If you have been lucky enough to never suffer having a blocked drain, then when you finally end up having to deal with one, it seems a daunting task as you stand there staring into the pool of grimy, greasy water wondering how you are going to unblock it. If you are unsure what to do, here is a small step-by-step guide that may help you before you call a plumber.
Ensure you have the right tools for the job. Gather them before you start to make the process easier. You'll want the following items to help you: Baking soda, lemon juice or white vinegar, a plunger, boiling water, and drain cleaner.
If the drain is slow but still flowing some, you can sometimes clear it with a baking soda flush. Put a half-cup of baking soda down the drain, then pour an equal amount of lemon juice or white vinegar in with it. Let it sit for several hours without running any water in that drain. The baking soda will foam, cleaning out whatever is slowing the drain flow. Then, rinse the drain with hot water for several minutes. This should restore the flow.
If the drain isn't flowing at all or is only minimally draining, place the plunger over the drain hole and begin to pump it up and down until the water in the sink has lowered if not fully gone. The force of the plunger may be enough by itself to move the clog along the pipe and get things flowing again.
Pour the boiling water down the drain, being careful to avoid splashing yourself so you don't get burned. Boiling water works because, in some cases, the cause for the blockage is accumulated grease and oil. Hot water is one of the main and most effective ways to dissolve it.
Now that you have rinsed the drain with hot water, pour a good quality drain cleaner down and leave it for the recommended time. The soaking time varies by drain cleaner brand, so make sure that you read the label carefully before you treat your drain. Be selective about the drain cleaner that you choose to use, because some drain cleaners will melt UPVC pipes and rubber washers. The last thing you want to do is cause yourself further plumbing issues.
Once the drain cleaner has had its allocated soaking time, rinse the drain according to the product's directions and your sink should be back in full working order.
If, after you have taken these steps, you find yourself still having problems, then it would be a good idea to look into getting a plumber to take a look as there might be a bigger problem elsewhere in the system