Main earth protective bonding conductors

[cliffed]

We now have no need to MEPBC to water if proved it’s not extraneous…is anyone MEPBC metal ducting for HVAC & such.

 

[pc1966]

Not something I normally have to do but if it were me...it depends.

If there is little chance of the duct being touchable along with anything else then I would leave it.

If it is likely to be touchable by anyone in contact with the building's CPC then I would IR test it and if less then 21k ohm then bond it just in case.