Ask The Rabbi

Ask The Rabbi

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I have an electric stove for dairy foods and would like to use it for the Yomtov (festival) of Shavuot. Am I allowed to turn it on initially on low heat and then during Yomtov itself raise the temperature of the thermostat in order to warm up dairy food, just as it is permitted to turn the flame on a gas stove higher?

There are two sorts of thermostats in electric stoves:
One kind has three heat levels; Lo, Med, and Hi. There are two burners – one larger than the other, and when you set the heat on Lo, the small burner turns on. When you set the heat on Med, the small burner turns off and the larger one turns on. When you set the heat on Hi, both turn on. This means that when you raise the heat you are actually causing one burner to be turned off, and another one to be turned on from no heat at all, (not a matter of just raising the heat,) and this is not permitted. When you turn on Hi, you are causing the first burner to turn on from no heat also, and this is not permitted.
The second thermostat does not involve turning anything off, only increasing the heat, as in many kinds of ovens, where other circuits are not affected. This is permissible. It is worthwhile checking with an expert which kind of thermostat you have.

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