The sensors aren't that expensive, the bigger challenge is getting the existing one desoldered and removed without ripping out a pad or trace. Since its junk anyway if I were going to replace it I'd just snip all the legs and carefully remove them one by one by heating and gently pulling it up out of the hole once the solder is molten. It can be done but it takes patience and the more soldering experience you have the better.
Ken
Ken you mean you don't have one of these Hakko super-suckers yet? shame