Redring Runs for five seconds then switches offwhat to check
A Selectronic that starts, runs for about five seconds and stops by itself has not seen water flowing. Redring name the flow transducer and, before it, the supply.
Take care
What this means
Redring describe this from both sides of their two-tier table. In the owner’s Self Help list it appears as a note under water not flowing: if there is no water flowing then the shower will automatically switch off after about five seconds, and the check is that the water supply is turned on. In the Professional Service list it is its own line: shower runs for about five seconds and then switches off by itself, flow transducer fault, check that the internal blade spins when the water flows and if not replace the transducer. Put together, that is the whole diagnosis. The Selectronic measures flow with a small turbine, the flow transducer, and it will not energise elements it cannot prove have water passing over them.
When Start/Stop is pressed the solenoid opens, the display shows the target temperature for a couple of seconds, and the control waits for the turbine to report flow. If nothing arrives within about five seconds it shuts the valve and switches off, because heating a dry heat exchanger is the one thing it must never do.
So the shower is not faulty for stopping; it is reporting that it has not seen water. Either the water really is not reaching it, a closed stop tap, a servicing valve left shut, mains off in the street, an airlock after plumbing work, or the water is arriving and the turbine is not turning, jammed with scale or debris from the mains, its blade broken, or its pickup on the board dead. The first group is the owner’s and costs nothing. The second is behind the cover and is the part Redring name. The same logic explains a related complaint, a shower that starts, heats briefly and dies mid-shower: the flow dropped out for a moment and the transducer reported it honestly.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| Water supply to the shower turned off or restricted | Redring’s owner check. A servicing valve left shut after plumbing work, a stop tap knocked, or the mains off outside. No flow, so the shower stops itself at five seconds. | Common |
| Flow transducer blade not spinning | Redring’s professional line. Scale or grit from the mains stalls the turbine, and a stalled turbine reports no water whether or not water is there. | Common |
| Airlock after a supply interruption | Air in the pipe reaches the shower before the water does. The turbine sees nothing, the shower gives up, and a second or third start often clears it. | Occasional |
| Solenoid valve not opening | If the inlet valve does not open, nothing flows and the result is identical. Redring’s engineer check is the circuit through the solenoid coil, then the logic PCB. | Occasional |
| Flow transducer pickup or board input failed | The blade spins but the signal does not arrive. Rarer, and found only once the transducer itself has been tested. | Rare |
What to try yourself
Check the water is on: run a cold tap fed from the same main, and find the shower’s servicing valve and confirm the slot is in line with the pipe. This is Redring’s owner check and it is the usual answer after any plumbing work.
Press Start/Stop again two or three times, allowing the shower to time out between attempts. An airlock left by a supply interruption often clears on the second or third fill.
Listen during the five seconds. The solenoid valve should click open and you should hear water entering the unit; a shower that fills and still stops points at the transducer, one that stays silent points at the valve or the supply.
If water is definitely reaching the unit and it still stops at five seconds, the flow transducer is Redring’s named part. Leave the shower off and book the repair; the turbine is behind the cover.
Do not remove the cover to free the turbine yourself. Redring’s professional checklist is headed by a capitalised warning to switch off the electricity at the isolator first, and the flying lead to the front cover is easily damaged.
Get a qualified electrician to look at your Redring electric shower
We do not pass enquiries to a repair firm, so there is no form here. When you book a qualified electrician, tell them the make, the model and the exact code or message on the display, and ask whether they carry parts for this make — that is what turns one visit into a repair rather than a quote.
What it costs to fix
Typical repair cost
£0–£150
Time on site
15 minutes
Nothing if it is a closed valve or an airlock. A flow transducer is one of Redring’s listed spares, so it is a part and a visit rather than a new shower.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Own this appliance and had this code? . Nothing is published until a person has read it.
Related Redring fault codes
- LPGet it checkedLP on a Selectronic Advanced means the water supply has dropped below two litres a minute. The shower has cut its heaters rather than boil a trickle.Related: water-supply
- Filter or handset filling with solid materialGet it checkedRedring’s most unusual entry. They say this is not a shower fault at all and send you to a plumber to look at your water supply.Related: water-supply
- Water too COLDGet it checkedRedring answer this with eight checks in a deliberate order, and the seventh is the one nobody guesses: run the shower cold to reset the cut-out.Related: same brand
- otGet it checkedOver Temperature Shutdown on a Selectronic: the water got too hot, so the shower stopped it. Purge it cold before restarting, and stop using the isolator to switch off.Related: same brand
- Shower cycles from HOT to COLDGet it checkedRedring name one cause: the temperature is set too high, so the thermal cut-out keeps operating. Their fix is a dial adjustment done slowly.Related: same brand
- Water too HOTGet it checkedRedring give six checks, and the one that distinguishes them is a filter inside the solenoid valve that other brands do not send you to.Related: same brand
Own a Redring electric shower? Save it and its codes come first next time.
Related guides
Common questions
Is the whirring noise at the start connected?
No. Redring say a whirring noise at the start of every shower is normal: an internal motor adjusts the flow valve each time the shower starts. It is the five-second stop that matters, not the noise.
The shower stops after a few minutes rather than five seconds. Same fault?
Usually a cousin of it. A transducer that stalls intermittently, or a supply that dips when another outlet opens, reports lost flow mid-shower and the unit stops for the same reason. Note whether anything else was running.
Does the Selectronic show a code for this?
The Premier does not; it simply stops. On the Advanced, a supply below two litres a minute shows LP with the Start/Stop light flashing slowly, which has its own page.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer technical and service documentation
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.