Sprinklers, rotors & nozzles
Rotors vs sprays, nozzle arcs, pressure, and when to choose MP Rotator or fixed spray.
What is the difference between a rotor and a spray sprinkler?
Spray heads pop up and cover a fixed arc with a fan of water—best for small lawns and beds (typically ~5–15 ft). Rotors use a rotating stream for longer throws (often ~15–50+ ft) and lower precipitation rates, better for larger turf. Mixing sprays and rotors on the same zone usually causes uneven coverage because they apply water at different rates.
What is a Hunter MP Rotator?
MP Rotator nozzles apply water in rotating multi-stream patterns at a lower precipitation rate than traditional sprays, improving soak-in on slopes and clay. They thread onto spray bodies (like Pro-Spray) and are matched by arc and radius. Use matched precipitation sets on a zone—do not mix MP Rotators with fixed sprays on the same valve.
When should I use Hunter PGP or I-20 rotors?
PGP-style rotors are the workhorse for residential and light commercial turf. I-20 and similar commercial rotors add features like check valves, stainless risers, and broader nozzle trees for tougher sites. Choose by throw distance, pressure available, and whether you need a check valve to stop low-head drainage.
What pressure do sprinkler heads need?
Most spray nozzles want about 30 psi at the head; many rotors perform best around 40–50 psi (check the nozzle chart). Too little pressure shrinks radius; too much misting wastes water. Use a pressure regulator at the valve or head when static pressure is high.
How far apart should I space sprinkler heads?
Design for head-to-head coverage: space heads at roughly the radius of the nozzle so streams reach neighboring heads. Square or triangular spacing both work; triangular often covers large turf more evenly. Always verify with a catch-can test after install.
What does matched precipitation rate mean?
Matched precipitation means every head on a zone applies water at a similar inches-per-hour rate so corners (90°), edges (180°), and full circles (360°) finish evenly. Nozzle families are designed so quarter, half, and full nozzles balance when spaced correctly.
Why is my sprinkler head leaking from the top?
Worn seals, debris in the riser, or excessive pressure can cause weepage. Flush the line, replace the seal pack or head, and add a pressure regulator if misting is visible. Low-head drainage after the zone shuts off often needs a check valve body or check-valve stems.
What is a sprinkler check valve?
A check valve in the head or body stops water from draining out the lowest heads when the zone shuts off. Use them on slopes to prevent puddling and erosion at low heads.
Can I put an MP Rotator on any spray body?
MP Rotator nozzles fit standard female-threaded spray bodies (Hunter Pro-Spray and many competitors). Confirm thread standard and that the zone is dedicated to MP precipitation rates.
What is the difference between 5" and 12" pop-up sprinklers?
Pop-up height clears turf and groundcover. Use taller pop-ups (6–12") where grass is thick or beds have foliage that would block a short nozzle. Short 2–4" pop-ups suit hardscape edges and low turf.
How do I adjust the arc on a Hunter rotor?
Most Hunter rotors have a keyed arc adjustment: pull up the riser, insert the tool, and turn the arc adjustment screw or ring while the head is pressurized or per the model instructions. Set left and right stops so the stream covers turf without soaking windows or sidewalks.
Why are my sprinklers misting?
Misting usually means pressure is too high for the nozzle. Add a pressure-regulating spray body, a zone regulator, or a master pressure regulator. Also check for partially closed valves creating cavitation.
What nozzle should I use for a narrow side yard?
Use a strip or specialty nozzle designed for narrow rectangles, or a carefully aimed adjustable arc at reduced radius. Avoid full-circle rotors in strips—they waste water on hardscape.
Do I need a filter before sprinkler nozzles?
Municipal water is often clean enough for sprays and rotors, but well water, ponds, or reclaim may need filtration to protect nozzles and valves. Drip zones almost always need a filter.
What is low-head drainage?
After a zone turns off, water in elevated lateral pipes can drain out through the lowest heads. Check valves at heads or elevation-aware design reduce the puddles and erosion that follow.
