Cannot find bonding lug location on Raypak 156A heater

[rootusrootus]

The manual does not say too much other than the heater needs to be bonded, and they have a picture with an arrow pointing to where the lug should go. But there is nothing there! No hole, no indentation like there should have been a hole, nothing. Just perfectly smooth painted sheet metal like the rest of the heater enclosure. They included the copper lug, and a green screw (not self-tapping, either) to attach it to the heater. But I find no unused holes anywhere on the heater that look like they could be a candidate.

Anybody else run into this? Am I just being really dumb? I have a ticket open with Raypak but I have not heard back yet. Maybe if I can verify there is nothing behind the area where it should be according to the docs, I could carefully drill the hole myself and let the screw cut itself some suitable threads. Not ideal, but continuing without a bond is also not ideal.

 

[JamesW]

 

[rootusrootus]

Alright, I found it! You inspired me. That video clip is a 406A (I think), the layout is totally different from my 156A. But it got me wondering. The manual shows the lug on the right side, but the gas and power connections are on the left. That clip shoes the bonding on the same side as the gas/electric connections. So I opened up the front cover on mine (mostly to see if there was room behind the sheet metal to drill a bonding hole on the right side; there is) and low and behold there's a screw hole about an inch below the gas line. Really hard to see from outside since it's under the line.

So the manual is wrong, but there is a hole that seems usable. I do wish the green screw they included was a self-tapper, though. It's not a threaded hole.

 

[JamesW]

I do wish the green screw they included was a self-tapper, though. It's not a threaded hole.

Is there a nut for the screw?

 

[rootusrootus]

No, just the screw and the copper lug. The screw is a bit larger than the hole so it didn’t want to thread. I used a stainless self-tapping screw instead.

I’ll end up replacing that screw with a stainless bolt the right size, since self tappers are technically not code compliant.