Need to vent tube heat?

We're building a house and I'm planning on a custom cabinet for the main stereo, which will be in the living room. When playing, cabinet doors will be open to display components.

System includes ARC REF 3, CD-7, VS-115 (possibly replaced by REF 110 or 210), SME 20/2, and phono preamp to be determined. These put off considerable heat, which is an issue given that I live in Texas.

Do you recommend that I use a fan/vent system to pull heat out? Would it make enough of a difference, in terms of AC costs, to vent the heat? I suppose it might also help with tube life.

I appreciate any advice.