# Walker duct



## paul d. (Jul 13, 2008)

is ( are ) there any other devices being fed from said duct ? and how ???:blink:


----------



## Ima Hack (Aug 31, 2009)

paul d. said:


> is ( are ) there any other devices being fed from said duct ? and how ???:blink:


Yes, there are several receptacles in flush floor boxes. The new recepts will be under workstations so I can use a surface mount monument type box.


----------



## Bob Badger (Apr 19, 2009)

Ima Hack said:


> Yes, there are several receptacles in flush floor boxes. The new recepts will be under workstations so I can use a surface mount monument type box.


You want to find out the spacing of the cups on the duct, then measure from an existing used spot to the new spot. 

Assuming you can get some good measurements you should be able to break out the concrete above one of the cups which typically have a push in 2" metal seal that can be pried out leaving you with a 2" NPT threaded hole into the duct.


----------



## paul d. (Jul 13, 2008)

last walker duct i worked with had 2" threaded hubs on 12 " centers. RE'ed down to 3/4 and mounted box on a 6" nipple. let us know what you come up with.


----------



## Bob Badger (Apr 19, 2009)

This picture may help, if the duct was placed correctly the cups are only under the concrete by only 1/4" to an 1".


----------



## paul d. (Jul 13, 2008)

bob must have been there too. :thumbup:


----------



## drsparky (Nov 13, 2008)

If you know the pattern you can find the cups by tapping with a hammer, it will sound hollow. Then pound away.


----------



## Ima Hack (Aug 31, 2009)

Bob Badger said:


> This picture may help, if the duct was placed correctly the cups are only under the concrete by only 1/4" to an 1".


 A picture is worth a thousand words.

Thanks to all for the input.


----------



## Ed Kelley (Dec 5, 2012)

*Walker Duct Tooling*

An easy way to safety and efficiently install new electrical flush mounted boxes to concrete covered Walker Duct (underfloor duct) is to use a special device that drills concentric holes with a diamond bit for the concrete and an inner mounted carbide core bit for the smaller hole in the steel duct. A video showing the correct equipment can be seen on the Diamond Tool .net website or by calling them.

Ed Kelley


----------



## Wirenuting (Sep 12, 2010)

I forgot the spacing on walker duct. 
But I believe Walker went out of business in the early 80's?
Look in the access panel for the low voltage side, a model number should be there.

The picture bob posted is square D?? Never seen a 3 bank duct.


----------



## walkerj (May 13, 2007)

Wirenuting said:


> I forgot the spacing on walker duct.
> But I believe Walker went out of business in the early 80's?
> Look in the access panel for the low voltage side, a model number should be there.
> 
> The picture bob posted is square D?? Never seen a 3 bank duct.


They still make walker.


----------



## Wirenuting (Sep 12, 2010)

walkerj said:


> They still make walker.


I thought the Walker brand was sold off?
Thanks for the info. Now I can find more dog houses.


----------



## walkerj (May 13, 2007)

Wirenuting said:


> I thought the Walker brand was sold off?
> Thanks for the info. Now I can find more dog houses.


I think wiremold owns it because the label looks exactly the same.


----------



## Rollie73 (Sep 19, 2010)

I came across one of these things that was incorrectly installed this summer. The duct had no cups on top....and the knockouts were buried under 5" of concrete. We had to do exactly what the OP said, core drill the concrete then use a diamond hole saw for the steel plate. It was a scary situation, made me wonder if that duct was a homemade thing and snuck in before the inspector got a chance to see it


----------



## Wirenuting (Sep 12, 2010)

Rollie73 said:


> I came across one of these things that was incorrectly installed this summer. The duct had no cups on top....and the knockouts were buried under 5" of concrete. We had to do exactly what the OP said, core drill the concrete then use a diamond hole saw for the steel plate. It was a scary situation, made me wonder if that duct was a homemade thing and snuck in before the inspector got a chance to see it


When ever we had to fill them without the cups, we put some paper then a light layer if Pour-Rock.. You could find them by tapping on the tile floor. The pour-rock broke up easy and vacuumed out.


----------



## Rollie73 (Sep 19, 2010)

Wirenuting said:


> When ever we had to fill them without the cups, we put some paper then a light layer if Pour-Rock.. You could find them by tapping on the tile floor. The pour-rock broke up easy and vacuumed out.


 I wish the original installer had done something like that. It was my first time dealing with it and it wasn't a pleasent experience:no:


----------



## Wirenuting (Sep 12, 2010)

Rollie73 said:


> I wish the original installer had done something like that. It was my first time dealing with it and it wasn't a pleasent experience:no:


The original installer I would think did use the proper cups and marking screws. 
We didn't have access to them at the time of removal. 

I have used a cheap metal detector to find the screws below the floor tile. 
After the first one the rest are even distances apart and next to each other. 

Write down in the low voltage panel were the first cup is,,,, please


----------

