What old sarge said is a good way to check the element. Another idea--if you use a temp probe inside the smoker box and you are getting up to temp in the normal heating time, then it probably is the wood. When I start smoking meat, it always takes about 45 minutes to complete the initial heating cycle up to 230-240*. If I started noticing that it was taking much longer to get through the first cycle, I would be thinking the element might be going bad.
My #2 is 9 years old, I believe, and I did replace the element a few years back--inexpensive and easy to do.