Voltage controller for electric heating element for boiler

[brick]

I've read a bit on this forum about needing a proper voltage regulator for controlling an electric heating element for a boiler. I recently acquired an old but functional voltage controller. My question is whether such a controller would be appropriate for regulating an electric water heater element for my still boiler.
It is a Powerstat controller made by Aloe Scientific. Here are some pictures.

Please give me your opinion.
Thanks very much.

[sambedded]

it's a nice controller but not very powerful. you can use only 1000Watt Mac heating element at 120v

[rad14701]

While a nice variac, it doesn't provide enough power for our purposes... You need a minimum of 15A and a 240V variac would be better suited for larger elements...

[brick]

OK, thanks for the information. 1000W max output from that controller is probably not sufficient for a 13 gallon boiler.
Maybe would be OK to drive an electric element for a small boiler, say less than 5 gal?

[sambedded]

OK, thanks for the information. 1000W max output from that controller is probably not sufficient for a 13 gallon boiler.
Maybe would be OK to drive an electric element for a small boiler, say less than 5 gal?

It will work for 5gal boiler just not very fast. You can also install 2 elements. One running directly from mains and second through that variac.