I'm trying to do a straight replacement of a single pole light switch from a regular rocker switch to a dimmer.
I pulled the old switch out of the box and found the following:
two wires coming out of the top, one red and one blue. I can't find anything online that tells me which of these wires is which so I'm not sure which one to attach as hot in the new switch.
there isn't a ground wire. I've read that the switch will be grounded just by attaching it to the metal box, but is this true? Should I attach a ground wire to the box?
I'm in Canada, if that helps. It's an older apartment too (which may explain the lack of ground wire?)