Concealment of wiring in heater box

Hi Guys

I've tried to conceal wiring in the cabin where ever possible and cringing at the thought of having a sizable bundle of cables exiting the centre tunnel and rising adjacent to the heater box to the underside of the panel. While wrapping a split conduit will tidy this up to some degree, concealing it within the heater box and exiting just under the firewall recess would be far neater. This of course would obscure the vents somewhat and necessitate a duct or similar within the heater box itself.

Does anyone have any experience with this or perhaps point out any caveats.

Thanks in anticipation

I pondered that very same approach but rejected it. All things considered, I'm glad I did. When the plane is done and flying, that bundle of wire rising up the R side of the center cover is out of sight ... virtually completely hidden by the IP. You'll never see that wire bundle unless your doing the "human worm thing" laying under the panel for maintenance or annual work. And your passengers have w-a-y more things to look at outside the A/C than to notice a wire bundle behind their feet; they'll never see it either.

If you have already built the tunnel cover, you know that there is a shelf that forms the bottom of the heater box. Route the wires so that they exit just below the shelf and you will never notice them.

I had a very large bundle and had to cut away a large section of the left side of the cover below the shelf.

I split the wiring to go down one side of the heater box or the other, depending on where the wires needed to end up in the wings/tail/cabin. Some split conduit covers the wires from behind the panel to under the center tunnel. A couple of zip ties holds the conduit in place. I had to open up the left side where the brake lines on the 9A model enter the center tunnel. The other side is already opened up for the wiring conduit.

Left side:


Right side:


I made the heater control cable on the right side enter aft of the vertical angle so it clears the conduit, rather than penetrating the angle like in the plans.

Funny, that's what I've been working on all day. Unlike Bruce's I thought my 3 inches of slack would be enough, as it ends up after everything is bundled up its about 3 inches short. I couldn't find a decent wires stretcher so I modified the center tunnel (in progress). My clearance issue was where the wire bundle went over the facet fuel pump (carb) and the fuel line. I ended up making the center tunnel 2 pieces and making an angle.

Finally finished it, to me it's just OK. Now I need to recut my carpet to fit the angle.

Concealment of Wiring in Heater Box

Thanks for your thoughts guys

Once again the VAF resource has come through. I feel your pain with a miscalculation of wire length and believing there's enough slack in the run. Not quite requiring an alteration to the cover but next time I'll leave plenty extra cable and increase my options.