Replace a Shower Pump — Trade Method
Replacing a shower pump is a 30–60 minute job with the right kit and confidence to isolate the water. This is the exact sequence UK plumbers use — including the pressure-test step DIY guides usually skip.
Step-by-step method
1. Isolate the cold feed from the loft tank and the hot from the cylinder
Isolate the cold feed from the loft tank and the hot from the cylinder.
2. Drain down at the shower and disconnect flexi hoses
Drain down at the shower and disconnect flexi hoses.
3. Undo electrical fused spur — ISOLATE at consumer unit first
Undo electrical fused spur — ISOLATE at consumer unit first.
4. Fit new twin impeller pump on rubber mounts to reduce noise
Fit new twin impeller pump on rubber mounts to reduce noise.
5. Prime by opening the shower before mains restoration
Prime by opening the shower before mains restoration.
Frequently asked questions
Do I need a plumber to replace a shower pump?+
Not legally — shower pump replacement is not notifiable. But if you cannot confidently isolate the water, get a quote (typically £70–£140).
What size shower pump do I need?+
UK domestic standard is 15mm compression tails. Check your existing fitting first — some older builds use 22mm or imperial 1/2" BSP.
Is the new part guaranteed?+
Reputable brands (Reliance, Pegler, JG Speedfit) offer 5–25 year guarantees on their fittings when installed to instructions.