Dry Firing in Boilers

Dry Firing pic

Dry Firing
Image: preferred-mfg.com

As the president of Preferred Utilities Manufacturing Corporation, Redding, CT-based industrial equipment professional David Bohn led the fuel oil and boiler equipment manufacturer to a 380 percent increase in annual corporate revenue. In addition to his administrative accomplishments, David Bohn has expertise in multiple technical areas including the prevention of dry firing in boilers.

A big problem in the boiler industry, dry firing occurs when something interferes with the regular supply of boiler feedwater. If the boiler runs out of water, and safety features fail to engage, steam pressure will soon drop to zero. Although the true cause of this drop is a complete lack of boiling water (and, therefore, steam), the boiler will automatically attempt to make up for the lack of steam pressure by increasing internal temperature. Within minutes, high temperatures can irreparably damage the boiler due to a phenomenon called metal creep.

Boiler owners and/or operators can reduce the risk of dry firing by ensuring that advanced safety controls are set to trip the boiler offline when water supply is interrupted. They can also prevent dry firing by installing header-pressure transmitters on variable-speed-drive pumps, monitoring stack temperature closely, and performing regular automated low-water cutout tests.