cleaned as detailed in the ‘Gas System’ section.
For the first couple of minutes keep the burner on low. This is important,
as until it warms up, the flame will be a little unstable and turning it up
too much could cause it to go out. Also, with a completely full tank, liquid
gas could be drawn off instead of vaporised gas, which can also
extinguish the flame. After a couple of minutes, the gas control valve can
be opened more to speed up steam raising. Open the gas regulator slowly
to about one full turn. The full range of adjustment (closed to fully open)
is achieved within the
first full rotation
of the gas regulator knob any
more is unnecessary.
RUNNING THE LOCOMOTIVE
When full working pressure has been reached (between 35 and 40psi), the
safety valve will start to blow off steam. Steam generation can be
controlled by the gas valve in the right hand side of the cab. If the safety
valve blows off frequently during running, then too much steam is being
produced, which wastes water and gas. Turning down the burner will
decrease the amount of steam created. Conversely, if steam pressure is not
maintained during a run, then the burner should be turned up. After a few
minutes of running it may be noticed that the gas pressure through the
burner has increased. This is due to the gas tank becoming warmer and so
increasing the gas pressure. Simply turn the gas down – this may need to
be performed several times during a run. The art of balancing steam
generation to the operational requirement by the adjustment of the gas
control valve will quickly be learned.
The gas tank has a duration of about 25 minutes, though this will vary
depending on the gas valve setting. The boiler should not be allowed to
run dry, and a water gauge and boiler top up are fitted to allow you to
monitor and maintain the water level (see the ‘Water Top Up System’
section). When the gas is fully used up, the steam pressure in the boiler
will be seen to gradually drop until the loco comes to a halt. Should the
water expire before the gas is fully used, the pressure will drop rapidly
and the loco will stop. Check the pressure and water gauges – if pressure
is at zero and no water is visible in the gauge, turn off the gas. No damage
will result if the gas is turned off immediately and the loco left to cool
naturally. Do not add cold water to a hot, empty boiler. Never re-fill the
gas tank without first re-filling the boiler.
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