I bought a 2 litre shabbat kettle that can be used during the week, but also on Shabbas when you change a setting. It says it is approved by the Zomet Institute for Halacha. Brand- Kennedy.
Is this kettle generally acceptable for use on shabbat?
Thank you for your question.
There is some controversy about certain aspects of the kettle, regarding a few issues. The main one is that the kettle has a heating element which gets red hot, and according to some poskim it would make the kettle muktza. However according to R’ Moshe Feinstein, R’ S. Z. Auerbach zt”l, and others it is not muktza and may be moved in order to use it. There is another issue, that when the water in the kettle finishes it causes the kettle to turn off, which can be an issue. The kettle from Ohr LeShabbat solves these issues therefore it is better, however this kettle may be used. You should however be careful to leave over water a few centimeters of water on the bottom of it so it won’t turn off.
Please see the attached gilyon, עומק הפשט 293 ויחי תשפ”א – קומקום מיוחד לשבת
which discusses the various issue involved, and the different opinions.