cluster @#$% but I am going to refrain from passing judgement until we get the whole story.

Back to the OP, the stuff you are wanting to know is kind or hard to pick apart over the internet. Not that it can't be done but you need to take pictures and document every box, wire and splice before we will even understand what's going on.

If you are going to have an electrician do the work why not have him come out. You can tell him what you want to accomplish and he can explain some different options as well as any problems with the current set up or your new plan.

 

[wyliesdiesels]

Ive only seen yellow striped neutrals...

 

[Bert_]

Ive only seen yellow striped neutrals...

At least half of the underground I get has a solid yellow neutral. I think it is always the AA8000 triple rated URD. I've seen it in lots installs dating back to the early 70's also.
http://www.encorewire.com/wp-content/uploads/EncoreWire_ALCAT_TR_UD.pdf

I didn't mean any offence in my other comment, I guess the yellow neutral is not as common as I thought.

 

[wyliesdiesels]

At least half of the underground I get has a solid yellow neutral. I think it is always the AA8000 triple rated URD. I've seen it in lots installs dating back to the early 70's also.
http://www.encorewire.com/wp-content/uploads/EncoreWire_ALCAT_TR_UD.pdf

I didn't mean any offence in my other comment, I guess the yellow neutral is not as common as I thought.

No offense taken.

Im not a snowflake.

While Ive been in this biz for awhile, I know theres still lots out there I havent seen. Cali has stuff a lot different than other states.

We have mostly combination meter mains, very few divorced meter pans. SEU not allowed....

All the URD and other types of service entrance wire Pacific Gasp and Extortion or my local non profit PoCo uses has a yellow stripe or white stripe.

Ive seen (in pics) SEU used instead of rigid or emt mast in other states...not allowed out here...

 

[wyliesdiesels]

Yeah, the wife is getting tired of hearing "are you f****** kidding me?!" from the other side of the house.

i say that when Im pulling all the hack work out of customers panels...