Jost Hot Air Engine Fan

 Jost Hot Air Engine Fan
1919  20” floor type “Jost Radio Fan”

Before electricity was widely reticulated, cooling fans powered by small hot air engines running on alcohol or kerosene were popular in hot countries.

It burns lamp oil in a wick type burner very similar to the type that is commonly used for kerosene lamps. 

People often point out the contradiction of using a fan run by a heater for cooling, but the personal cooling effect of moving air much exceeds the miniscule temperature rise from a small flame. 

There were many manufacturers of hot air engine (Stirling cycle) fans.  Some Indian and Pakistani models were still being made in the late 20th century.

Jost fans are regarded as being of the highest quality and were sold from around 1903 until 1923.  In earlier Jost models the fan was belt driven while this style, their most popular and most successful, uses direct drive.  It’s Stirling engine uses a gamma (two cylinder) layout often used for low temperature differential Stirling engines.  

Jost fans were manufactured by Hubertus Raab in Zeitz, Saxony (Germany).  Coincidentally, Raab’s factory was originally Paul Lochmann’s workshop where a small Stirling cycle engine commissioned by Sir Julius von Haast for what became Canterbury University was made in 1881.  This Lehman engine (made by Lochmann) is also in the Mahan collection.

Peter Lynn for the Mahan Heritage Centre, November 2023