The BTUs per hour to Heat a Room calculator computes the energy (heat) required to heat a space of a certain volume by a specified temperature variance..
INSTRUCTIONS: Choose units and enter the following:
BTUs per Hour (BpH): The calculator returns the energy rate in BTUs per hour. However, this can be automatically converted into other volume units (e.g. cubic yards or meters) via the pull-down menu.
BpH = L * W * H * ΔT * c
This formula is base on the simple formula mentioned in the Ferrell Gas article on.