Into service with raf
November 1st 2007 Wellman Robey is supplying nine Ygnette hot water boilers to a Royal Air Force base. The boilers are to replace and upgrade existing Wellman Robey Ygnette boilers installed in 1977. The hot water boilers consist of three 2500kW LPHW (4.5bar g) and six 800kW LPHW (10bar g) boilers, all fitted with dual fuel modulating burners supplied by Wellman's burner company, GP Burners. The Ygnette boiler is of a horizontal three pass wet back reverse flame design and has a large furnace. Combustion products are reversed in the furnace to pass through convection tubes forming the tube pass and then discharge into a rear outlet box provided with chimney connection. This can be arranged for either horizontal or vertical outlet. Modulating boiler controls improve boiler operation by monitoring water flow temperature to produce a continuous control signal that determines fuel input. Reductions in water temperatures lead to an increase in firing rate; this optimises efficiency and minimises emissions. Precise control of the air:fuel ratio helps minimise the level of excess combustion air and reduces heat losses in exhaust gases. More articles from Wellman Robey: | 
