This article looks at how a washing machine fills with water when switched off. Sometimes overnight. When the washing machine is not in use, water may slowly rise in the drum. It could be with either clean or dirty water. It’s important to work out which type of water it is because they have different sources.
There are only 2 places where water can get into a washing machine’s drum. Either through a water valve, or through the drain hose. It’s impossible for water to get in any other way. If the water is very clean it must be coming in through a water valve. If it is dirty it may be coming in through the drain hose from the sink. Both possibilities are described in detail below.
Water coming in through a water valve
When a water valve isn’t being used it shouldn’t let any water through. It’s possible for a fault inside it to prevent one shutting off properly though. A small bit of grit or debris could also get past the filter and stop it from closing properly. It’s unlikely though unless it’s an old washing machine, or maybe there is some damage to the filter. Either of these issues can result in water slowly seeping into the machine.
Water rising inside the drum may only be noticed if the washing machine is left unused (with the water tap left on) over night, or over a several day period. This is why ideally you should always turn off the taps after using the washing machine.
Water Pressure Too Low
A third possible valve related cause is if the water pressure is very low. Bizarrely the valves rely on a minimum amount water pressure to push against a rubber flange and shut water off. You can get water seeping past the seal inside if the water pressure is extremely low.
The first thing to try is to turn off the taps
If the water inside the drum is clean, then water could be getting past the water valve. Turn off the water tap(s) to the washing machine. Does this stop the water coming in? If it doesn’t, move onto the drain hose possibility below. However, you must ensure the tap is not faulty by removing the fill hose from the machine and ensuring no water comes through with the tap turned off. This is the only way to be 100% sure water is being properly turned off. This is because a tap can be faulty inside and not turn off properly.
Try Seeing if Water is Dripping in Through the Soap Dispenser
Sometimes, by removing the soap dispenser drawer and carefully observing inside the soap dispenser you can see water slowly dripping in at regular intervals from the nozzles at the top. Don’t check this if the washing machine has just been filling though. You may get some dripping of water into the soap dispenser for a while after. If there is a slow drip you might also (but not necessarily) see a black jelly-like gunge around where the water comes in.
Check the Water Valve Filter
Water pressure to the valve might be reduced enough to prevent the valve shutting off properly if the filter is severely blocked. Turn off the tap(s), remove the fill hose(s) and the water valve filter is easily seen at the back of the valve. Usually it will be quite clean – with no need to remove it. If it is definitely blocked though carefully pull it out with some flat pliers. Clean it out under a running tap. Be very careful not to damage it! Even a very small hole will compromise its filtering abilities and let debris inside the valve.
Does the water valve need replacing?
If you can’t find a filter blockage, the water pressure is OK, and turning off the tab stops water entering the drum overnight you need to get the water valve replaced as soon as possible.
Water getting in through the drain hose
The only other place water could possibly get into the drum is by siphoning up the drain hose. This shouldn’t be possible if the drain hose is plumbed in properly. However, incorrect fitting can create circumstances where water runs down the drain hose or is siphoned up through it. Water is pumped through the drain hose out to the drain by one of 2 different ways –
- To a spout on the u-bend under the sink
- Down a stand pipe that the drain hose is pushed into
If the drain hose is connected to the u-bend
Water could be running into the machine from the sink if the drain hose is connected directly to the u-bend under the sink. If the water is entering through the drain hose from the u-bend the water might be smelly or dirty. Check this article for details Check the drain hose is installed properly.
If the drain hose pumps into a stand pipe
If your washing machine does not pump out into the u-bend it may be pushed into a larger stand pipe. You shouldn’t get this fault. There are rare circumstances where water could be sucked back into the machine though. For example, if the stand pipe is submerged in water through a blocked grate and the drain hose is sealed into the standpipe instead of sitting in it with an air gap around it. (Check the drain hose is installed properly).
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