In order to properly size the wire per National Electric Code (NEC) standards you will need to know the amperage and the distance of the device (heater) from the source (circuit breaker panel). In order to know the amperage one would need to know the voltage since amperage changes inversely with voltage.
let's assume you have a 240 volt supply and that the furnace is a resistive load. In this case 20000 / 240 = 83.33 Amps. This would require 3 AWG copper wire.
Electric circuit need a main circuit breaker that can protect the whole circuit from short circuit even in ground fault. It's safer if you use breaker with built in ground protection.
Need to know what the wattage or the amperage is of the appliance. The load amperage is what governs the wire size and the breaker to protect the circuit.
I think you need to do some checking, A GAS water heater does not normally need electrical service that large- an ELECTRIC water heater will. So- just what do you have- gas or electric?
You need a 60 amp breaker.
No, an electric furnace does not need an outside air intake. For oil and gas furnaces an air supply is needed. It is called combustion air. It is needed for complete combustion of the fuel and not use the heated air that is in the house. Today's homes are built as a sealed unit to stop infiltration air from leaking in and costing the home owner more money to heat the home. Many installations use a motorized damper that cuts off the air supply when the furnace is not operating. This prevents a draft through the vent from the outside of the house when other extracting devices are operating.
If you put a 85 amp breaker in there it will overheat from the starting and stopping of the motor. The extra size of the breaker insures that the furnace will run without interruption and without overheating the breaker. And electric motor can draw three times the amperage rated on start up momentarily. This is why there is need of extra amperage ratings.
form_title= Electric Furnace form_header= Keep warm with an electric furnace. Do you need to replace an existing furnace?*= () Yes () No How old is your home?*= _ [50] What is the square footage of your home? *= _ [50] Will the furnace be the sole source of heating?*= () Yes () No
When the furnace in your home goes out, there are a few things that you need to look at before you get a new furnace. Get the furnace serviced by a professional electrician who will check the heating coils as well as the filter in the furnace. Check the circuit breakers in the furnace to ensure that they are working properly. If the breaker is not making contact, this could be all that you need to replace.
Need to know what type of furnace, electric, gas, or oil before question can be answered.
I'm not sure why your furnace would shut off after a power outage but first check your breaker in the breaker box to make sure it is in the on position. If this is not the problem remove the cover on furnace and look for a red reset button on the pump. Press this button and hold for a second or two and you furnace should restart. If however it shuts down again you have other problems and will need a furnace repairman.
if your heater just went out in your house and you need a really good electrical furnace you should really consider getting a whole new furnace from a hardware store or a heater store.
The circuit breaker is sized to the full load amps of the motor times 250%.
Electric circuit need a main circuit breaker that can protect the whole circuit from short circuit even in ground fault. It's safer if you use breaker with built in ground protection.
The equation for amperage is I = W/E, Amps = Watts/Volts. The amperage for the furnace would be, Amps = 15000/240 = 62.5 amps. So to answer the question, yes a 100 amp breaker with a #4 copper conductor will be sufficient to operate a 15 kW furnace. A 70 amp breaker will work but it is cutting the edge a bit too fine as you don't need the furnace to trip off during the winter months (northern hemisphere) if you are away from your home for an extended period of time.
I NEED WIRING DIAGRAM SHEMATIC GOODMAN Mod.PGC120225-3A
Need to know what the wattage or the amperage is of the appliance. The load amperage is what governs the wire size and the breaker to protect the circuit.
Usually 30 amp