Coffeemaker My Bunn coffee maker drips prematurely as soon as water is poured in.

The Bunn coffee machine has an internal tank used for holding approx three potfulls of water at just below brewing temperature. When you add water for a potful, the thermostat senses cold water and starts the brew heater. The water level inside the tank comes up and goes through the sprayhead. This "surge" of water, that you call drips is normal. The hot water stratifies to the top of the tank, just like an electric water tank in a house. The internal pot heater kicks in and boils the water already in the tank, raising the water level in the siphon pipe to the sprayhead until the reservoir under the add water opening is empty.

THE WATER THAT IS POURED IN SITS IN THE TOP RESIVOIR, ONCE YOU CLOSE THE LID YOU RELEASE A TRIGGER WHICH IN TURN LETS THE WATER FLOW INTO THE MAIN RESIVOIR. THIS TRIGGER HAS A RUBBER STOPPER ATTACHED TO IT WHICH NEEDS TO BE CLEANED. MAKE SURE YOU CLEAN WHERE THE STOPPER SITS ALSO. THE TOP LID POPS OFF EASILY TO REVEAL THE INSIDE. TRIGGER WITH RUBBER STOPPER IS EASILY FOUND. HOPE THIS HELPS