A washing machine's Pressure Switch detects when the washer's water level reaches the correct setting. It does so by measuring the air pressure inside of a small tube connected to it. When a washing machine fills up with water, it needs a way to know when it's full.
How does the pressure system work on a washing machine?
How the pressure system works. As the level of water increases it forces air up the small tube and when sufficient air pressure is reached, the pressure switch will switch on telling the washing machine to stop filling and start washing. Conversely, when the water gets pumped away, water also drains from the bottle,...
How does a washing machine turn off the water?
As the washer fills, water enters the tube from the bottom and increases pressure in the airspace within the tube. When the pressure reaches the critical point, the switch shuts off water flow to the tub.
How does a water level switch work on a washing machine?
Water Level Switch Function. The water level switch sends power from the timer control to the water inlet valve and the temperature switch each time the tub needs to be filled during a wash cycle. As the tub fills, the switch cuts off the water flow when the water level inside the tub correlates with the setting for a large, regular, or small load.
Why is the pressure switch on my washing machine not working?
Another problem which can be attributed to the pressure switch is if you have a drum half full of water when set to a drain cycle and having turned off the machine, you are finding that the water is still siphoning away. This is actually due to the drain hose being set too low – so it's position is below the level of the water in the drum.
Where is the pressure switch on a washing machine?
The pressure switch on a washing machine can be found at the top of the machine , and it identifies how much water is in the machine - telling the control board if the machine has been filled or emptied. This video will help you to identify pressure switch faults and the ways to cure them.
How does air move up the hose in a washing machine?
When water starts filling your machine, air is pushed up the chamber and up the hose by the rising level of water in the drum. The air rises up the hose and activates the pressure switch - this will then tell the control module to activate the wash cycle to begin agitating the clothes.
Why is my water siphoning away from my washing machine?
This is actually due to the drain hose being set too low – so it's position is below the level of the water in the drum.
Why is my washing machine not spinning?
If your machine is not spinning it could be caused by a blockage in the chamber - which allows air to enter the chamber and the hose, but then not to leave.
When do pressure switches reset?
Some pressure switches have to be reset when the machine is moved or before the machine's first use. To do this put two litres of water inside the drum set the machine to a drain cycle and it will automatically reset the machine.
Can a washing machine hose be damaged?
Damage to the hose itself can cause problems as well. Your hose can possibly become damaged as sometimes what can happen in some washing machines is that the hose can rub against other parts of the machine, leading it to suffer from holes or other general wear and tear.
How does a water level switch work?
The water level switch sends power from the timer control to the water inlet valve and the temperature switch each time the tub needs to be filled during a wash cycle. As the tub fills, the switch cuts off the water flow when the water level inside the tub correlates with the setting for a large, regular, or small load. The switch then signals the motor to begin agitating.
How to tell if a washer has a water level switch?
You can distinguish the water level switch from other round switches inside the washer cabinet by its rubber tube that runs from the switch down the side of the tub . As the washer fills, water enters the tube from the bottom and increases pressure in the airspace within the tube.
What is a faulty water level switch?
A faulty water level or pressure switch is one such device. It can have problems due to blockage in its pressure hose, or it can have an electrical malfunction. You can clear the hose with a simple procedure, and you can test the switch for failure with a multimeter.
How does a washing machine work?
Modern washing machines now have a different pressure switch fitted that works with a coil and magnet but the principles are exactly the same in that they are operated by air pressure created by the rising water levels.
What is the tube on a pressure switch?
However, any pressure switch will always have a thin rubber or plastic tube connected to it that runs down to a plastic bottle at the base of the outer drum so that air pressure can switch it on and off. The word pressure chamber sounds grand, but it’s simply a plastic bottle.
What happens when water is pumped out of a washing machine?
When sufficient air pressure is reached, the pressure switch will switch on telling the washing machine to stop filling and start washing. Conversely, when the water gets pumped away, water also drains from the bottle. This releases the air pressure in the small tubing.
How many levels does a pressure switch have?
Some pressure switches only have one level , others have two (wash and rinse) and others may have three (wash, rinse and overfill). If you know how many levels it should have you can gently blow up the switch and check the number of clicks. The more wires connected to it the more levels it should have.
How does a washing machine control water levels?
How a washing machine controls water levels. All washing machines control water levels using the exact same system, which works on air pressure. It’s normally reliable, but when it goes wrong it can cause overfilling or flooding. Or problems related to filling and spinning.
How does water enter the pressure chamber?
As water enters the main drum, some of it also enters the pressure chamber bottle attached to the outer drum. As the level of water increases inside the bottle it forces air up the small tube.
