Sweet extract beer
 

So I am on my 8th batch of extract and I have have had great luck. But this is my second batch that has come out very sweet not in a row though. I've followed everything to a T and I have been very careful about cleaning and sanitizing. Anyone have a clue? I use a heat stick for boiling and always have. HELP?

Sounds like fermentation not complete, what was your fg?

Poor fermentation can leave it sweet. Make sure you measure your gravities and hit your numbers to be sure.

Are you fermenting where the temperature is stable? Large temperature swings or too cool temperature for the yeast can make your yeast quit too soon.

OFf flavor reasons for: sweet
http://morebeer.com/content/homebrew-off-flavors

Sweet
Tastes/Smells Like:
Overly sweet or sugary, sweet wort, cloyingly sweet
Possible Causes:
Some degree of sweetness is desired in most beers, but a beer that tastes like
unfermented wort is most likely the result of the yeast quitting prematurely. Stuck
fermentation is when the yeast ferments for several days and then suddenly stops.
The result is a gravity that is much higher than the correct final gravity for the wort.
Using yeast that doesn’t have a high tolerance for alcohol in a high gravity beer can
leave too much residual sweetness. A sudden drop in temperature can cause yeast
to go dormant and stop fermenting. Also, beer that is lacking the right amount of
hop bitterness can cause an unbalanced sweetness. Unbalanced sweetness is often
described as “cloyingly sweet”. Using too much fruit flavoring or other adjuncts can
cause a sickly-sweet beer as well.
How to Avoid:
Always use high quality yeast and make sure you are pitching the correct amount for
the gravity of the wort or make a yeast starter. Use the proper strain of yeast for the
style of beer being made. Highly flocculant yeast can sometimes fall out of suspension
before fermentation is over, however pitching enough yeast will usually prevent this. If
you are aiming for a dry, less sweet beer, use yeast with a high attenuation percentage.
If making a beer with very high alcohol content, it is very important to use yeast
nutrients. Monitor fermentation temperatures and avoid fermenting lower than the
suggested temperature range. It is possible to revive dormant yeast by gently swirling
the fermenter and gradually raising the temperature. Otherwise, pitching more yeast
is another option.
When formulating recipes, keep in mind that you can highlight a sweet or bitter taste,
but the balance of flavors is what makes a beer enjoyable. If using fruit extracts or
flavoring, start with a little and add more to taste.

When you want help it is always helpful to others if you post a recipe.