Old and New Water Heater Wiring
Our cottage was built in Michigan in 1970 and has an electric 240 v water heater. I don’t know how old the water heater is but we are in the process of replacing it. The existing wire going to the old water heater is 10-3 with no mention of a ground on the sheath. I have not had a chance to look inside the water heater junction or the service panel to see how a 10-3 wire was used.
In addition, connected to the top metal case of the old water heater is a large bare wire (estimated at 8 guage) that follows the inlet cold water pipe and terminates where the well input pipe goes into the ground – I assume this is a “ground”.
Questions:
How should the new 240 v 30 amp water heater be wired and grounded? It would seem that all is needed is a 10-2 w ground wire for 240 v/30 amps?
Does the ground wire from the water heater case to the well pipe provide any other purpose (it is only connected to the water heater) or can this be removed if the new water heater is grounded to the service panel?
My electrical reference says a water heater that is not in sight of the service panel needs a shut off by the water heater. Is this true and what type of “shut off” do I need to install?
Majorty of resdentail waterheater { tank type } useally are wired for 30 amp 240 volt circuit and typically use 10-2 NM or #10 THHN/THWN wires.
If some reason if have 10-3 NM just capped off white wire that will be not used in water heater useage due the waterheaters do not have netural connecton at all.
Yes if waterheater is not in sight a disconnection switch will have to be used in there.
{ A simple A/C disconnection switch will serve that purpose very easy. }
