Quooker boiling water tap – how to descale, service and repair it

posted on 10 Apr 2019

Quooker taps are a very convenient way to always have boiling water on demand. They contain a small tank that stores water at boiling temperatures. That creates an obvious problem in hard water areas – scaling.

Today I will show you a typical repair to a Quooker tap that is suffering from leaks caused by heavy scaling. Quooker taps consist of small hot water cylinder and a tap. Cylinder and the tap have their own flexible hoses (there are 2 hoses) connected by a compression fitting. It is very common for scaled cylinders to cause leaks on this very connection. When that happens it is time to oder service kit from Quooker. Service kit consists of:

  • new immersion heater
  • new activated carbon filter
  • new flexible connector for hot water cylinder
  • tools required for servicing
  • cleaning tool and cleaning pads
  • new tap nozzle

Picture below shows immersion heater with filter, flexible connection hose and installation manual:

new immersion heater and filter with installation manual

Kit is also supplied with tools and cleaning pads required for the job as well as new nuts and nozzle for the tap:

tools, washers and nuts supplied with service kit

Quooker tap servicing sequence

In our example I am servicing a 12 years old Quooker Pro 3. We start by isolating power to the unit. Next step is to isolate water supply and drain tank from all pressure by opening the tap fully and waiting for it to stop relasing any water or steam.

Next step is to disconnect two flexible hoses between the cylinder and the tap followed by disconnecting secondary power supply to the unit contorls form DC adapter.

Once water is drained, supply of water isolated, spur switch turned off and supply from DC adapter disconnected we can remove the unit from the bracket.

There are 2 hex screws that are located on the top of the unit. We need to undo those.

removing 2 hex screws holding top plate

Put 2 screws aside and lift top cover expsoing insulation. Now we have to remove no.2 push fit electircal connectors.

insulation and no. 2 push fit connectors

Image below shows electrical connections disconnected

top plate removed

Next, gently lift insulation (it is 2 pieces of insulation) and put aside

insulation set aside

Picture below shows Quooker cylinder with removed insulation and exposed nuts holding immersion heater and water filter. Next step is to remove no.8 nuts with supplied box spanner.

removing heater and filter assembly

Once all nuts are removed they can be discarded as new ones are supplied. We are ready to gently lift the immersion heater and filter assembly out of the unit. Short video below shows that operation. This is when we find out the ture extent of scale problem with this unit.

This is the amount of scale that fell out of the cylinder. There was still much more inside the unit that had to be scraped out!


Service kit is supplied with a tool designed to clean edges of the cylinder so that new seal makes a good and watertight contact. Once the edges are clean it is time to boiler some water and descale inside of the unit.

descaling with Oust and boiling water

Flush unit with water and now it is time to assemble the unit with new parts. It is very simple, just drop new immersion heater assembly in, tighten 8 new nuts to secure it in place. Put insulation back in place. Connect no.2 electrical connectors from the top plate. Screw to hex screws on top plate. Now your unit is fully assembled and ready to go back on its bracket.

New assembly installation
Insulation put back in
Top cylinder plate screws going in 

Re do your water connection and connection between unit and tap. Use new washers supplied with the service kit. Cylinder to tap connection below.

New cylinder hose connected to existing tap hose

Now it is time to replace boiling water tap nozzle.

Existing tap nozzle being replaced

Turn water supply to the unit back on and test for leaks. Connect DC power supply to the back of the top plate. Turn power at the spur swith on.

You can now turn the boiling water tap on and drain it. Water will be balck for a short while as it flushes through activated carbon filter. Wait for the cylinder to get to the temperature (led on the tap will go off) and drain the tank again.

Your tap is now fully serviced, descaled and ready for use.

Have you tried descaling your own Quooker tap? Was it an easy job? Maybe your tap is not working correctly or leaking? Any questions please leave a comment and in case you are in London and do not want to do this job yourself just get in touch and I will be more than happy to provide quote for a full service and descaling to your Quooker boiling water tap.

For Qooker installation and servicing please contact me here: plumber Crystal Palace