One easy way to prevent drains from clogging is to introduce very hot water into the drain pipes on a regular basis. Dishwaters are a great example of this. Because dishwashers expel hot water from their wash cycle at high volume, they clear out gunk such as congealed grease and food before it has a chance to accumulate in any great quantity.
You can do the same thing with sinks and bathtubs. Simply fill the basin with the hottest possible water every couple of weeks, let the drain out, and then follow with about thirty seconds of hot water from the tap. This helps "blow out" the slime and junk that builds up and causes drain clogs. While not the best thing for your energy savings, it is a tried-and-true method for preventing future drain clogs.
If you have a main line clean out you have an additional way of verifying a sewer drain clog. Locate the clean out if you don’t already know where it is. Open the clean out by either unscrewing or pulling to remove the cap. Check the clean out for any waste or water that may be backing up there. You should not be able to see the water coming up the clean out pipe. If water is flowing up and out of the clean out or standing in the pipe this confirms that you have a main line sewer stoppage.
Once you have verified a sewer drain clog you can move on to clearing it. Clearing a sewer drain requires a sewer drain snake. You can either call a professional plumber or rent the machine and clear it yourself. Either way a sewer drain clog should be cleared as quickly as possible.
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