In one room I need to cut groove into a wall to accommodate a condensate drain from a minisplit air handler/evaporator in an adjacent room. I know I could use a pump but I rather rely on old fashion gravity to transport the condensate to a drain, but in order to do so pass through one room's interior wall on a downward slope. What would be the best way and/or tool do so ? Any advice on how to also protect the drain from getting pierced in the future from a nail/screw. Probably shouldn't worry too much about it but rather avoid it if it is worthwhile. For the tool, I was thinking of a 4" grinder.
Thanks in advance!