took up one end of the locomotive, between the engine and drivers cabin; powered by fuel oil, it had the capacity to satisfactorily heat 10 coaches when the outside temperature was −10 °C. The equipment was sourced from Hagenuk, the full capacity being 670 L of fuel oil and 2850 L of water. Most of the locomotives were also equipped for push-pull operation, as well as for multiple working, controlled via a 36 pin control cable The safety devices Sicherheitsfahrschaltung (or Sifa) and Punktförmige Zugbeeinflussung (also known as PZB or Indusi) are fitted. Later on Zugbahnfunk; a cab to control room analogue radio system was installed. Other equipment includes sand boxes, a whistle and on some machines automatic door locking (when moving). Operations The first locomotives entered service on the Hamburg to Lübeck line, working push-pull double decked passenger trains, and replacing the BR 38.10 and BR 78 steam engines. The engines were also used on freight workings as well. On push-pull passenger working the locomotives were sometimes found in the middle of the train – which facilitated easier separation of carriages en route. Since the 1990s the Class 216 locomotives started to work more on freight than on passenger trains because of the lack of steam heated passenger stock. Between 2000 and 2004 the Deutsche Bahn fleet was phased out, with the last locomotive being decommissioned in 2004. However several locomotives were sold to private operators, where they are still in use. Variants In addition to the machines built in the 1970s, a few other variants have arisen subsequently, by rebuilding of existing machines. DBAG Class 226 The seven examples of the 226 Class were created by Deutsche Bahn for towing ICE 3 sets – for this purpose they were fitted with Scharfenberg couplers and the steam heating removed and repand replaced with ballast. They were replaced by converted DB Class 218s (subclass 218.8) in 2004 and scrapped in 2005. DH 1504 The first of the series of rebuilt Class 216s, DH 1504, was created in 1998 by the firm 'On Rail'. The concept was to create a new 'Class 216' medium power locomotive from retired state owned Class 216 locomotives; the result was an almost completely new locomotive, only the transmission, bogies and frame were saved from the original locomotive. The engine is a 1500 kW MTU engine, and the units are fitted for remote control operation. Overall,