This dual purpose boiler from an unknown manufacturer was only offered by the firm for a relatively short period during the mid-1920s. Their 1925 heating and ventilation catalogue describes the boiler as follows:
This Dual Purpose Boiler will Provide Hot Water for Domestic Purposes and heat Radiators at the same time, and it should be connected up to a storage cylinder in the usual way. The two waters do not mix, and the Domestic – Water cannot become discoloured by the Boiler, being contained in a battery of Copper Tubes (with copper lined Headers) heated by the water in the body of the Boiler.
The Boiler can also be used with advantage for Domestic Hot Water Supply only.
In districts where the water is very hard or very soft the distinct advantages of this Boiler become apparent, as the deposit or incrustation can easily be cleaned out without disturbing any pipes and can do no harm to the construction of the Boiler, and far better results can be obtained than can be got from an ordinary Boiler attached to an Indirect Hot Water storage cylinder or Hot Water calorifier.
The table given below shows the heating power in B. T. U. ‘s, and gallons of hot water per hour, and customers desiring to use this Boiler for Heating as well as Domestic Hot Water Supply should give the necessary particulars of their requirements to enable us to advise which size Boiler is most suitable.
The total heating power can be divided between heating and hot water supply in any proportion desired.