Challenge is fitted with a triple burner wet back Scotch type boiler. This type of boiler were extremely common and built in vast numbers.
It is 16ft in diameter and 11ft from front to back. When it is working it contains 32 tons of water. From cold the boiler will take approximately 2 days to get to full operating pressure.
Great care has to be taken to warm the boiler gently in the first stages of firing because as the boiler gets hot it expands at different rates in different areas, for example the area around the furnace will get hot before the top of the boiler, this can cause distortion. When it was coal fired this was fairly easy as you could regulate the amount of heat from the fire. But oil fired furnace is operating at near full temperature as soon as you light it. so it is fired in short bursts to start with.
 | The Todd burner instructions 1 |
| The Todd burner instructions 2 |
| The Todd burner instructions 3 |
| The Todd burner instructions 4 |
