Question

When using the standard method to determine the volume of indoor combustion air in space that has a furnace with an input rating of 125,000 Btu/h and 2 water heaters that have an input rating of 55,000 Btu/h for each water heater, the minimum required indoor volume of the room or space shall be

Answer 1

V = (Total Input Rating of Appliances) / (Btu/H per Cubic Foot)

In this case, the total input rating of the furnace and water heaters is 125,000 + 55,000 + 55,000 Btu/h.

Assuming a constant value for Btu/H per Cubic Foot, let's say 50 Btu/H per cubic foot:

V = (125,000 + 55,000 + 55,000) / 50

V = 235,000 / 50

V = 4700 cubic feet

Therefore, the correct minimum required indoor volume of the room or space should be 4700 cubic feet to ensure adequate combustion air for the specified appliances.