By the way, even the furnace does not starts,
the thermstat always shows that the heating system is on. I also can hear noise from the furnace once the thermstat shows that the heating system is on. However, the gas does not come out because the electric igniter does not become red/hot. If I shut down the furnace by the switch, and then turn it on, and if the electric igniter turns to red/hot, the gas will come out.