The Fastest Wilesco! The D28 did not have a very long run and quite rare. Its boiler is larger than the D24s and the engine is raised on a small platform. The American version has a 1500W heating element, and when you build up pressure and open it fully, there is none faster. Considering the D32 has only 25% more (larger) boiler, yet 100% more engine (2), nine can compare to this great but rare Wilesco.