I have a furnace that comes on but sometimes it will not come on and I turn the thermostat off and the switch on the furnace off . I wait 10 minutes then turn it on and it works fine but it keeps on doing this. Do I have to drain the condensation out of the pipe? And how do I do this? Thank you

Is it a condensing furnace? The exhaust should vent downward to the exterior wall and the inside drain should go to a floor drain or a condensate pump. Where is the water collecting?