I was thinking about the sacrificial anode in my hot water heater. It screws in via a hole on the top of the unit.
Every time I've made a threaded plumbing connection, I wrap Teflon around the threads before screwing it in.
It occurred to me that Teflon is not conductive. So how does the anode bond to the case of the water heater?
Is it assumed that when tightening the Teflon will deform enough to let some metal touch?
Or does it use a parallel thread and seal on a gasket so as to not use teflon?
Or is it irrelevant and the anode works regardless of being bonded to the case and Earth ground?
Best Answer
The anode needs to have continuity to work, the Teflon or PFTE fills the voids to create the seal but the threads cut through and make contact. If you would like to verify this put some tape on screw it in and then remove, you will see small areas have cut through the tape and this is all that is needed.