My fan heater has only two settings, 1kW and 2kW. But what if I wanted it to consume only 200W per hour ? Could I find a device to put in between to supply less electricity, how would I do that?
closed as off-topic by laptop2d, Daniel Grillo, Autistic, Scott Seidman, brhans Oct 26 '16 at 20:59
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – laptop2d, Daniel Grillo, Autistic, Scott Seidman
As has been covered in the other answers, you have your units confused. If you want to reduce the heat output from your heater to an average of 200 W, you need to pulse-width modulate the standard 1000 W output setting. To do this, you need a time-switch. On for 20 minutes, off for 80 - repeat. Finding a time-switch that allows you to set enough on-off times at the right precision might be hard - a temperature based approach might be simpler.
This will not reduce the peak power draw, or how hot the heater might get (to a first approximation). Switching like this will increase the chance that the heater fails sooner, maybe not by very much.
There is an error in what you said: the fan heater power is either 1 kW or 2 kW, but when you say that you want it to consume only 200 W per hour you're talking about energy, which is just \$power \times time\$. Thus, your fan heater consumes either 1 kWh or 2 kWh, depending on the setting, (as pointed out by user FakeMoustache in the comments) and you would like it to have a 200 W power (thus reducing its energy consumption and the heat it gives you).
Then, anyway, the answer to your question is no, you can't put anything in between, if by "in between" you mean between the mains plug and your device. What you would have to do is to open your fan heater and modify its internal circuitry, those modifications depending on the fan heater you have.
Yes, you go to hardware store, electrical department, and buy a 1200W dimmer.
REWORK SUGGESTION: you will need to open up the AC cord, identify hot wire, and install (wire-up) the dimmer in accord with dimmer instructions. Then wrap the whole thing up by duct tape, in best DIY traditions. Do not use 2kW configuration.