Snail wrote:Oh, so you're using electric heating vans when you couple modern carriages with old diesels that can't provide electric heating?
No, there is no electric heating wagons in Poland... Using diesels with passenger trains is a little complicated. It depends on diesel engine type.
In the rule, freight diesel engines have no heating system at all. You can use those engines only in combination with heating wagon and old passenger cars. Some diesel engines dedicated for passenger trains are equiped with steam boiler, which produces steam for heating. And some "modern" passenger diesel engines are equiped with electric generator, which allows use this engines with modern carriages. You can find all necessary information in OTTD purchase menu.
The same problem applies to old electric engines. The first polish electric engine (EP01) has no heating system. It requires additional heating wagon for passenger trains.