I have triedsearching for a timer circuit tooverrun my bathroom fan. I did have one of the small 4" fans with a timer circuit to start with but it wasn't upto the job. Had to upgrade to a 6" and although it was quite expensive by comparison it did not have a timer. I would like the timer function and have searched but have not found much info on adding a timer. Having looked at 2x old fansI have here with the small timer circuit boards there is really not much too them at all. Unless I just haven't them I cant imagine these cant be purchased from somewhere and wired into the fan supply line. Can anybody offer any advice? Wouldit be possible to utilise a second cheaper 4" fan with a timer make a relay circuit that would power both fans from the one timer circuit output?