Why Won’t My Sink Drain?

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Why Won’t My Sink Drain?

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When your sink is draining slowly, you know a complete stoppage is bound to happen eventually. There are several possible causes of a slow drain. Below are some of the most common causes, including a few of which you may not be aware.


This is usually on the top of everyone’s list. Many people think that just a little bit won’t cause a clog, but grease tends to stick to pipes in places. Every little bit only adds another layer and eventually causes a problem.


You may think that soap helps any debris just slide on through the pipes, but when soap mixes with minerals in your water, it forms scum. That scum isn’t just a film that you need to scrub off your shower; it also builds up in your drain system. If you have hard water, this process happens even faster. Certain household chemicals can also cause the same problem.


Even if you are careful to keep food scraps out of your sink, there still may be some bits of sticky rice or a noodle that escape and go down the drain. These can stick to your pipes or join other growing substances to form clogs. Hair that slips down the bathroom drains is also a culprit. Even razor shavings can collect around a growing clog to help create a blockage.


If the pipe leading from your sinks to your main drain doesn’t have the proper slope to encourage water movement, water flow is slower than needed. This encourages debris to stick to walls and other debris, forming potential clogs.


If the drain piping that leads the wastewater from the residence is clogged, that will definitely cause problems. If you have more than one sink balking, the culprit may be an outside drain pipe. The pipe can have a crack or even a piece broken out, letting in mud. While it could happen to any system, it’s more likely with older systems. The material of the pipe itself is also a consideration.


Sinks need air to replace the water moving through the drainpipe to prevent a vacuum from forming, slowing or stopping the flow. Air enters the system through vent pipes that extend from the roof. If one of these pipes should become clogged, the drain system will slow down. While these pipes don’t often get clogged, they can be blocked partially or wholly by fallen tree debris or even a dead bird. If the cause of the problem isn’t readily obvious or solved, the vent pipe may need to be checked.

When your sink is not draining properly, it’s time to act before the sink actually stops up completely. A plunger is usually the first step. However, if you have a double kitchen sink, it may turn into quite a project, as the side you are not plunging has to be sealed airtight to ensure enough vacuum for the plunger to work. A snake is usually a good choice for snagging hair and debris from a sink trap. However, if the hairball isn’t close to the sink, your snake may not reach. Additionally, if the problem is a grease clog, the snake may well bore a hole in the clog, providing temporary help, but it won’t remove the whole clog and it will eventually close up again.


These can be clogged by some of the same problems as sinks, such as trouble in the drainage pipe or a clogged vent pipe. Other causes include:


You know how hard it is to keep a toddler from dropping things in. Any foreign objects should be fished out if possible, rather than being flushed down.


People often have mistaken ideas about what is and is not flushable. Baby wipes, for example, are some of the more common items that are flushed; however, these are definitely not flushable. Even the ones that claim to be flushable can cause major backups or contribute to one. Kitty litter that is touted as being flushable is also questionable.


If a septic system is not turning over fast enough to handle what’s emptied into it, your toilet will let you know. Household chemicals can kill the bacteria necessary for a healthy tank, slowing the action.

If you have slow or clogged drain problems or a balky toilet, you can spend a lot of time and sweat trying to fix it yourself or even just discovering the cause. Your best bet would be to call a professional. Royal Flush Plumbing in Adelaide is experienced in handling all kinds of plumbing problems and has unclogged plenty of drains. They are adept at finding the problem, whatever the source, and setting it right.

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Luis M., Alberton
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I’d just like to send a little thank you note. After months of a variety of plumbing problems, you saved my pipes. After the team you sent was done with their work, sure enough, my drains were draining perfectly. I’m very grateful and I’ll certainly be recommending your plumbing services to my friends!
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I had issues with my toilet drain blocking up at my place of business, Royal Flush came out and saved the day on a Sunday morning before an event I had planned Later on in the evening. I had a chat to Matt about renovating the toilet and adding on an additional toilet and a new shower/bathroom and to my amazement he made this happen and I couldn’t be happier. Royal Flush, nit only provided the plumbing removal and install of this little project….
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Promina Inc


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