Jason there a few different Legend models. Temps and vac will vary some depending on size of blower and heat exchanger set ups. But all of them should heat up in about 15 minutes to max operating temps from my experience. They range from 200-240º at the machine but that reading is very misleading. The temp sensor is usually located right behind the exhaust heat exchanger. So you the user thinks that they have 200-240º but in actuality they have about 180-200º leaving the machine front disconnect. Then by the time they reach your wand you have about 160-190º. This would be your actual atw temps which is what really matters when it comes to cleaning efficiency. I suggest you pick up a TMF lie detector that measures temps at the front of the machine and at the wand. It should maintain *160-190º atw while cleaning. (*More on newest Legends)
Now if your machine is taking forever to heat even to the lowest temps mentioned above you could have a host of problems. Here are a few;
1) Machine is bypassing continuously.
2) Temp setting is off.
3) Heat bypass valve is damaged and allowing water to bypass.