Cooling and using ice

Crushing ice

1. One may not crush ice on Shabbat, however one may walk on ice or snow.
2. One may melt ice on shabbat if the water which comes out goes to waste. Therefore ice can be disposed of in the sink, or one may cool a bottle with ice.
3. One may place ice into a cup of liquid but one shouldn’t accelerate the melting by pressing the ice. According to Sephardim one may shake the cup even if that accelerates the cup.
4. One shouldn’t put ice in a cup in order for the ice to melt and drink the water. If one did so, it’s advisable not to use the water but it’s not forbidden.
5. One may put ice into water to chill the water, but one may not place ice in a cup and intend to drink it when it melts.

Making ice on Shabbat

1. One shouldn’t make ice on Shabbat unless one feels that one can’t do without them on Shabbat.
2. One may put food into the freezer or refrigerator.

Defrosting food

1. One may remove food from the freezer in order to thaw in order to eat it on Shabbat but not if it won’t be ready until after Shabbat.

Ice Cream

1. It’s permissible to melt ice cream in order to eat it as long as one doesn’t put in a place of 113 degrees.
2. One shouldn’t make ice cream from powder on Shabbat unless it’s a thin mixture, one puts the ingredients in the reverse order than usual, and one stirs it differently.

Cooling a hot pot

1. A may not place hot (over 113 degree) solid food or a Kli Rishon in cold water. However, one may place a Kli Sheni into cold water.