Hydronic baseboards can be eliminated or repositioned, but realize that the number of feet of baseboard was probably sized to the BTU requirements of the room.

Easiest is if you have a basement. Normally the supply tubing is run in the basement along the perimeter of the foundation. Where heat is needed the horizontal copper tubing runs up into the room through the floor, is connected to the baseboard, and at the other end of the bb the tubing goes back down through the floor and into the basement to reconnect with the copper tubing down there.

The water that is circulated is hot...160-180 degrees...so be careful.

After turning the system off and allowing it to cool, there are not much material costs to eliminate a section of bb. Maybe $15-$25 for a new piece of copper tubing and a couple of copper couplings.

Labor? If access is easy, it shouldn't be significant.

So yes, you can eliminate a section of bb heat where the piano is. Or you could leave is in place and add a couple of valves below to have the water bypass that section of bb, that way if the piano ever went away, the heat could be restored with the opening and closing of a couple of valves.

The section of bb that is where the built-in cabinetry is to go can be taken off the wall and moved forward, perhaps in a toekick built into the base of the new cabinetry.

Draining a baseboard may allow air into your system, so it will have to be bled when you refill it.

Mongo

Thanks for the advice, Mongo. Very helpful and encouraging!