Buffer Tank Sizing Calculator (Testing / Experimental)

The large volume of water present in high mass style firetube boilers typically eliminates the need for a buffer tank. In certain unique applications, such as extremely small loops with very brief heat demand periods, a buffer tank may be used to increase system volume.

Input Parameter:

  • City: Select the nearest major city to the job location.
  • Warm Weather Shutdown: The temperature at which the heating plant is disabled for the summer.
  • Boiler Model: Select the boiler model for which you need to calculate the potential buffer tank size.
  • Number of Boilers: Provide the number of boilers in the system.
  • On/Off Hysteresis Range: The difference in temperature from when the boilers are enabled (on hysteresis) and when the boilers are disabled (off hysteresis) relative to the setpoint. E.g. a 20°F On/Off Hysteresis would indicate that the boiler plant gets enabled 10°F below setpoint and disabled 10°F above setpoint.
  • Total System Volume: Specify the number of gallon of water within the hydronic system (do not include boiler volume).

Assumption:

  • Temperatures and load profile based on ASHRAE climate data.
  • The maximum allowable boiler cycles is 12,000 per year.
°F
Δ°F
Gal