According to the rabbis:
* Unless an oven is heating, it cannot be opened on Shabat
But
* There apparently is no restriction on opening a refrigerator door even with the motor off.
The Torah tells us not to make a fire of the Shabat.
The rabbis tell us we are not allowed to increase or decrease an exiting fire on Shabat. That includes moving a fire - which is forbidden - to an area where it will be effected by the elements.
As with most things, there are exceptions to the rules. They are several; check with your sources for the exceptions.
To put a fence around the fence around the Torah law, the latter rabbis decided that if you turned on an oven before Shabat to keep food warm, in order to remove the food, the oven had to be heating when the door was opened.
Their reasoning was that when the door is open, heated air from the oven escapes and cooler air from the kitchen enters the oven, thereby causing the temperature to drop to a point where the oven's thermostat causes the oven to start heating. In other words, the action in the end causes the fire (heat) to be increased, and increasing/decreasing a fire is forbidden.
If the oven is electric powered, the heating element(s) must be glowing before the oven door is opened.
I once had a Shabat meal with a rabbi who was very particular about this issue.
Although I am not an engineer, I am a logical person.
I asked the rabbi if he waited until he heard the refrigerator motor come on before he allowed the refrigerator door to be opened.
Not necessary, he replied.
But, I countered, it's the same thing.
Open the refrigerator door and
* cold escapes from the unit while
* warm kitchen air enters into the unit
In the end causing the thermostat to cause the motor to come on to cool the insider of the refrigerator.
It's not the same thing the rabbi told me.
He, too, was not an engineer, but a basic understanding of air movement and heat transfer suggests that indeed it IS the same thing, the only difference is the temperature of the air in the exchange.
I am neither a rabbi nor an engineer, and I don't play either on tv.
If anyone can show me that it's OK to open a refrigerator on Shabat sans concern that the motor is/is not operating while the same does NOT apply to an oven, please let me know.
yohanon dot glenn at gmail dot com
