Kashering MIcrowave and Dishwasher
I was wondering what the Rov shlit`a opnion is as to whether on could kasher
1. a microwave
2. a dishwasher
which was in possession of gentiles, and if yes, how?
Being that both of these do not receive non kosher taste absorption directly, they may be kashered. In a microwave, the food is generally covered during cooking. Even when cooked openly the steam is minimal during the average run of a minute or two. This steam is likely not hot by the time it reaches the walls of the microwave. In addition some microwaves have a fan which removes steam when generated. Therefore after not using the microwave for 24 hours and cleaning it out very well with a cleaning agent, it may be kashered. This is done by heating a bowl of water in the microwave for about 30 minutes. This will be a form of steam kashering based on the principle of כבולעו כך פולטו.
In a dishwasher a complete cycle will in fact generate much steam and heat which would seemingly cause absorption in to the walls of the dishwasher. However, dishes are generally placed in the dishwasher with only residual remnants of food, which is mixed with strong soap and detergent. This certainly spoils the food remnants and renders the absorption to non edible. Here too, after not using for 24 hours it should be cleaned out, this includes cleaning the gaskets, and all parts which may have an accumulation of food residue. Then it should be run on a cycle without dishes. This would also function as kashering through כבולעו כך פולטו, and permit it’s use.