DERATE

The owner or operator of indirect heating equipment who elects to achieve compliance with an applicable standard of performance by derating must: A. advise the commissioner in writing of the intent to achieve compliance by derating and the capacity level at which the owner or operator intends to operate this equipment; B. agree to a permit condition in the required operating permit that prohibits operating the equipment over the derate level; C. install a boiler steam flow meter to continuously record, indicate, and integrate boiler steam flow, and must: (1) submit a written report to the commissioner within ten days of any excess steam flow occurrence above the specified derate load; (2) use a one-hour averaging period in determining an excess above derate with corrections for deviations in steam pressure or temperature if required; (3) submit written yearly reports to the commissioner confirming that no excesses have occurred during normal operations; and (4) retain and make available for inspection by the commissioner or the commissioner's authorized employees or agents steam flow charts for a minimum of two years after the date of measurement; and D. submit an effective method of physical limitation of boiler load for approval by the commissioner before authorization of a boiler derate. The limitation may include a tieback signal from the steam flow meter to the combustion control system cutting back fuel input at the derate load, a maximum limit stop on the fuel input control drive or valve, or other equivalent physical means.