Redring LP fault codewhat it means and how to fix it
LP 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.
Take care
What LP means
This is a Selectronic Advanced display, and Redring pair it with a slow flash on the Start/Stop button light. Their wording is abnormal flow rate, the water supply is less than 2 litres a minute, and the instruction is to contact Redring Support. The logic behind it is the third of the three protections they describe for a shower fed with too little water: below two litres a minute the power to the elements is switched off but the solenoid valve stays open, so water keeps flowing through the unit and out of the handset, just cold. That distinguishes LP from ot.
With ot the water stops; with LP it carries on, unheated, and the display tells you why. The earlier Selectronic Premier does the same thing at one litre a minute but has no LP display for it, so on a Premier the same condition looks like a shower that runs cold on a poor supply.
Because the shower is measuring the flow that actually reaches it, LP is a statement about the pipework and the mains as much as about the appliance. It appears when a stop tap or a servicing valve has been left part closed, when the cold mains is shared with something that has just started drawing hard, when the inlet filter has silted, or in a property where the mains pressure has always been marginal and the Advanced is simply the first shower honest enough to say so. It also appears when the flow transducer, the little turbine that measures the flow, has stuck, because a turbine that does not spin reports no water whether or not water is there. That last one is the reason Redring send you to them rather than to the stop tap.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| Servicing valve or stop tap not fully open | A quarter-turn isolator on the shower feed left half shut after plumbing work is enough. The flow is measured after it, and LP is the result. | Common |
| Low or shared mains pressure | A kitchen tap, a washing machine fill or a garden hose on the same cold main can take the shower below two litres a minute while it runs. | Common |
| Inlet filter silted up | Redring fit a strainer in the inlet fitting and recommend periodic cleaning by a competent person. A blocked strainer starves the shower even on a good main. | Occasional |
| Flow transducer not spinning | The professional checklist has the engineer check the internal blade spins when water flows and replace the transducer if it does not. A stuck blade reads as no flow. | Occasional |
| Airlock or debris after a supply interruption | Mains work in the street sends air and grit down the pipe. Both show as LP until the supply clears, and the grit ends up in the filter. | Rare |
What to try yourself
Run a cold tap fed from the same mains and judge the flow. A weak tap means the problem is the supply to the house or the stop tap, not the shower.
Find the isolating valve on the shower’s cold feed, usually a slotted quarter-turn valve near the unit or under the bath, and check the slot is in line with the pipe, which is fully open.
Make sure nothing else in the house is drawing cold water, then restart the shower with the Start/Stop button and see whether LP clears.
If LP is intermittent and follows another appliance filling, the mains is marginal. That is a plumber’s question about pressure at the house, not a shower repair.
If LP stays on with a strong cold tap and an open valve, the inlet filter or the flow transducer is the likely cause. Both are behind the cover, and Redring’s instruction for LP is to contact them.
Do not remove the cover to reach the filter yourself. The inlet filter check is on Redring’s professional list for the Selectronic, under a capitalised warning to switch off the electricity at the isolator before the front cover comes off, and their filter instructions for the rotary-dial ranges call it work for a competent person.
Get a qualified electrician to look at your Redring LP
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–£140
Time on site
15 minutes
Nothing if it is a part-closed valve or another outlet running. A filter clean or a flow transducer is a visit and a small part; a mains pressure problem is a plumbing job priced separately.
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
- Runs for five seconds then switches offGet it checkedA 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.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 about Redring LP
Does the older Selectronic Premier show LP?
No. The Premier has a single-digit display and no LP. It cuts the elements below one litre a minute and keeps the water flowing, so the same condition shows as a shower running cold rather than as a code.
Is LP the same as the Bristan or Triton low-pressure warning?
Same idea, different threshold and different response. Bristan and Triton have their own pages here. Redring’s figure for the Advanced is two litres a minute and the elements switch off while the valve stays open.
Will a bigger shower fix low pressure?
It will make it worse. A higher-kilowatt shower needs more flow to keep the water at temperature, not less, so a supply that trips LP on an 8.5 kW unit will do the same on a 9.5.
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.