this isn't the first time i've smelled it. it's not super strong most of the time. sometimes i smell it very strongly and sometimes it's very faint. it's been smelling strong the past couple of days so i told my boyfriend and he got irritated cause he didn't smell it so he grabbed his lighter and lit it for about 10 seconds and nothing happened. if there was a gas leak, there would've been an explosion right? so the smell has to be because of something other than a leak right? we have a VERY old gas heater and it's probably never been cleaned before.