DIY Home Improvement Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
This is an ongoing renovation. The electrician is doing his part in stages. He completed the first phase.

I wanted to add central air to the house. The original setup consisted of a main breaker shutoff next to the meter and a main lug only panel (no main breaker) on the inside. I decided to just have an exterior panel installed on the exterior. The condenser and air handler circuits would be run from the exterior panel.

The electrician used a feed through panel. He is feeding the interior house panel through those lugs. I don't think this is correct as the main breaker is rated at 200 amps and the interior panel is a 100 or 125 amp with no breaker.

What would have been the proper way to do this? I thought he was going to install a 100 amp breaker in the exterior panel and feed the old panel from that.
 

·
Deleted Member
Joined
·
837 Posts
Yes, there is a permit for the ac and electrical. I would like to get it right the first time and not fail the inspection. I would also like to know for personal knowledge.
Personally, I wouldn't worry about it one bit.
It's not YOU failing inspection, it's your electrical contractor. And he is the one that has to deal with it.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #7 · (Edited)
Was the house panel fed from the same 200 amp outside breaker before?

It was fed by a 125 amp disconnect/shutoff next to the meter. The disconnect was removed and a 200 amp panel was installed in its place. If I'm correct, the panel inside will not be considered a subpanel which will likely open up more issues. I believe all the neutrals and grounds would have to be separated. The panel just has a single neutral/ground bare aluminum wire fed to it.
 

·
Registered
Joined
·
3,257 Posts
It was fed by a 125 amp disconnect/shutoff next to the meter. The disconnect was removed and a 200 amp panel was installed in its place. If I'm correct, the panel inside will not be considered a subpanel which will likely open up more issues. I believe all the neutrals and grounds would have to be separated. The panel just has a single neutral/ground bare aluminum wire fed to it.
I suspect you typed NOW and the spell checker heard NOT. And yes, your house panel will now become a sub-panel and the bond jumper should be removed and if any neutrals and grounds are commingled on the terminal bars, that will have to be sorted out.

Check the amperage rating of your house panel... it should be rated as 200 amps if it is to be fed directly from the 200 disconnect. The only way around that would be to invoke the NEC tap rule, in which case the taps would have to land on protection based on whatever size they are. Taps have to be in conduit all the way.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #9 ·
I suspect you typed NOW and the spell checker heard NOT. And yes, your house panel will now become a sub-panel and the bond jumper should be removed and if any neutrals and grounds are commingled on the terminal bars, that will have to be sorted out.

Check the amperage rating of your house panel... it should be rated as 200 amps if it is to be fed directly from the 200 disconnect. The only way around that would be to invoke the NEC tap rule, in which case the taps would have to land on protection based on whatever size they are. Taps have to be in conduit all the way.
Yes, I meant to write "now."

It is an old Murray panel. I believe it is rated at 125 amps. The electrician gave me two options when he was bidding the job. The other option was to replace the interior panel. I didn't go this route due to running wires and I thought the service wires might be too small. I'm not sure what gauge they are, but the aluminum wire (with insulation) measures about .45 inches.

What are my options now? Can a 100 amp breaker just be added to the exterior panel that would feed the interior panel?
 

·
Super Moderator
Joined
·
23,932 Posts
If the panel was fed by a disconnect at the meter before it is STILL considered a sub panel as it was a sub panel before and should have a four wire feed.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #12 ·
The home was built in the 70's. From what I've read, a main breaker at the meter with a main lug only panel is common for apartment complexes. This is a duplex, so I'm thinking that is why they set it up this way.

I attached a pdf of how it is wired now.

The issue is that the main lug only panel is rated below the main panel. That is why I'm thinking it needs to be protected by a breaker. I've read that the NEC allows for a backfed breaker with clip in a main lug only panel to convert it into a main breaker panel. The wire going from the feed through lugs to the interior panel would still not be protected. I've noticed on other houses that the service wires go directly from the meter to the interior main breaker panel.

It would take a lot of remodel work to run a 4 wire feed through the structure.

 

Attachments

·
Registered
Joined
·
9 Posts
Discussion Starter · #13 ·
I'm meeting with the electrician Tuesday or Wednesday. I'm not real confident that the inspector will catch everything. It is a small city and I doubt they have an inspector for each individual trade.

I plan on mentioning adding the 100 amp breaker to the exterior panel. What about the use of a 3 wire feed. It has been that way for 50 years, although the grounds and neutrals are not separated in the panel. I remember him mentioning adding two ground rods 6 feet apart at the service entrance panel.
 

·
Registered
Joined
·
3,257 Posts
To be code legal and safe, you will need a system ground conductor in the indoor panel. I suspect your electrician will attend to that. It was not actually up to code before but that doesn't count for anything now. You should see that it gets fixed in the process.
 

·
Registered
Joined
·
922 Posts
...I'm not real confident that the inspector will catch everything. It is a small city and I doubt they have an inspector for each individual trade...

In a city I did electrical work in the code enforcement officer actually did not do the electrical inspections. I had to bring in a third party state certified inspector have him inspect my work and then sign off on the permit as "Passed". Then the code enforcement officer took a picture of the signed off permit and put it in his records. The inspector also sent in a card showing it passed.
 

·
Registered
Joined
·
3,257 Posts
In a city I did electrical work in the code enforcement officer actually did not do the electrical inspections. I had to bring in a third party state certified inspector have him inspect my work and then sign off on the permit as "Passed".
I found that to be true in several places, mostly smaller cities that couldn't afford a full time inspector for each trade but still wanted good risk management against dangerous conditions.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #17 · (Edited)
To be code legal and safe, you will need a system ground conductor in the indoor panel. I suspect your electrician will attend to that. It was not actually up to code before but that doesn't count for anything now. You should see that it gets fixed in the process.
From what I read, they just changed the code around 2008. It was for detached buildings, however. I'm not sure if they will grandfather the old electrical panel in or not.

It wouldn't be that difficult to run a ground wire to the exterior from the inside panel and run a ground rod for that. I'm not sure if that is legal, however. The neutral will then be the bare aluminum wire.

There are plenty of instances where 3 wires were run. They also used to run them to dryers and stoves. If I didn't decide to add the AC. It would likely have the same 3 wire electrical setup for the next 20 years. I doubt anyone has upgraded their electrical to that extent on this street.

I don't think adding the ac and exterior panel made it more unsafe that it has been for the last 50 years.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #19 · (Edited)
So, the electrician is going to have to run two 30 amp circuits around the exterior of the house anyways. One for the condeser and one for the air handler. I was thinking he could run conduit for the service feed for the interior panel (4 wire). It would probably be pretty ugly if it was just strapped the side of the house. If it was buried, it would have to pop up and enter through the utility room, run along the wall, and then pop back into the drywall to feed the meter.

What are the options for burying the service feed cables? Does it still only need to be buried 18 inches? I'm guessing PVC would be used. What size would it be 2 inch?
 
1 - 19 of 19 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top