Any recomendations for low-voltage wires through walls?

Question

I have found a good central location to mount a router, however it does not have power nearby. Instead working with 120V wiring, I thought it might be easier to just make a small hole/tunnel/conduit out of PVC pipe and fish the small end of the power adapter through it. Distance wise, it's not far, just through a single wall, or about 4' - the problem is that this wall is between the house interior and the garage, and there is quite a temperature difference, so I would like to "fill it up" somehow such that there isn't much air moving in/out. Is there any good approach for doing this, while allowing the wire to be replaced? (for when the router dies in X years and it's time for a new one).

Thoughts:

1. some sort of "cap" that can be put on the PVC tube, such that only a small opening for the wire goes through it, something like two half-circles that fit together

2. Some sort of terminal where the wire connecting through the wall does not change, but cutting in a new wire would be easy, like this but longer:

Answer 1

The easiest is to get an extension cord for the low voltage cable on the AC adapter. Most likely the adapter comes equipped with a 2.1mm or 2.5mm center pin barrel type power plug. Extension cords for these are readily available. One would look like this:

The extension cable would allow you to power the router from within the same room from an electrical outlet instead of having to go off through the wall into the garage.

My favorite place to get various types of cables, including DC power extension cables, is PCH cables. Very reasonable prices. They have the 2.1mm size in 6 foot and 100 foot lengths.

You can also find such cables in eBay and at Amazon.

(Note: I am not affiliated with PCH Cables in any way other than being a very happy customer).