'What would cause an older 240 waterheater to increase my power bill. I
also have electric furnace that regularly gets a new filter each 6
weeks. AC/heater unit (outside) was serviced in late Dec, had both
sequencers replaced.'

ME: You could have a burned out element in either your water heater
and/or furnace since time of maintenance call, which would make them run
longer. Or, one of the new sequencers installed may not be turning on
one or more elements. Or, you could be cooking more . Most likely
however, there has been at least one electric rate increase since last
winter for your locale.