On a cold day with the 'by-pass' open you have the benefit of the axle pump circulating water back into the tender which has been warmed on it's travels by it's proximity to the boiler.
This will keep the water around your gas cylinder at a nice ambient temperature which of course will help your twin burners to maintain suitable running pressure
Thanks SGA191
That engine on your video is most impressive.
Is it a private railway and where is the location (approx)?
main131 2 years ago
Nice locomotive, and some great stack talk there.
SBA191 2 years ago