Spirax Sarco stainless-steel control valves are at the heart of a money-saving system that enables boilers to run on tallow instead of fuel oil. Andy Gibson of A and L Gibson, an engineering company in Northern Ireland, has devised a manifold that enables this sticky alternative fuel to be used and says that one client in the meat-processing industry is saving around GBP 700 every week, while another is saving up to GBP 3000 in 24 hours, simply by substituting tallow when it is available. The change from fuel oil can be made at the flick of a switch. Each manifold is a drilled stainless-steel block. An immersion heater stops the tallow solidifying and a pump keeps it circulating at all times. Oil burner regulations require two valves to provide a double-safe shut-off to the burner. Gibson uses two Spirax Sarco piston-actuated PF61G valves, each of which is controlled in turn by a compact, electrically actuated Spirax Sarco control valve. The piston valves are stainless steel to withstand the corrosive tallow. They also have a high linear lift when open, which should prevent any solids getting stuck. “If I used quarter-turn ball valves, they would hold sticky stuff in the middle section”, says Gibson. “No solids get trapped in the Spirax Sarco valves. They also have a soft PTFE seat, so any particles that do adhere will release next time the valve opens”.