Final answer:
The minimum combustion and dilution air requirements for the boiler room containing a gas-fired hot water boiler and water heater can be calculated based on their input and output powers. For the given appliances, the air flow rate required for complete combustion is 400 ft³/h for the hot water boiler and 100 ft³/h for the water heater.
Step-by-step explanation:
The minimum combustion and dilution air requirements of the boiler room can be calculated based on the input and output power of the gas-fired hot water boiler and water heater. The input power of the hot water boiler is 200,000 Btu/h (58,620 W) and the output power is 160,000 Btu/h (46,896 W). The input power of the water heater is 40,000 Btu/h (11,724 W) and the output power is 30,000 Btu/h (8,793 W).
To determine the minimum combustion and dilution air requirements, we need to calculate the air-to-fuel ratio for each appliance. The air-to-fuel ratio is the amount of air required for complete combustion of a specific fuel. For natural gas, the air-to-fuel ratio is approximately 10:1.
Using the input and output powers of the hot water boiler, we can calculate the fuel consumption rate:
Fuel consumption rate = (input power - output power) / heating value of fuel
Assuming the heating value of natural gas is 1,000 Btu/ft³, the fuel consumption rate for the hot water boiler is:
Fuel consumption rate = (200,000 - 160,000) / 1,000 = 40 ft³/h
Similarly, for the water heater:
Fuel consumption rate = (40,000 - 30,000) / 1,000 = 10 ft³/h
Now, to calculate the required air flow rate, we need to multiply the fuel consumption rate by the air-to-fuel ratio:
Air flow rate for hot water boiler = fuel consumption rate * air-to-fuel ratio = 40 ft³/h * 10 = 400 ft³/h
Air flow rate for water heater = fuel consumption rate * air-to-fuel ratio = 10 ft³/h * 10 = 100 ft³/h
Therefore, the minimum combustion and dilution air requirements for the boiler room are 400 ft³/h for the hot water boiler and 100 ft³/h for the water heater.