You can leave the pilot on overnight and it won't help. It is the secondary pilot that comes on when the temperature knob is turned up to at least to 350 degrees that puts the heat to activate the thermocouple bulb and then it can take up to 30 or 40 seconds for the burner to light after that. If it doesn't light then you might have to adjust the bulb to make sure that the flame is impinging on the bulb. The bulb might also have something on it that needs to be wiped clean and then try again. Give it a chance to light, even up to a minute.
Othertonka
2004 Southwind 32VS 8.1 Workhorse chassis
2002 CRV Toad
U. S. Gear Unified brake system
Retired Fire Captain, SFD