Water distiller variable resistor

[dernyarn]

I plan to get a 750 W, 220 V water distiller so that i can distill my own alcohol with it (in NZ so is fully legal), was thinking i should put a variable resistor on it so that i can regulate the temperature of the heating element so that i can seperate the methanol and ethanol more accurately. What type of variable resistor should i use for an appliance with these specs?

 

[spec]

SAFETY WARNING: dangerous voltages are involved in this thread so please observe the appropriate precautions and only consider any practical work if you are experienced with high voltages.

Hi dernyarn,

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Hmm, interesting project.

You could use a variable resistor to control the temperature of your distiller but the variable resistor would be expensive, bulky, and would get very hot. A variable resistor approach would not be very accurate either. So the variable resistor approach is not recommended.

The simplest approach would be to use a thermostatic switch which is placed physically in the distillate (water). The thermostatic switch would then be wired in series with the element in the distiller. Possibly, you could get an adjustable thermostatic switch; I haven't checked.

But a Rolls Royce, super-accurate temperature controller would be electronic, either off-the-shelf or home-built.

I would imagine that you could even buy a distiller with temperature control already built-in.

spec

 

[alec_t]

A heavy-duty 'lamp dimmer' would allow heating power variation, but as spec says, thermostatic control would be better.

 

[Les Jones]

I think a temperature controller such as **broken link removed** would be better and cheaper than a DIY solution. I bought one similar to this a few years ago and it use a proper PID algorithm to control the temperature.

Les.

 

[dernyarn]

Thanks for the replies. The thermostatic switch seems like a good idea but I'm not sure how well that'd work as the water distiller becomes air tight so I might have to drill a hole in the side for it then?

 

[spec]

Thanks for the replies. The thermostatic switch seems like a good idea but I'm not sure how well that'd work as the water distiller becomes air tight so I might have to drill a hole in the side for it then?

Yes, drilling a hole in the side is one way. It is not that hard to make the assembly water/air tight either.

But you must ensure that any surface exposed to the distillate is compatible and does not corrode or contaminate the distillate.

spec

 

[Ian Rogers]

Moved to High voltage forum....

 

[dernyarn]

I plan to use the pid temperature controller but instead of drilling a hole I found one person who puts it where the steam would go so I'll try that instead