Replacing Internal Wiring in a Water Heater — Is It Supposed to Be Impossible?

[davismarks]

Hey all,

I recently ran into a frustrating issue while trying to repair my electric water heater (A.O. Smith ENT-50 110, about 7 years old). The black wire running between the upper and lower thermostats was burnt and needed to be replaced.

After disconnecting the wire, I discovered it was routed internally—somewhere inside the tank’s insulation. I tried everything: pulling, wiggling, probing with a coat hanger... but the wire wouldn't budge. It turns out the tank is packed with dense foam insulation, and the wire is basically embedded inside it. No conduit. No access. No mercy.

I did see this link which describes drilling a new hole from the top of the tank and a long drill bit so that new wiring could be routed through: http://waterheatertimer.org/How-to-rewire-electric-water-heater.html

But since I haven't seen anyone actually do that online and since the hot water heater is still under warranty, I'm just going to have the electric co-op replace the entire water heater.


So here’s my question to the pros and seasoned DIYers:


Is this standard across most modern water heaters? Are internal wires really designed to be “non-serviceable”? Or is there a better technique I missed?


And in cases like this, what’s considered an acceptable workaround: splicing in a jumper, or drilling a new hole from the top as described in the previous link?


Would love your advice for the future and to help others avoid the same mess.


Thanks,
Mark

 

[Fitter30]

All of them are foam insulation. There isn't enough good wire to solder on a new piece?

 

[Sponsor]

 

[John Gayewski]

You could run the wire externally with a wire channel.

 

[davismarks]

Hi, I did some more research and I think I have enough good wire there I could use a WAGO style connector that's rated for high temps and 10 AWG. I'm just surprised that all hot water heaters don't put their wiring into conduit to make it easier to replace the internal wiring. I'll also look into option of using an external wire channel. Would you drill a tiny hole into the access panel to fit the wire through? Edit: I guess it wouldn't be a tiny hole. I'd have to carve a small chunk out of the side of each access panel.

 

[Master Plumber Mark]

You could run the wire externally with a wire channel.

If one wire is burnt, odds are they are all "crispy" I normally just change the heater out....
you are better off doing that

I have changed thousands of elements and t stats over the years and have had to
add extensions to the wires due to dis-similar t stats .... it just took some wire nuts
and peices of same sized wire to do this... inside the electrical panels... no big deal

In your situation you could run the #10 coated wire on the outside of the tank if you so wish
but its not wise..... or your kids could mess with it and then you have a liability issue

Even if you change out the wire and also encase it in metal its gonna look like shit
and you will never be able to sell your home some day with it looking like this..

If this is rental property it is a no-go cause you will probably be liable and
It will certainly not pass inspection down the road..