Many cars in the 1940s and 1950s were fitted with circular under-dash units – the most popular was the Smiths unit fitted to Morris, TR3, Austin-Healey,Jaguar XK and Land-Rover. The Smith's heat exchanger was made out of ‘tinned’ steel and would eventually rust away.
An alternative to Smiths, Clayton Classics units were used by Daimler, Alvis, Lea Francis, Armstrong Siddeley, Rover, and Jaguar saloons (and most bus cabs in the 1950s!). The Clayton Classics units were more expensive but used all-copper wire wound tubes for the heat exchanger, providing a very long service life, and resistance to blockage and leaks.
These heaters are still manufactured today from the original tooling, and are available with various water pipe configurations, with or without demisting in 6, 12 and 24 volts.
We also manufacture a special range of copper circular heat exchangers which replace/upgrade the Smiths heater exchanger. These come in a variety of sizes. Motors, fans,and backplates are also available. As long as you have a serviceable front plate with doors, a new heater can be built which is virtually indistinguishable from the original.