Space Heater Question
My daughter has a home built in 1920. Everything seems to work ok(lights, elect dryer,vacuum cleaners and other things), but the other day she plugged in a space heater in the spare bedroom and it kicked the circuit breaker. When she told me about it, I told her not to plug it in any more because it could be a fire hazard. ( I admit I don't know Jack about wiring or electrical stuff). But, what could have caused that? Is there something wrong with the wiring, or is the space heater too powerful? Could a smaller one work alright? I have never had a problem with space heaters, but I have heard that some people do.
Sounds to me like an overheated circuit; fairly easy to find in older homes as the types of loads common now weren't then - at all. We've got one in our house; part of the kitchen and den is on the same circuit as the bathroom, and having the TV, microwave and bathroom heater on at the same time will trip it... Rich
I have never seen a house wired with mostly 20 amp breakers. The standard breaker for most common circuits in a home is still 15 amps wired with 14/2 wire. A 20 amp breaker would require 12/2 wire, and is just not done, mainly due to cost and the fact that 15 amps runs just about everything, even in a modern house. The reason you don't find space heaters greater than 1500 watts is that is has already derated the 15 amp breaker by 80%. IE 120v x 15amps x 80% = 1440 watts. The heater rating is 1500 watts, but most likely it does not put out a full 1500. While it is true that you can wire a house with 20amp circuits, you will mainly find this on only one or two circuits, and even then it would be on a 240 volt line for in-line baseboard heaters. DO NOT arbitrarily replace 15amp circuits with 20 amp circuits thinking you can get extra wattage to work with. This is a recipe for a electrical house fire.
AUGHH Tony don't tell me that! I just rewired a 4,000 sf house with 12/2 which is a real bear to work with LOL . .. sheesh I told my sister we could use 14/2 - - - she only let me use 14/2 between the lights and the switches. But maybe that will help me with wiring my little shack . . . sure would be easier! Happy Thanksgiving everyone! Liz
IMHO I do believe there is something wrong with your math right here. Current is equal to watts divided by voltage in which case you would be running under 3 amps for 200 watts and that is on DC, AC runs at approximately .707 or 70% of the current draw of straight DC. To be on the safe side I have always rounded up to 1 amp per 100 watts and this allows for component aging an the like. In older homes it is a good idea when a breaker trips, to find out what else in the house is dead and this will give you an idea of what your expected load capacity might be. Dale