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How to set an impact sprinkler

Updated: 23 October 2026

You have turned the tap on, the arm has clicked once, and the head is now stuck pointing at the fence. This is how to set an impact sprinkler so the trip pin and the collars do the reversing. The steps follow Orbit’s adjustment guide and Rain Bird’s troubleshooting table, because UK reviews of the LATERN ET-A1609 and the GARDENIX say the leaflet was missing or useless. Those guides are for their own heads. Prices and patterns are on the [metal sprinkler comparison](/hub/garden-watering/metal-sprinkler). Peter F. used those listings and the public guides, read for 21 October 2026. A purchase through our links can earn a commission at no extra cost to you.

You have turned the tap on, the arm has clicked once, and the head is now stuck pointing at the fence. This is how to set an impact sprinkler so the trip pin and the collars do the reversing.

Our top picks

Winbay Winbay brass spike sprinkler

Best overall

Winbay Winbay brass spike sprinkler
8.4/10about £7.82
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FANHAO FANHAO impact sled

Alternative

FANHAO FANHAO impact sled
8.6/10about £35.99
View offer
LATERN LATERN impulse spike

Alternative

LATERN LATERN impulse spike
7.4/10about £9.99
View offer
On this page
  1. 1.Full circle or a sector
  2. 2.Throw, the diffuser, and a weak tap
  3. 3.How long, and when to stop
  4. 4.The oscillator is a different set of controls

Full circle or a sector

Start with the water off. On a typical impact head the trip pin selects the mode. Orbit’s guide, written for Orbit heads, says the lever up runs a full circle and the lever down runs a part circle, with two collars that you slide to the stops. Set both collars, not one. If the pin is down and the head still will not reverse, reviews treat that as a faulty trip rather than a setting you have missed. A twist nozzle will never reverse, because it does not walk. The Winbay and the lighter LATERN are that kind of spray. If the bullets say fan, cone, or stream, stop hunting for a pin and use the metal sprinkler buying guide to confirm you bought a twist barrel.

Throw, the diffuser, and a weak tap

The diffuser is the screw or pin that moves into the jet. Orbit says turning that screw into the stream breaks the jet and shortens the throw, on Orbit heads. If nothing clicks, pressure and leaks come before another twist of that pin. Orbit states that its impact heads may not run properly under 15 psi. That limit was not measured on the FANHAO, the STYDDI, or the GARDENIX. The lighter FANHAO states 20 to 80 psi, and UK reviews say it needs a lot of pressure before the arm spins. On that sled, a review says the inlet leaks until the rubber seal is pushed fully into the brass ring. A slack joint drops pressure so the arm will not reset. If you want litres per minute rather than a screw position, the bucket test is on the sprinkler for a large lawn page.
Winbay Winbay brass spike sprinkler

Testsieger

Winbay Winbay brass spike sprinkler
8.4/10about £7.82
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How long, and when to stop

The Royal Horticultural Society prefers watering in the morning. For a new lawn, set a jam jar on the grass and stop at about 13 mm, and only if restrictions allow a hosepipe. A leak at a plastic port, which reviews mention on the cheap LATERN impulse head, wastes water even when watering is allowed. Sort the seal before you time a jar.

The oscillator is a different set of controls

The GRÜNTEK does not use a trip pin. It is the oscillating bar in this set, listed at about £49.78, with sliders and a dial for width, throw, and flow, and a stated minimum of 2.76 bar. You set the rectangle by moving those stops. If the bar sticks in one place, UK reviews include units that stopped oscillating after a few uses and one that failed after about a year. The listing includes a cleaning pin and a removable metal filter, and one reviewer restored flow by cleaning a nozzle. That is maintenance for a blocked jet, not an impact adjustment. Several permanent heads, or a tap with no double check valve, are a job for the water company or a WaterSafe plumber.

Common questions

How do I set a part circle?
Turn the water off. Put the trip pin down for a part circle, using the Orbit layout as the usual pattern on this type of head, not as a manual for your brand. Slide both collars to the edges of the wedge. Open the tap and watch one trip out and back. One collar only lets the head hit a stop and stay there, which is what UK reviews describe on the LATERN impulse spike and the GARDENIX.
Why does it go one way and stop?
Rain Bird’s table, for its own heads, ties that fault to a trip spring, collar, or pin that is missing or left up. UK reviews of the LATERN ET-A1609 say it only rotates one way, and reviews of the GARDENIX say it does not return at the stopper. If the pin is down and both stops are fitted and it still will not reverse, the reviews point to a failed trip.
Which way do I turn the diffuser?
On the Orbit description, you turn the diffuser screw into the stream to break the jet and shorten the throw, and you back it out for distance. The FANHAO bullets describe a diffuser pin from mist to jet in the same spirit. These amazon.co.uk listings do not say how many turns equal a metre. If the arm is not clicking, fix pressure and leaks first. Shortening a jet that never reverses only makes a smaller stuck spray.
Should I water a brown established lawn?
The RHS says no. Do not sprinkle an established lawn just because it is brown. Brown summer grass is often dormant, and a metal sprinkler will not change that advice. Save the hosepipe for a new lawn, and only when a ban does not forbid it. A mature brown lawn is the case you leave alone.
What if the arm never clicks?
Confirm you own an impact head, not the Winbay or the LATERN whose bullets say fan, cone, or stream. Then check the trip pin, both collars, and whether water is actually reaching the head. On the lighter FANHAO, a review traces a dead arm to a seal that was not seated in the brass ring, or to a slack hose fitting that starved the pressure. If the mechanism is intact and the tap is open, return the unit.
Can I do this during a hosepipe ban?
You can read the steps. You should not open the tap if your water company’s ban covers watering a garden by hosepipe. Section 76 of the Water Industry Act 1991 allows that ban, the 2010 Order counts a lawn as a garden, and Ofwat describes a fine of up to £1,000. A carefully set sector is still hosepipe watering.

Related pages

Best metal sprinkler

Metal sprinkler

Metal sprinkler buying guide: pattern, then the tap

Impact or oscillating sprinkler: circle or rectangle

Sprinkler for a large lawn: the card versus your tap

Sources

Public UK sources listed in the research digest. amazon.co.uk prices, stars and review counts are the saved listing lines for these eight products. Last reviewed 22 October 2026.

  1. Water Industry Act 1991, section 76 (retrieved 22 October 2026)
  2. Water Use (Temporary Bans) Order 2010 (retrieved 22 October 2026)
  3. Water Fittings Regulations 1999, Schedule 2, paragraph 15 (retrieved 22 October 2026)
  4. GSS Regulations 2008, regulation 17G (retrieved 22 October 2026)
  5. Ofwat, hosepipe bans (retrieved 22 October 2026)
  6. Hozelock, how to measure your tap (retrieved 22 October 2026)
  7. RHS, watering (retrieved 22 October 2026)
  8. RHS, August lawns (retrieved 22 October 2026)
  9. Claber impact metal jet spike, via LBS (retrieved 22 October 2026)
  10. Easy Garden Irrigation, garden skid sprinkler pro (retrieved 22 October 2026)