Furnace's fan is not working in "ON" position

[Vensi]

Hey everyone, we have the TRANE XV95 in our house. As we don't have A/C, the technician set the fan working only in "AUTO". In winter, we use our fire place and we need air flows through our house. But by turning "FAN ON" on thermostat the furnace's fan doesn't start spinning. All wiring connected as per installation book.
 
Question: Is it any problem with dip switches or jumper missing?
Furnace model: UH2B080A9V3VA
Dip SW setting:1-OFF,2-ON,3-OFF,4-ON,5-ON,6-OFF,7-OFF,8-ON

[Admin]

How many wires are connected at the thermostat?  Without AC it's possible you only have 2 wires.

You can jumper the R and G terminals at the furnace and the fan will run continuously.

[Vensi]

Thanks for your advice.
However, I don't need to run the fan continuously.
I'm looking for the fan working in TWO modes.
First-in "AUTO" mode when thermostat is calling for heat(winter time).
Second- in "ON" mode when the air flows through the house (summer time).
Any thoughts?

The thermostat is terminated with 4 wires:
Green-G   Yellow-Y (even no A/C in house)
White-W   Red-R with jumper to Rc.