How to backwash an Intex sand filter
Updated: 21.10.2026
The pump is already beside the pool and the water has gone dull. How to backwash an Intex sand filter is the lever order, not a shopping list. You switch the pump off before the handle moves, you run the waste until it looks clear, and you add rinse only when the lid has a rinse position. New sand still has dust, so the first backwash is part of filling the tank. The [Intex sand filter](/hub/pool-care/intex-sand-filter) comparison is where the model was chosen. A qualifying amazon.co.uk purchase can earn us a commission at no extra cost to you.
The pump is already beside the pool and the water has gone dull. How to backwash an Intex sand filter is the lever order, not a shopping list.
The pump is already beside the pool and the water has gone dull. How to backwash an Intex sand filter is the lever order, not a shopping list. You switch the pump off before the handle moves, you run the waste until it looks clear, and you add rinse only when the lid has a rinse position. New sand still has dust, so the first backwash is part of filling the tank. The Intex sand filter comparison is where the model was chosen. A qualifying amazon.co.uk purchase can earn us a commission at no extra cost to you.
Our top picks
| Badge | Product | Valve | Sand load | Stated voltage | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Intex Intex 2800 GPH sand filter 26648BS | not stated in the bullets | not stated | 220–240 V in the title | 6.4 | about £194.49 | View offer |
 Intex Intex SX1500 sand filter 26644BS | Filter, backwash, rinse, recirculate, drain, close | 12 kg sand or 8.5 kg glass | 220–240 V | 9.1 | about £131.09 | View offer | |
| Alternative |  Intex Intex SX925 sand filter 26642BS | Filter, backwash, recirculate, drain | 6.5 kg silica, not included | not stated | 5.9 | about £109.99 | View offer |
On this page
Fill between the marks first
The English 220–240 V manual hosted by Intex Wetset says put the sand between the MIN and MAX marks and keep the centre pipe centred while you pour. If the lid has marks, fill between them. If the listing never stated a sand weight, use the marks rather than a kilogram from another code.
Seat the clamp before the first run, with the pump unplugged. New media throws dust, so backwash it to waste before you leave the valve on filter. A four-function SX925 and a six-function SX1500 are not the same list of positions. Read the lid. Valve type was the Intex sand filter buying guide.
Six-way order, then the four-function case
Intex Support's six-way sequence is specific. Switch the pump off. Move the valve to backwash. Open the drain cap. Run until the waste runs clear. Switch the pump off again. Move to rinse and run for at least one minute. Switch the pump off. Move to filter. Put the cap back on. That minute is the only timed rinse step. Judge clear water by looking, not by touching a live drain.
The four-way steps on that page have no rinse. The bullet on B09T71Y1ZC names filter, backwash, recirculate and drain. If rinse is not printed on your lid, do not borrow it from the six-way list. Stop after the waste runs clear, pump off, then filter, and put the cap back on. The SX925 safety sheet also says the pump is off before the valve moves, and not to use an extension lead. CLOSED is not a position you use while the pump is running.
Where the waste may go
Backwash water from a domestic pool is not automatically just rain. GOV.UK's guidance on domestic sewage discharges says a discharge of this kind is not domestic sewage on its own. Where it is reasonable, the foul sewer is the route, and you ask the sewerage undertaker before you discharge. Put a hose on the waste port before you switch the pump on. Keep it on through the rinse minute if the valve has rinse. In Scotland, Wales or Northern Ireland, ask the local undertaker. The valve order does not change.
What a backwash does not fix
A motor that will not start is not a valve setting. Reviews of B09T71Y1ZC include a pump that will not restart and flow that dies while the motor runs. Another minute on rinse does not rewind it. If the unit is faulty, that is a return under the Consumer Rights Act 2015. Sand in the pool can mean the centre pipe was not centred, or the fill went past the marks.
A 120 V pump is not cured by a backwash. B099LRF8ZK prints 120 V, and UK reviews describe a US plug. Stop, unplug, and use the Intex sand filter UK plug page. If the motor smells of burning, switch off at the socket and unplug. Do not fit a UK plug onto a motor whose table says 120 V. If the lid and the booklet disagree, check the model code with Intex.
Common questions
Do you switch the pump off before you move the handle?
Yes. Intex's backwash article and the SX925 safety sheet both put the pump off before the valve moves. You also switch it off between backwash and rinse, and again before you return to filter. Closed is not a running position. An extension lead is ruled out on that SX925 safety text as well.
What is rinse for, and what if the valve has no rinse?
On a six-way valve, rinse follows backwash. Intex says at least one minute, with the pump off before you move to rinse and off again before filter. It settles the media so the first return is not a pulse of dirty water. The four-way support steps have no rinse. If your lid does not print rinse, finish when the waste runs clear, then return to filter.
How full should the sand be?
Between the MIN and MAX marks, with the centre pipe kept centred while you pour. That is the English 220–240 V manual hosted by Intex Wetset. 26642BS asks for 6.5 kg, not included. 26644BS asks for 12 kg of No. 20 silica or 8.5 kg of glass. If the kilograms are blank, use the marks on the tank.
Where does the dirty water go in the UK?
GOV.UK treats this discharge as outside ordinary domestic sewage. Use the foul sewer where that is reasonable, and ask the sewerage undertaker first. Do not aim the hose at a road gully or a stream because the water looks clear. Keep it on the waste port through rinse if the valve has rinse.
Why is sand coming back into the pool?
Reviews of B09T71Y1ZC report sand returned to the pool, alongside pumps that will not restart. Check the fill against MIN and MAX and whether the centre pipe stayed centred. Backwash until the waste runs clear, with the pump off each time you move the handle. If sand continues after a correct fill, that is a fault to return, not a longer backwash.
Related pages
Sources
Sources for the buying notes, checked with the amazon.co.uk listings on 19 October 2026.
- Poolpro, Intex SX925 sand filter pump (retrieved 19.10.2026)
- Poolpro, Intex SX2100 sand filter pump (retrieved 19.10.2026)
- Intex SX925 safety sheet, via Poolpro (retrieved 19.10.2026)
- Intex sand filter pump valve positions (retrieved 19.10.2026)
- Intex Support, fibre-ball filtration media (retrieved 19.10.2026)
- Electrical Equipment (Safety) Regulations 2016, regulation 35 (retrieved 19.10.2026)
- GOV.UK, domestic sewage discharges to surface water and groundwater (retrieved 19.10.2026)
- Consumer Rights Act 2015 (retrieved 19.10.2026)