DIY Home Improvement Forum banner
1 - 9 of 9 Posts

·
Registered
Joined
·
44 Posts
Discussion Starter · #1 ·
I live in Pennsylvania and have 100 amp service with a 20 circuit box.

The box is completely filled with breakers and a couple of breakers are doubled or even tripled up. (eg. two bedrooms connected to one circuit, etc)

However, I have gas heat for the entire house except for one recently finished room in the basement (which uses electric baseboard heat).

I've had electricians come to the house but I'm getting two different stories:

1) Some say they can install 30 circuit box and I can keep my 100 amp service which is completely big for me.

2) Others say you must upgrade to 200 amp service if I want a bigger box.

Does anybody know the truth behind either of these?
 

·
Registered
Joined
·
1,543 Posts
You should have a load calculation done to determine the amperage for your service. You can keep the 100 amp service size and just upgrade the SE and panel, or upgrade to 200.
 

·
Licensed Electrical Cont.
Joined
·
7,829 Posts
Yup, you can do either. If a load calc says you are well under the 100A service size then a larger panel is the way to go. Try finding a 30 space 100A panel though.
You could also install a sub-panel for probably less money that either of the other two choices.
 

·
UAW SKILLED TRADES
Joined
·
5,341 Posts
I live in Pennsylvania and have 100 amp service with a 20 circuit box.

The box is completely filled with breakers and a couple of breakers are doubled or even tripled up. (eg. two bedrooms connected to one circuit, etc)

However, I have gas heat for the entire house except for one recently finished room in the basement (which uses electric baseboard heat).

I've had electricians come to the house but I'm getting two different stories:

1) Some say they can install 30 circuit box and I can keep my 100 amp service which is completely big for me.

2) Others say you must upgrade to 200 amp service if I want a bigger box.

Does anybody know the truth behind either of these?
It generally isn't any big deal to have a beaker serving a couple bedrooms. It is less desirable to have a breaker (especially 15 amps) serving a couple bathrooms. If your meaning is that the breaker has two wires under its terminal then that can be an issue if the breaker isn't rated for two different circuits. In most cases you need to look at what loads the circuit serves in order to tell if you have overload issues. If your not tripping a breaker and not having to load manage I wouldn't worry about it.

There is nothing wrong with installing a panel with more circuits providing you know the diversity load of the home as mentioned by the others. A sub works also as Speedy mentioned. If your going to have electricians do the work I'd just opt for the 30 circuit panel. But you can install a sub yourself for 100 bucks or less.

As for the service it is common for utilities to only have a few choices. In my area the service to the home, if it has 100 amp existing service, must be upgraded to 200 amps. This doesn't mean you have to install a 200 amp panel....you can install any panel up to 200 amps and the appropriate main breaker. You will also have to upgrade your service entrance wiring to accomodate the new main breaker rating. You may also need a new meter base, mast, weather head and a few other things to be code compliant. So much more involved and more cost.
 

·
Registered
Joined
·
29 Posts
as stated, do a load-calc to make sure, but you're probably fine keeping 100A service if you've got everything on gas (furnace, dryer, range, etc.)

in keeping the same panel, one solution as mentioned was a subpanel, another would be swapping out some breakers for tandem breakers if they're fit in your panel. Speaking of, what kind of panel do you have?

here's a load calculation form too (excel spreadsheet)
http://www.pennelectric.com/loadcalc.xls
 

·
Banned
Joined
·
17,248 Posts
Do the Load Calc, figure out your needs now & in the future
Many people will buy a 200a panel as a sub & install it
Feeding it with 60a
Then when they are ready they upgrade their service to 200a & feed the 200a panel instead of the 100a
The 100a then becomes a sub
But that's a pain as you need to seperate the neutrals & grounds on the subs


Many people use a tandem breaker
2 breakers in the slot for one single breaker
These can't be used to supply 240v



 

·
Registered
Joined
·
44 Posts
Discussion Starter · #8 ·
Thanks for all of the great replies everybody!!

In case you're wondering, one of the electricians quoted me $1200 to just upgrade the box and service to 200 amp but noticed a bunch of code violations that he said the electrical inspector would definitely not allow and that he would fix them all for an additional $500. (mainly running electrical wires through floorboards instead of underneath them, fixing the junction boxes, etc, etc)

I'm still waiting to hear back from the other electrician and we have two more electricians coming over to give us estimates.

Anyways, it sounds like the 30 circuit might be a possibility if I get somebody to check the load on the house but there is only one problem. The very small baseboard heat in the attic is not connected so there is no way to turn that on and see what it's drawing along with everything else. We don't use the attic at all (except for storage) but if we have children in the next few years we might want to make that a bedroom.

Also, my dryer is 220v electric and not gas. (we bought it before moving into the house which is why it's not gas)

The water heater and furnace is gas though. (at least I'm 95% sure the water heater is gas)
 
1 - 9 of 9 Posts
Top