Electric Heater Question

[Luckyforward]

I am looking for a good electric heater for my elderly mother's enclosed front porch. At about 200 sq. feet, she is currently using a radiant heater that she points at her for warmth, but needs a heater with a fan to heat the room.

Here are the issues I am running into:

1. Her current heater is 1000 watts.

2. Heaters that I find that would do the job are 1500 watts, but it is my understanding that if anything else is on th same circuit with the heater, it will blow the breaker. There is only one circuit on the porch and the only other things on it are a TV and lamps.

Pardon my stupidity, but I am no electrician, so any guidance or opinions you have about how best to heat her porch would be greatly appreciated.

Thanks in advance!

[Guest bkelm18]

Most household circuits are going to be 20 amps and a 1500 watt heater is going to be drawing roughly 12-15 amps (give or take).

Is a ceiling fan out of the question? It would circulate the warmer air. Most 110v heaters I've had experience with really aren't that great. I'm sure someone here might have a better recommendation.

[Luckyforward]

Thank you for the suggestion; the ceiling won't support a ceiling fan. You do have a good suggestion though about the fan. There is a window AC unit that if used in fan mode could move the heated air around.

[laktrash]

I don't if something like this is large enough but I got my wife one for her office and she likes it . Her office has 2 outside brick walls and had heat but stayed very cold in the winter this worked well for circulating the heat all over. Its probably a 12x12 or better with high ceiling. She had been using a ceramic space heater.

Shop Vornado Panel Whole Room Heater at Lowes.com

I'm sure others with better knowledge will have some imput

[mikegideon]

She can probably run a TV and Lamp on the same circuit. 1500 watts is 12.5 amps. Adding a 60 watt bulb and a normal TV won't increase it that much. If it's a 15 amp circuit, it should work ok without tripping a breaker. If it's a 20 amp circuit, you will have plenty of headroom.

[tnhawk]

Better insulation, if possible, would help.

[Guest pfries]

If you have a volt meter measure the actual voltage at the outlet (it will not be exactly 120) and divide by the number of watts.

Example

115 volts at outlet

60 watt light bulb 60 Watts

19†color tv 70 watts

Heater 1500 watts

Table fan 10 to 25 depending on setting we will figure at 15

Total wattage 1645/115 =14.3 amps

If you have 110 volts at outlet it would be 14.95 amps and so forth.

A 20 amp breaker would be fine actualy suggested as you do not want to load a circuit beyond 85% .

however depending on the length of the run from the fuse box

if it was fairly short 12 awg wire would be fine

if it is getting long you would want to step up to 10 awg

[mikegideon]

If you have a volt meter measure the actual voltage at the outlet (it will not be exactly 120) and divide by the number of watts.

Example

115 volts at outlet

60 watt light bulb 60 Watts

19” color tv 70 watts

Heater 1500 watts

Table fan 10 to 25 depending on setting we will figure at 15

Total wattage 1645/115 =14.3 amps

If you have 110 volts at outlet it would be 14.95 amps and so forth.

A 20 amp breaker would be fine actualy suggested as you do not want to load a circuit beyond 85% .

however depending on the length of the run from the fuse box

if it was fairly short 12 awg wire would be fine

if it is getting long you would want to step up to 10 awg

Agreed there could be some voltage drop. That drop will also cause the heater to draw less current as well (E/R=I). Replacing the wire is the same effort as installing another circuit, maybe more.

[Guest pfries]

duplicate

Edited November 13, 2011 by pfries

[Guest pfries]

Agreed there could be some voltage drop. That drop will also cause the heater to draw less current as well (E/R=I). Replacing the wire is the same effort as installing another circuit, maybe more.

Depending on the age of the home if it is on a 15 amp breaker he could have14 awg or 12 awg. 14 is a bit light, being as it is on an enclosed front porch if it is over a basement it should not be that difficult to run a new line, if its on a slab it is up to the attic and that bites.

If the run was short 15’ to 20’ or less as a home owner i might slide with 14 awg and I would not worry about it. As a contractor you could not do it.

[mikegideon]

15A: #14

20A: #12

30A: #10

The breaker protects the wire. AFIK, it's not against code to use #14 wire on a 15A circuit. My house has that on the second floor, and it passed inspection. All the circuits downstairs are 20A, with #12 wire. Damifino why.

BTW: When I was wiring houses as a young whipper snapper, we used #12 for ALL wall circuits and lighting feeders. The only time we used #14 was for switch legs. Of course, there are a number of things done these days that we wouldn't do.

Edited November 13, 2011 by mikegideon

[Guest pfries]

Most definitely,

in MI which is where I was a contractor they have their own building and electric code. One of thirteen states that do, go figure, but I never kept 14awg on hand 12 was standard and 10 for dedicated appliance circuits.

But down here I have seen 14 used in some applications that I would not use it in. Some of it kind of scary in my book, but that’s why I said if it was a short run as a home owner for the 20amp I wouldn’t sweat it anything over 20’ or so I would make sure it was 12awg

[Guest bkelm18]

Anyway... Drop some money and put some 220v service on the porch and get a real heater.

[DaveTN]

If you are going to run a heater, have a dedicated line from the panel. Space heaters burn down a lot of houses without tripping the breaker.

[Guest packingheat]

You might consider replacing the window AC with a window heat pump.

[mikegideon]

Most definitely,

in MI which is where I was a contractor they have their own building and electric code. One of thirteen states that do, go figure, but I never kept 14awg on hand 12 was standard and 10 for dedicated appliance circuits.

