My bunn coffee maker is just dripping when it is making coffee. Then the next time it makes it just fine.

Hello, I am wondering how long between times you are stating, as most Bunn commercial units, stay heating 24/7, and if water is not poured into the machine every couple of days, they will evaporate off water that is held in the tank. This drop in water level can cause short brewing, slow brewing, etc.. as the unit relies on a vacuum or suction to brew properly. You could also have a leaking tank gasket, or brew tube gasket, and it is seeping air into the tank, breaking the vacuum/siphon action, and then seals with water, or expansion at other times. Another cause would be scale build up, and pieces are floating in the tank blocking the flow of water, or your spray head may be clogging/clogged, which minor cleaning should take care of the sprayhead, and tube, or a major cleaning necessary for the tank.

Hope that helps, and thank you.