squealing noise in bathroom mix tap and how to open up the tap

[wwtom]

The bathroom mix tap has developed a loud squealing noise. We suspect it's the problem with the washer by checking the related threads in this forum. But we need to open up the tap. Anyone knows how to open up the tap (the image attached), for which we don't have a clue yet. Many thanks.

 

[steadyon]

1. It won't have a washer, it will have a thermostatic cartridge for temperature control and a ceramic disc style flow valve.
2. May well have Allen grub screws inserted through holes in the undersides of the square knobs. Usually 2.0, 2.5 or occasionally 3 mm Allen key required.
3. If not as 2, above, will probably just pull off.
4. You will also probably need to remove the flat chrome plated wall plate to access the cartridges. Probably just fixed in place with silicone, but could be held by screwed rings behind knobs.

 

[wwtom]

Many thanks for your reply. I have taken off the screw, but it still doesn't come off easily. Any idea about how to pull it off?

1. It won't have a washer, it will have a thermostatic cartridge for temperature control and a ceramic disc style flow valve.
2. May well have Allen grub screws inserted through holes in the undersides of the square knobs. Usually 2.0, 2.5 or occasionally 3 mm Allen key required.
3. If not as 2, above, will probably just pull off.
4. You will also probably need to remove the flat chrome plated wall plate to access the cartridges. Probably just fixed in place with silicone, but could be held by screwed rings behind knobs.

 

[steadyon]

1. If you are talking about the knobs, they should pull off once the grub screws are removed. Just make sure there is no another grub screw under the first.
2. If you are talking about the wall plate, a further photograph with the knobs removed would be useful.