f1100turbo, this is a water heater problem, not a furnace problem. There is no "sail switch" in a water heater.
As for the problem, if you have power at the receptacle, then you need to check for power at the electric thermostat, then to the element itself. Be careful when checking this as 110 volts will hurt you.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT