Look in the inlet of the new head before deciding it is faulty. Most carry a moulded plastic flow restrictor fitted to meet a water-saving figure, and on many models it is designed to come out.
The three causes, in order
1. The restrictor. A small coloured plastic insert in the inlet, behind the filter washer. The manufacturer’s instructions say whether it is removable on that model.
2. The filter washer. A fine mesh under the cone seal. It catches grit dislodged when the old head came off, which is exactly when it blocks.
3. The head is bigger than your pressure. A larger face spreads the same flow over more area. That is not a fault, and no adjustment fixes it — a smaller head does.
What is almost never the cause
The hose, unless it is visibly kinked. And the tap, unless something else changed at the same time.
The check that separates them
Run the shower with the head unscrewed, into a bucket. Strong flow from the bare hose means the head or its restrictor; weak flow means the problem is upstream and the new head is innocent.
Questions people actually ask
Is removing the restrictor allowed?
It is a decision for you and for what your maker states. Some are designed to be removed and the instructions describe it; some are integral. Where water is metered or restricted locally, that is a separate consideration.
Why did the old head feel stronger with the same restrictor?
It probably did not have one — restrictors became common recently. Comparing a new restricted head against an old unrestricted one is the usual reason for the complaint.
Last reviewed 5 September 2026