Sheathed cable with ac/dc for airconditioning

[powerplay]

I had heard that some electricians run #14/3 loomex for 240 volt power for air conditioning from a condensor to the remote output fan which uses an DC signal for controls. I know we aren't supposed to run different voltages in the same raceway/cable, but I am curious how it would affect the performance with 240 in the red and black, then dc running through the whitre in the cable...haven't seen it, but heard that's how its done.

 

[kwired]

I had heard that some electricians run #14/3 loomex for 240 volt power for air conditioning from a condensor to the remote output fan which uses an DC signal for controls. I know we aren't supposed to run different voltages in the same raceway/cable, but I am curious how it would affect the performance with 240 in the red and black, then dc running through the whitre in the cable...haven't seen it, but heard that's how its done.

Different voltage is not the issue, different classification of circuit types is. If the control system is a class 1 system then it can run with the power conductors. It also can not be run using class 2 cable or terminate on a class 2 device such as a class 2 thermostat.

Some of the mini split systems I believe this is common, but they are not designed the same as other systems. I have little experience with them so I can't give you much detail on them.