Name That Movie! (please help!)

I've been trying to figure out the title of a somewhat nightmare-inducing movie I remember from my childhood - ANY help would be greatly appreciated.

Details I remember:

• Probably made for TV
• Probably 1980s
• Mother and daughter live in a house or complex that has a garbage furnace in the boiler room / basement
• Daughter is always practicing a somewhat eerie song on the piano
• Daughter is a serial killer who (I think) disposes of the bodies via the furnace

Thanks in advance!

Moved to Movie Questions. In the future, please take a moment to place new threads in the correct forum.