[rf17830]

CL2 and CL3 are fire ratings. It means that the cable won't carry a flame into a wall cavity. It is an indication of a high quality cable. The manufacture spent money on UL testing and certification of the product.

The Honeywell Genesis, Belden and Monoprice speaker cables are widely used for AV installations. They are used in hot attics without any issue.

 

[ArgonautVans]

Running speaker wires in a “hot attic” has nothing to do with the heat generated (or fire risk) of running continuous current through (multiple) wires in a confined space. The heat is coming mostly from the current/wires themselves, not the environment.

Regardless, the wall cavities of a vehicle can certainly get hotter than and insulated attic.

If the wire insulation doesn’t have a temperature rating, I wouldn’t use it to carry power. How much money are you saving by not using the proper wire? Negligible…

 

[rf17830]

Here is a chart to calculate wire temperature rise.

Temperature Rise by Current | ISRayfast

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