-25 Degree C Conductors needed

[Loffgren]

So we are doing some lighting work in a freezer -25 C, the fixture wires are THWN and are becoming brittle and shorting out. Eight of the 20 fixtures. I am looking at table 310.13 and dont see any specs for low temp wiring..Any advice would help...

I thought of heat shrink over the conductors, or XF, XLPE???

 

[MarkyMarkNC]

I would think XHHW would work. I believe the jacket on XHHW is polyethylene, rather than the PVC used on THHN. Polyethylene has a much lower temperature rating than PVC generally.

Looking at the Southwire website, I don't see a lower end temperature rating on the XHHW, but you could probably call them and get an answer on it.

Smaller gauge XHHW would have to be special order, I'm sure, but they usually have at least black / white / green colors in stock at the factory.

 

[drbond24]

Service Wire has this XHHW-2 (top of the linked page) that is rated down to -40 degrees C.

 

[Loffgren]

Nice thanks for the help!