ENPRO is supplying Stack Dampers for cycling operations to keep the HRSG hot during the short shut down operations . Stack Dampers are best used to decrease the total Hot and Warm Start up time when the shutdown time is not more than 12 hours.
The use of a Stack Damper is the most effective and inexpensive way to prevent cool air form flowing through the HRSG. 

The primary services and advantages of Stack Dampers are;

• Used for Cycling Operations,
• Prevents cool air from flowing through the HRSG,
• Decreases total HOT and Warm Start up time,
• Can be both manually or automatically operated from DCS with electrical actuator ,
• Tailor made design and manufacturing for each Plant,
• Installed at the outlet of HRSG stack.
• Designed for minimum pressure drop,
• Modular design for ease shipment and installation.