Leaking from the tap - Sparge Water Heater 40L Once the tap is assembled... Test for leaks by filling the unit with enough water to cover the shank. If there are leaks, ensure that the silicone washer is flat and centered on the shank. Related articles What is a mash out? Do I need to do it? Instructions - 40 L Sparge Water Heater Why is my Sparge Water Heater Cutting Out? What do I do if my recirculation on my G30 is blocked? How does heating work in the Conical Fermenter?