Hot side flow rate on new mixer Bathroom tap reduces automatically when opened!?

[eveares]

So I replaced my bathroom sink tap a couple of weeks ago due to my old one breaking.

(The plastic square protruding part of the mixer cartridge on the old tap snapped, could not source a suitable replacement.)

Got my new mono mixer tap from ScrewFix and since fitting it, I have noticed an odd quirk or issue with it. That being that when the hot water side is turned on, the flow rate automatically reduces until you open the tap further to a certain point.

Watch below for what I mean:

Is this behaviour normal as I never noticed it with my old tap what was a mini waterfall style tap? I have a modern Vaillant storage combi boiler if at all relevant.

Regards: Elliott.

 

[Steelmasons]

The tap is faulty , the initial water pressure pushes the washer off the seat until such time the pressure reduces and restricts the seating.
Tap washer when heated expands causing a restriction to seating is another issue with these taps.
The problem doesn't occur with the cartridge type.

 

[eveares]

So I need to get a new washer?

 

[Steelmasons]

No you need to remove the monobloc and ask for a replacement.
Welcome to our world when we have this problem , ballache ain't it.

 

[HERTS P&D]

That's why I get the customer to supply any taps that need to be fitted.

Andy