Electromagnetic valves are available from many suppliers, but I'd like to mention that a German magazine rana project of a house heating control that used normal bimetal controlled radiator taps in the rooms. The controller controlled them through a couple of power resistors which heated the valve only (and fooled the bimetal inside). Peter -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body