From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Graph of Calorstat effort versus water temperature for a standard Bentley radiator, showing shutter positions.
| Identifier | ExFiles\Box 87\1\ scan0208 | |
| Date | 4th November 1936 | |
| TESTS ON STD BENTLEY RAD. CALORSTAT CALORSTAT EFFORT / TEMP CURVES SHUTTERS CLOSED POSITION SPRING FITTED SHUTTERS OPEN WATER TEMP - °C 40 60 80 100 PUSH LBS 20 10 0 PULL LBS 10 20 G.S. Harrison 4/11/36 | ||