This film will show you how to diagnose the likely problem if the motor turns on and sounds fine, but then for some reason, the pump is not suctioning properly.

The suction pump forms a closed system made up of the tubes inside and outside the reservoir and filters.

When working properly, the pump motor sucks the air out of the system, creating a partial vacuum.

If the pump is working but there is no vacuum, there can be several reasons for this.

The first to check is the float valve in the reservoir lid. When the reservoir is full and needs emptying, the float valve blocks further suctioning. It is a safety feature to prevent overfilling the reservoir.

Normally, you would simply empty the reservoir, and the pump would start working again. But the float valve can get stuck. If it gets stuck while closed, it can permanently stop the device from suctioning. If it gets stuck while open and the reservoir is not emptied, liquid and fluid can get into the device.

The float valve is inside the lid. You remove it by twisting and pulling. There is a black rubber seal on the end, which blocks any liquid coming out of the reservoir. Make sure it is not damaged. If it is, you need to replace it.

You should be able to move the float up and down easily. If there is no movement, then the valve will not be working.

To replace the float valve, simply push it back into the slot until it clicks.

If that is not the problem, next check for any damage to the reservoir itself or the lid. Is the black seal inside the lid intact? If it is damaged, you need to change it.

Are there cracks in the lid or the reservoir through which air could enter? Does the lid close properly?

Blockages can also occur in the bacterial filter, which might need changing. Make sure the filter is on the right way around. It is designed to allow movement in only one direction.

Check that there are no signs of water having passed through the filter. You might see it discolored or there may be residue. If that happens, the filter needs to be changed as it represents an infection risk.

Also, if there is any sign of water damage on the filter, then it probably means the float valve is not working properly, and it may mean the water has also entered the internal tubing on the device where it may have caused blockages or damage.

If you have not found any problems so far, then it is time to open up the machine and look inside. Make sure you turn the device off and unplug it.

Once open, check for any signs of liquid damage. If there is none, then check if all of the tubes are in the correct place and that none of them are broken or have a blockage.

If there is any sign of liquid damage or you can see any liquid in any of the tubes, then you will need to take the machine apart and clean it.

If you find no leakages or blockages, then another potential problem may be with the regulator knob. This regulates how strong the suction should be, and it can become damaged. We show you how to check and replace this in a later video.

Finally, if you have not found anything wrong with the device so far, then the problem is likely to lie within the pump motor itself. There is a diaphragm which is quite easily damaged.