But down here I have seen 14 used in some applications that I would not use it in. Some of it kind of scary in my book, but that’s why I said if it was a short run as a home owner for the 20amp I wouldn’t sweat it anything over 20’ or so I would make sure it was 12awg

Simply for insurance reasons, that ain't such a good idea. All the 14 wire in my house has a 15 amp breaker in front of it. AFIK, a 20 amp breaker in front of #14 wire would be considered a fire hazard.

[mikegideon]

If you are going to run a heater, have a dedicated line from the panel. Space heaters burn down a lot of houses without tripping the breaker.

The house wiring is fine IF it's done according to code. I'm betting that entire stat comes from bad cords on the heaters. Wear and tear will break the strands in the cords, and the result is heat. There is a point when the heat turns to fire.

Can't argue with a real wall heater. That is the safest, and will work better too.

[Guest pfries]

The reasons as a home owner that I wouldnt worry about it are that you can install a 20 amp or larger overcurrent protective device on a 14 AWG conductor under some of the specific conductor applications listed in 240.4(G) of the NEC.

As an example in a branch circuit feeding an air conditioner you

can use the minimum circuit ampacity listed on the nameplate to size the branch

circuit conductors and install an overcurrent device sized according to the

nameplate of the A/C to protect the branch circuit conductors.

Say I have an A/C with a minimum circuit ampacity of 18 amps and a maximum breaker size of

30 amps. I could use 14 AWG conductors for the branch circuit and install a 30

amp breaker to provide my short-circuit and groundfault protection for the

branch circuit.

14 AWG copper has a max overcurrent protection is 15 amperes.

But its allowable ampacity is 20 amperes at 60 deg. C.

Edited November 13, 2011 by pfries

[mikegideon]

The reasons as a home owner that I wouldnt worry about it are that you can install a 20 amp or larger overcurrent protective device on a 14 AWG conductor under some of the specific conductor applications listed in 240.4(G) of the NEC.

As an example in a branch circuit feeding an air conditioner you

can use the minimum circuit ampacity listed on the nameplate to size the branch

circuit conductors and install an overcurrent device sized according to the

nameplate of the A/C to protect the branch circuit conductors.

Say I have an A/C with a minimum circuit ampacity of 18 amps and a maximum breaker size of

30 amps. I could use 14 AWG conductors for the branch circuit and install a 30

amp breaker to provide my short-circuit and groundfault protection for the

branch circuit.

14 AWG copper has a max overcurrent protection is 15 amperes.

But its allowable ampacity is 20 amperes at 60 deg. C.

Hard wired? There is no way to exceed the capacity, no matter where the protection if it's hard wired. Voltage may drop, but the current is the same at all points in the circuit. That's the same deal as bussed power distribution to panels. The feeder wires to the panels are protected on the load side, but there's no way for your average Joe to tap in and exceed the current.

So, will code allow you to feed 14 ga wire with a 20 amp breaker? The spec on the wire doesn't matter. NEC has its own margins.

[Luckyforward]

As always, every time I ask a question on TGO, I get such helpful and useful feedback.

Thank you to all . . . I now have lots of options to consider!

[mikegideon]

It's kinda like guns. The best option usually isn't the cheapest one.

[Guest PapaB]

I like the oil-filled radiators like this one Shop De'Longhi Oil Filled Radiator at Lowes.com at Lowes. Nice even heat with 3 settings. Highest setting uses 12.5 amps.

[Guest shadow fox]

you could get an a/c heater combo for the window, they work fine at our camp and don't cost much to run

[Guest Lester Weevils]

To echo packingheat and shadow fox, if that present window AC unit is wired for 220 then it would support a toasty warm replacement window unit that has either cooling + resistive heat, or heat pump.

I've never had much satisfaction out of a 110 volt heater, but got good use out of 220 volt heaters. I have an old 25' X 25' concrete floor cinderblock wall shop building that isn't drafty and has decent enough insulation but gets pretty cold in the middle of the winter. Running a 110 volt heater doesn't even take the chill off the air on a cold day, but a 220 volt air+heat window unit or a 220 volt space heater makes the place reasonably comfortable.

Nowadays they make window air conditioners so shabby that they wear out and I have to replace em about every 5 years, and the last one I bought didn't have a heater in it. But I have had for about 20 years a nice floor-standing 220 volt "shop" resistive heater with a thermostat and slow-speed fan that works about the same as a resistive heater in a window unit. That heater 'mildly' circulates the air and the fan keeps the body of the heater from getting hot enough to be a fire hazard. You would probably have to set something flammable right in front touching the heater for a long time to have much chance of starting a fire.

edit: When I don't have a window unit with a heater, In the winter I just unplug the air conditioner and plug in the 220 volt shop heater into the air conditioner socket. There seems to be a flavor of the decade for the exact favored style of 220 volt plug, so sometimes you might have to change the socket on the wall or the plug on the device so everything matches. Just make sure of the current allowed on your 220 volt circuit etc. I think some of the different 220 volt plug designs are to imply different current requirements of the circuit, but it is an annoyance that there are so many incompatible designs of 220 volt plugs.

For keeping feet warm with a heater aimed right at the feet, those little 110 volt fan-driven ceramic cube heaters are pretty effective and safe as long as you remain vigilant. They are about 6" or 8" sheet metal cubes with a ceramic heating element, thermostat, sometimes a fan speed control, sometimes auto-fan-speed control, sucking air from the back and blowing it out the front. They can blow a good bit of hot air out the front without the chassis heating much and presenting a severe fire hazard. The ceramic heaters are good for spot-warming but they are useless for warming a large cold space.

Edited November 16, 2011 by Lester Weevils