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Sub Panel Sizing Question?

Hi; I am adding a small 8 x 20 ft room to my 4 bedroom 2 bath house. The new room will contain a Jacuzzi tub and a small (< 8000 BTU) wall mounted AC unit. This room will primarily be an exercise area. My main service includes an exterior mounted 150 amp main service disconnect panel which is equipped with breakers for the two pool pumps and one pool light. Inside the house, the main panel is a Cutler Hammer 30 position panel with 26 breakers installed. I would like to install a second new compact panel in the new room and connect it directly to the exterior mounted panel at the far end of the house. In this way the existing Cutler Hammer panel will be undisturbed and I will feel better having this additional new load center installed as opposed to maxing out the existing load center. This will also simplify wiring as only one set of conductors needs to feed the new room.

What size panel and what size main conductor would be required to support the loads of this small room which will also include the required number of outlets and lighting for 160 square feet? What will be the required size of the breaker added to the exterior service disconnect panel?

Thanks in advance!

Reply to
**THE-RFI-EMI-GUY**
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loads of this small room which will also include the required number of outlets and lighting for 160 square feet? What will be the required size of the breaker added to the exterior service disconnect panel?

You could do this with a 2 pole 30a disconnect type box with a 20a 2 pole breaker in it and you would be about 500% more than you need for

160 sq/ft (480va) and still have a dedicated circuit for your A/C unit.
Reply to
gfretwell

Just be sure to buy the suplimental ground bus and don't install the neutral bonding screw.

Reply to
gfretwell

the loads of this small room which will also include the required number of outlets and lighting for 160 square feet? What will be the required size of the breaker added to the exterior service disconnect panel?

With out knowing the loads for what your planning it would be impractical to try to guide you. You do not state if the tub requires electrical heating. The last spa I connected took 50 amps drew 40 amps ( measured ) all by itself ( electric heater ). Your equipment is it going to be electric?

Knowing the load will allow the wire to be sized according to the load to keep voltage drop with in standard limits.

What ever you do your grounding requirements for the spa and outlet spacing should be a primary concern. Your going to need a 4 wire circuit. Unless your spa and a/c are 120v. Most Spa's I have connected have a min of #8 ground wire to the service.

Best talk to some local pros and get guidance.

Reply to
SQLit

SQL is right, I missed the spa.

You might as well go for the 6-8 slot panel. It will give you plenty of room to breathe

Reply to
gfretwell

Reply to
**THE-RFI-EMI-GUY**

hi,

agreed with SQL but i need to add up some more. Joe, you need to know the total load connected required in your house first before asking to size a panel or else.

tks

magic

Reply to
magic

Reply to
**THE-RFI-EMI-GUY**

I could run around and total all the appliances plugged in at this instant , but that would be a variable I am sure is assumed in the electrical code.

Nothing fancy here, an electric range, electric water heater, airconditioning, electric washer and dryer, pool pump and pool light (the pool stuff is wired to the exterior panel). The main panel is a Cutler Hammer 30 position panel with 26 breakers filled. The house is

2200 square feet airc>hi,
Reply to
**THE-RFI-EMI-GUY**

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