The way my heater used to work (as it should) I turn up the thermostat, I hear it click on, then I hear the flame ignite, then after it heats up enough the blower kicks on and out comes the heat.

Now to even get it to work, I have to turn the thermostat as high as it goes, even though I hear the click in the thermostat, I never hear the flame ignite. Then the blower kicks on for exactly 20 seconds, then off for exactly 45 seconds, then on for 20 and off for 45, all night long, never changes. When I look inside at the flame, it is always lit, it never goes down to the small pilot light like flame, it's just always on.

After 4-5 hours of this the temperature in the house is still only 70 degrees.

Any ideas?

** Also is this dangerous like this always being on, it looks pretty hot in there among the flames, like a couple things I see looks like it does when metal gets hot and glows a bit?