DIY washing machine repairs (part 7)

• Washing machine constantly fills with water and goes down the drain
• Washing machine is overfilling
• Washing machine fills with water overnight or when switched off
  • Full list of DIY washing machine help (parts 1 - 8) (Click the link then look on the right column)

 

Washing machine constantly fills with water and goes down the drain

If a washing machine constantly fills with water, the water has to go somewhere. It either floods out of the washing machine, or it siphons down the drain. The most important thing to try and work out is whether it is overfilling, or whether the washing machine filling all the time is caused by something else such as siphoning caused by incorrect plumbing.

If the washing machine overfills, the water level can be seen rising way above halfway up the door glass and eventually it may start to flood out of the back or out of the soap drawer. If this is happening to your washing machine then read washing machine is overfilling which deals with overfilling where water floods out of the machine as opposed to constantly filling with the water going down the drain.

Water constantly running down the drain, and the washing machine repeatedly topping up with water, can be caused by faulty plumbing. The washing machine may get stuck on a wash, or rinse program, caught in a cycle of filling with water and losing it down the drain. When siphoning has started it can stick forever in this cycle. NOTE: These symptoms can also be caused by totally different faults. Indesit washing machines (and some others) for example can force the washing machine into a constant cycle of filling with cold water and pumping the water away if it thinks the washing machine is overheating (possible faulty thermistor). The main difference is that in this scenario, the water is being pumped down the drain and the water pump can be heard running, whereas in siphoning, the water is just running down the drain through gravity.

Siphoning occurs when the end of the drain hose is lower than the level of the water inside the washing machine. It's exactly the same principal as siphoning beer out of a barrel into bottles or siphoning petrol from a tank. If the end of the drain hose is very low, then water can siphon out as soon as it enters the washing machine. If it's just slightly lower than it should be, then siphoning is usually triggered when the washing machine first pumps water out or even just occasionally.

This fault most often occurs when the washing machine has been moved out for cleaning or relocated in a new house etc. It can also occur if a drain hoses stand pipe isn't properly secured to the wall and falls over at an angle.

The drain hose should also not be pushed down too far down into the waste water pipe, which can cause siphoning just the same as if the stand pipe is too low. It needs to go just far enough in to prevent it falling out but it will fall out if not secured properly with a crook or tape. If the stand pipe that the drain hose is being pushed into is too low, then it may need raising. It could have fallen through the floor boards in which case you can gently raise it and secure it to the wall with proper brackets. If it was just installed too short, you can add a small extension piece.

You should ensure that the plastic crook supplied with the washing machine is fitted to the end of the drain hose. This forces it into a shepherd's hook. The length of drain hose sticking out of the crook should be about 4 or 5 inches. If the plastic crook is missing, I tape the drain hose in.

The Drain hose crook should be fitted at the end of the drain hose to prevent it slipping out, or conversely, going too far down the waste pipe. It is not required though if the washer pumps into a connection on the U-bend under the sink although if it is, the drain hose should be tied up so that it goes up several inches before running down to the washing machine pump to prevent siphoning ( see Make sure there are no problems with the plumbing ). Drain hose crook (4Washerhelp Spares - Note the drain hose crook is listed as fitting Hoover washing machines but it should fit any washing machine drain hose)

The height of the waste water pipe on the plumbing should be about 18 inches to 2 foot. Basically, the end of the drain hose should not be lower than the water in the tub. Full instructions for the exact height of the stand pipe should be available in the instruction book or on separate installation instructions.

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Washing machine is overfilling

A washing machine overfilling, will commonly have water pouring out of the soap dispenser drawer and / or out of the back. However, it is possible for these symptoms to be caused by several other faults not related to overfilling.

In theory, if a washing machine is plumbed in exactly as the washing machine manufacturer describes, and the washing machine overfills, then instead of the water pouring out of the washing machine, it should siphon down the drain. However, in practice, it is very rare for a washing machine to be plumbed in so perfectly, water going straight down the drain is more likely to be caused by a fault in the plumbing (see the section above this one)

If the washing machine is definitely overfilling then turn it off. If water still continues to enter the washing machine then either the hot or the cold water valve must be jammed open. In this situation the water must be turned off at the taps. They should be at the side of the washing machine, but many are fitted under the sink. Some water taps are wrongly situated behind the washing machine. If this is the case you will have to pull the washing machine out. The taps usually have a red and a blue identifier on them to signify which is hot and which is cold although relying on the colours assumes the plumber or installer has fitted them correctly, and I've seen hundreds where the red and blue indicators are the wrong way round.

