Howden-Ljungstrom Preheaters
Howden-Ljungstrom Preheaters Ltd., of 133, Helen Street, Govan, Glasgow (the same address as Howden Boiler and Armaments Co)
1920 Frederick Ljungstrom conceived the idea of the air preheater to reduce energy used in ventilation.
1922 The first Ljungstrom Preheater was installed
1923 James Howden and Co of Scotland-street, Glasgow after having made extensive trials at their works of the new Ljungstrom air preheater, acquired a licence for its application to all types of land boilers for England, and held, in addition the exclusive world licence for applying the preheater to marine boilers.[1].
1924 Name of Howden Boiler and Armaments Co was changed to Howden-Ljungstrom Preheaters (Land) Ltd[2]
Howden-Ljungstrom Preheaters were builder of heat exchangers on the Ljungstrom principle
1927 The Helen Street works were subsequently occupied by Fiat British Auxiliaries Ltd
1931 Company name changed to James Howden and Co (Land) Ltd[3]