Hello, we have the hot & cold shower tap in our washroom and it leaks, possible due to winter. I cannot see how to take the top off the tap to check the internals (cartridge). There is a cover on the top, with the red & blue indicators, and it looks like the cover should come off, possibly revealing a screw to remove the top of the tap. Can anyone confirm before I damage it? Can I access all that I need to from the top, or do I need to become Houdini and unscrew the big nut underneath the tap and awkwardly located under the work surface and in the cupboard?

Ok, just figured this out. The cover is not removable, but the little red and blue tabs are. Difficult to get started, but they lift out easily enough once you've got something very thin underneath. There is a Philips screw underneath to take the top off and access the cartridge.

The later Eribas (this one = 2014) use Reich Kama taps in the kitchen and the washroom, if you didn't already know that.

The cartridge is out, but I'm not really sure what signs of damage I am looking for. I have ordered a new one for good measure, as it will be useful having one as a spare for either tap if I don't use it this time.

The tap is leaking from the bottom, as if where the 'tails' meet the tap itself. This results in water pooling in the cupboard below, but not up top on the work surface. The other thing I noticed about this tap is that it splutters, and this does not clear after the tap has been on for a while.

Does the spluttering always indicate an air leak, or could this be a symptom of a frost damaged cartridge?