If it stops filling as soon as you switch the washing machine off then the fault is with the pressure system that controls the water levels.

An overfilling washing machine is most usually caused by a blockage in the pressure chamber or more rarely a faulty pressure switch. A hole in the pressure chamber tubing linking the pressure chamber and pressure switch can cause overfilling. Pressure system faults can be tricky to deal with and the consequences of overfilling can be serious. I can't give specific repair instructions but here's how most washing machines control the water levels.

1. There is a pressure switch, which is a small device with several wires on it. This part is always at the top of the machine under the lid. It's round and near to the timer. It's a simple air pressure operated switch but some have 1 level switching, and others have 2 or 3 level switching (different switches operating at different air pressures)
2. At the bottom of this pressure switch is a plastic or rubber tubing hose.
3. This hose runs down to a pressure chamber which is fitted to the tub.
4. This is how it works -
5. As water enters the washing machine, it also enters the pressure chamber
6. As the level of the water rises, it enters the pressure chamber and forces air up the tubing. When sufficient air pressure is reached, the pressure switch will switch on. (Conversely, when the water is pumped away, the air pressure should release and cause the pressure switch to switch back off.)
7. This then cuts the power to the water valves and passes it on to the timer which starts washing.

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Washing machine fills with water overnight or when switched off

A washing machine filling with water overnight or when not in use has two possible causes. Either the water is running into the washing machine from the sink ( If the drain hose is connected directly to the u-bend under the sink ) or one of the water valves isn't shutting off properly and water is dripping slowly but surely into the washing machine. The latter problem can take several hours before the water level rises high enough inside the washing machine to be visible.

It's easy to track down the cause of water entering the washing machine when not in use. If turning off the hot and cold water taps stops it, then it's one of the water valves not shutting off properly, and needs replacing. It's just a process of elimination to find out which one it is. If not, the water is likely to be coming from the sink (use above link). Sometimes by removing the soap dispenser drawer and carefully observing inside the soap dispenser you can clearly see water dripping in at regular intervals.

Blocked water valve filters: I've come across cases where a filter in the water valve has become caked in a brown sludgy mud-like substance due to disturbances in the plumbing. This could be because of work carried out on internal plumbing or even after workmen have turned the water off in the street to work on the water mains. After the water is turned back on, muddy or gritty water can enter the household pipe work and when you use the washing machine it can draw this contaminated water into it.

In this scenario very fine grit or muck can get past the filter and stop it shutting off properly, or the filter is so blocked that water pressure to the valve is reduced enough to prevent the valve shutting off properly. Remove the water valve filter with some pliers and thoroughly clean it out. If the fault persists, replace the valve.

Important things to watch out for are -

1. Washing machine water valves need a certain amount of water pressure to actually ensure the water is shut off properly. Therefore, if your water pressure is very low, it can seep in past the closed valve. This problem is less likely to suddenly appear unless your water pressure has suddenly dropped. It's more likely to be a problem with a new installation. ( Related: Low water pressure and washing machines )
2. A faulty tap can mean that although you turn it off, the water supply isn't actually cut, so be careful of assuming if the fault still occurs, that you have definitely discounted the water valves. If unsure, you would have to disconnect the hot and cold fill hoses to ensure the water supply is properly cut when the taps are turned off. This problem is a lot more common with water taps that turn off with a red or blue plastic lever.
3. If the washing machine has just been filling, you may get some dripping of water into the soap dispenser for a few minutes after. Don't mistake this for a valve not shutting off properly.
4. If the water ever gets turned off while work is carried out on the water mains in the street or for major plumbing in your home, run lots of water in the house through taps at the sinks until it runs clear after the water is turned back on.

Faulty water valves should be replaced or there is risk of flooding.

More on next column ...

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