Looking to add a 220v electric heater in 3 stall garage and currently have a 110v 60 sub panel in the garage. Any electricians, or electrical hobbyists, that know how hard it would be to add a 220v breaker and corresponding outlet?
220v from 60A sub panel in garage?
- Thread starter chicagocyfan
- Start date
It's easy. Buy a breaker, connect to the breaker box, run the correct wire, and install the receptacle needed. Done it a few times.
You want to add the breaker box out there? Much more difficult, pending where service enters the house.
Come again? I have a 200amp service panel in basement and a 60amp sub panel in garage. Are you saying I buy a 220v breaker and connect in the sub panel, run wire/receptacle?
I have a 200 amp breaker box in the basement. Ran a 220 line up to the garage, put a cheap thermostat in line with the cord, then I don't have to deal with the knob on the heater way above my head.
It's going to depend on the size of the electric heater, the existing load on your sub panel, the number of open spaces in your sub panel and the voltage( single or three phase) pulled to your subpanel. The load on your main panel should also be verified.
As long as you've run the correct gauge wire to your sub panel in the garage, then yes, it's as easy as that.
How many amps does the heater draw? You need to add up your loads on the current sub panel. Assume the heater is on full amps draw as well as lighting, etc. If you run out of amps (60), your main breaker on the sub panel will trip on amps.
I'd guess your electric heater to be 50amps. If that is the case, you will run out of amps really quickly. And, if you plug in a shop vac or a table saw, then expect a breaker trip. Typically, that kind of equipment needs a 20amp breaker (and appropriate wiring to support 20 amp service). If you have 50 wrapped up in heater and 20 on a separate circuit, you'll run out of amps.
If your electric heater is 40 amps, and you have space for a 220 breaker in the box (usually two spots are needed), then you might be OK.
There really isn't a one size fits all answer here. It really depends on a alot of things. Space in you sub panel, amps used already in your sub panel, your sub panel main breaker size.
Last, wiring matters too. Your limiter should, obviously, be your breaker. Wire gauge needs to support the max amps of the breaker so that the breaker trips before your wire starts to melt down.
With electrical, if in doubt, hire a pro.
I'd guess your electric heater to be 50amps. If that is the case, you will run out of amps really quickly. And, if you plug in a shop vac or a table saw, then expect a breaker trip. Typically, that kind of equipment needs a 20amp breaker (and appropriate wiring to support 20 amp service). If you have 50 wrapped up in heater and 20 on a separate circuit, you'll run out of amps.
If your electric heater is 40 amps, and you have space for a 220 breaker in the box (usually two spots are needed), then you might be OK.
There really isn't a one size fits all answer here. It really depends on a alot of things. Space in you sub panel, amps used already in your sub panel, your sub panel main breaker size.
Last, wiring matters too. Your limiter should, obviously, be your breaker. Wire gauge needs to support the max amps of the breaker so that the breaker trips before your wire starts to melt down.
With electrical, if in doubt, hire a pro.
If you truly only have 110v going to subpanel in the garage you will have to go back to the main. Hopefully the actual situation is that you have 220v at the subpanel but it is currently only populated with 110v breakers.
How to check? Assuming there is a breaker in the main panel for the garage subpanel, is it single pole (one space) or double pole (two spaces, with a bar connecting the switches)? If it's on a double pole breaker, it probably has 220v available even if it's not currently being utilized.
Another visual check would be to pull the cover off the garage subpanel, and see what wires are coming in. If there are 4 wires coming in (may be 3 insulated wires and bare ground) you likely have 220. Three wires--110 only.
With 220 you have two 110v hot legs (normally one red and one black) which are opposite phase. You connect across the two hots to get 220v, or using either on its own to neutral gives you 110v. The hot wire for 110 only is normally black. Either case will also have a white wire for neutral and should be a bare or green ground. If it's wired correctly, ground and neutral should be on separate bus bars inside the subpanel.
If you have a multimeter, you can also pretty easily measure voltage across two adjacent breakers in the subpanel to see if you show 220. Or measure across the incoming lines.
How to check? Assuming there is a breaker in the main panel for the garage subpanel, is it single pole (one space) or double pole (two spaces, with a bar connecting the switches)? If it's on a double pole breaker, it probably has 220v available even if it's not currently being utilized.
Another visual check would be to pull the cover off the garage subpanel, and see what wires are coming in. If there are 4 wires coming in (may be 3 insulated wires and bare ground) you likely have 220. Three wires--110 only.
With 220 you have two 110v hot legs (normally one red and one black) which are opposite phase. You connect across the two hots to get 220v, or using either on its own to neutral gives you 110v. The hot wire for 110 only is normally black. Either case will also have a white wire for neutral and should be a bare or green ground. If it's wired correctly, ground and neutral should be on separate bus bars inside the subpanel.
If you have a multimeter, you can also pretty easily measure voltage across two adjacent breakers in the subpanel to see if you show 220. Or measure across the incoming lines.
They are more expensive to buy and install up front, but natural gas garage/unit heaters are MUCH cheaper to run than electric. Depending on how much you run the heater, the ROI could be as short as a year or two.
