Hefeweizen Fermentation Time (on and on)

Ive been searching the threads for an answer to this my particular question with no joy.

My first Hefe had a low OG of 1.040 after boil. I boosted it with some dextrose to bring it to 1.044 before sending to ferment. Im now 14 days into fermentation and its still bubbling with quite a bit of head on it.

How long is to long with a hefe? Everyone seems to ferment for 7 - 10 days, but I dont think mine will stop fermenting until 21 days at the rate its going. Should I wait it out? Or bottle it? Ive never had any of my beers still fermenting this strong after 2 weeks, especially since this has been such a low temp of 62 degrees.

What Yeast did you use? I usually have fairly quick fermentation with HW's 7-10 days. We are at the will of the yeast.

Measure it and see if it changes SG. If not you could just be seeing co2 and the krausen hasn't dropped. But I'd wait it out. It won't hurt it. Otherwise you'll get bottlebombs. Not good unless you like recreating scenes from Breaking Bad.

When people say Hef's are best young, it a general term, as in they don't age them out 6+ months in a secondary.

A slow fermentation could also be due to a lower fermentation temperature. At what degree are you fermenting?

It is always my rule to let the yeast go and let them tell you when they are done. We recently brewed with 1056 and fermentation was steady for 10 days. I was surprised but it happens. It slowed down on day 11 but we also fermented at 64 degrees steady. The low temp is probably the cause of the long fermentation. It isn't a bad thing at all. You will probably end up with a very clean beer. Letting it rise a few degrees at this point my help them finish up and you will want to raise the temp to 70ish anyway so the yeast can clean themselves up. We personally go at least 2 weeks, at a minimum, after no signs of activity for all of our beers. Sounds like it will be a great beer. Let it finish.

Thanks everyone for the tips. I have bottled this and had a taste of one after 7 days. Very good. LOTS of sediment yet tasty all the same. Looking forward to it when its fully carbonated. My next goal is to learn how to clean my beers up a bit more. Thanks!