Vitodenns 050 29kw poor flow rate.

[Aire]

Hi guys.
I'm not familiar with viessmann at all but I'm fitting a bathroom and customer has mentioned poor flow rate from the hot water. The cold is perfectly fine but the hot is really poor. I've checked the cold inlet valve on the boiler and that's fine. I've looked through the manual but can't find anything. Is there a flow restrictor within the boiler that can be adjusted?

 

[Aire]

Nevermind, found the issue. Found the flow restrictor and the internal rubber o-ring had perished and the remnants were blocking the outlet. I'll order a new restrictor.