Clogged drains are frustrating. These simple steps can help you find the problem.

Step 1: If the problem is with one appliance, whether sink, shower, tub or toilet, chances are it is a simple clog in that one line. Confirm this by testing other drain lines to assure they are working. Food, hair and foreign objects are the most common causes for clogs. Manually removing the clog with a plunger or drain auger is the best solution.

Step 2: Gurgling sounds followed by slow draining and the smell of sewer gas is a good indicator that a plumbing vent line is clogged. Vent lines can be cleaned from the roof top using an appropriately sized auger.

Step 3: If multiple drains are affected, but not all drains, there is probably a clog farther down. Knowing where the main drain line exits the house and which drains are affected will help determine where the clog is. It may be necessary to access the clog with an auger from multiple directions to clear the line.

Step 4: When all appliances are affected or when the plumbing appliances nearest the exit point of the main drain line are backing up, chances are there is a clog in the main sewer line outside. Main line clogs can be tricky to diagnosis, as they can randomly cause toilets or washing machines to back up into sinks or showers, or they can simply cause all drain lines to run slowly. Rent an electric drain cleaner or call a pro.

Step 5: Roots growing through drain lines are the most common main drain issue. Having the lines professionally cleaned and treating the lines annually with copper sulfate can keep the problem at bay.

Step 6: Problems that occur following heavy rain are a good indicator that the main drain line outside is cracked. Water or sewage that is unable to seep into the rain-soaked soil will flow back into the home, up the drain line and out of the nearest appliance. Sewer line replacement may be the best option.