Diaphragm flow controller FCR series

massfor gas

Selas Flow Control Regulators (Product No. 5105) are double diaphragm spring balanced flow ratio control regulators. Selas Flow Control Regulators offer maximum control and fuel efficiency on gas-fired applications involving preheated air to the burners, or where burners fire against a varying back pressure. The FCR monitors air mass flow by means of a pressure differential across a POP Orifice Flow Meter (Bulletin 5720). The signal from the POP is applied across the regulator large top diaphragm; pressure differential automatically compensates for back pressure. Lower matching “gas” diaphragm is connected to suit the application. Three smaller diaphragms are used within the regulator to balance out dynamic and static forces in the control system. The FCR holds a constant air/fuel ratio from cold start-up through hot air application. All control components are on the cold side of the system and are unaffected by high combustion air temperatures, minimizing cost and maintenance and permitting initial start-up adjustment to be made on cold air at the high fire condition and adjusting gas to the desired ratio.