This film will show you how to diagnose the likely problem if the motor turns on and sounds fine but 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 the filter. When working properly, the pump motor sucks the air out of the system, creating a partial vacuum.

If it’s not suctioning, there can be several reasons for this. The first to check is the float valve in the reservoir lead. When the reservoir is full and needs emptying, the float valve stops further suctioning. It’s a safety feature to prevent over feeling the reservoir.

Normally, you would simply empty the reservoir and the pump will start working again, but the float valve can get stuck, permanently stopping the device from suctioning, especially if the reservoir has not been properly cleaned.

The float valve is inside the lead. You should be able to feel it move freely when you gently shake it or rock it back and forth between your fingers. If you can’t feel it move, then the valve is probably stuck.

If that’s not the problem, then next check for any damage to the reservoir itself or the lead. Are there cracks through which air could enter? Is the lead closing properly and forming a seal?

The same applies to the tubes inside the device. Are any of them damaged and letting in air? Are they all properly in place?

You also need to make sure the tubes are not blocked. Are the inlet and outlet ports clear? Any leak or blockage in the system will reduce the power of the vacuum and may stop the pump from suctioning altogether. Blockages can also occur around the bacterial filter, which may need changing.

Make sure the filter is on the right way around. It is designed to allow the air to move in only in one direction.

If if you find no leaks or blockages, then another potential problem may be with a regulator knob. This regulates how strong the suction should be and it can be damaged.

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

We’ll show you in other films how to assess and repair all these potential problems.