When should I use a Hunter PGP Ultra?
Hunter PGP Ultra heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter PGJ?
Hunter PGJ heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter I-20?
Hunter I-20 heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter I-25?
Hunter I-25 heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter I-40?
Hunter I-40 heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter I-90?
Hunter I-90 heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter SRM?
Hunter SRM heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
When should I use a Hunter PS Ultra?
Hunter PS Ultra heads are selected by throw distance, available pressure, and site duty (residential vs commercial). Compare the radius/nozzle chart on the product page to your head spacing and GPM budget. For slopes, prefer models with check-valve options.
What sprinkler nozzle should I use for a 90° arc?
Choose a nozzle from a matched-precipitation family rated for a 90° arc (or an adjustable nozzle set to 90°). Pair it with heads spaced for that radius and keep the entire zone on the same nozzle family so corners and edges apply water evenly.
What sprinkler nozzle should I use for a 180° arc?
Choose a nozzle from a matched-precipitation family rated for a 180° arc (or an adjustable nozzle set to 180°). Pair it with heads spaced for that radius and keep the entire zone on the same nozzle family so corners and edges apply water evenly.
What sprinkler nozzle should I use for a 270° arc?
Choose a nozzle from a matched-precipitation family rated for a 270° arc (or an adjustable nozzle set to 270°). Pair it with heads spaced for that radius and keep the entire zone on the same nozzle family so corners and edges apply water evenly.
What sprinkler nozzle should I use for a 360° arc?
Choose a nozzle from a matched-precipitation family rated for a 360° arc (or an adjustable nozzle set to 360°). Pair it with heads spaced for that radius and keep the entire zone on the same nozzle family so corners and edges apply water evenly.
What sprinkler heads work for about 5 ft spacing?
For roughly 5 ft head spacing, pick nozzles/rotors whose radius chart includes 5 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 8 ft spacing?
For roughly 8 ft head spacing, pick nozzles/rotors whose radius chart includes 8 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 10 ft spacing?
For roughly 10 ft head spacing, pick nozzles/rotors whose radius chart includes 10 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 12 ft spacing?
For roughly 12 ft head spacing, pick nozzles/rotors whose radius chart includes 12 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 15 ft spacing?
For roughly 15 ft head spacing, pick nozzles/rotors whose radius chart includes 15 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 17 ft spacing?
For roughly 17 ft head spacing, pick nozzles/rotors whose radius chart includes 17 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 20 ft spacing?
For roughly 20 ft head spacing, pick nozzles/rotors whose radius chart includes 20 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 25 ft spacing?
For roughly 25 ft head spacing, pick nozzles/rotors whose radius chart includes 25 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 30 ft spacing?
For roughly 30 ft head spacing, pick nozzles/rotors whose radius chart includes 30 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 35 ft spacing?
For roughly 35 ft head spacing, pick nozzles/rotors whose radius chart includes 35 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
What sprinkler heads work for about 40 ft spacing?
For roughly 40 ft head spacing, pick nozzles/rotors whose radius chart includes 40 ft at your available psi, and design head-to-head. Shorter radii usually favor sprays or MP Rotators; longer radii favor gear rotors. Always verify with the product nozzle chart rather than the name alone.
How do I replace a broken sprinkler head?
Shut off the zone or main, unscrew the old body, wrap male threads with PTFE tape if required, thread on the replacement at the same height, and flush before installing the nozzle. Match pop-up height and nozzle family.
What causes a sprinkler to stick up?
Debris in the riser, sand in the seal, or missing system pressure to retract. Pull the riser, flush, clean the wiper seal, and verify the zone shuts off completely.
Should I use matched nozzles on a renovated zone?
Yes. Mixing brands/precipitation rates on one valve creates dry and wet patches. Replace a full zone’s nozzles as a set when redesigning.
How do I stop watering the sidewalk?
Reduce radius, adjust arc, switch to a strip nozzle, or move heads. Overthrow onto hardscape is wasted water and can violate local rules.
What is a shrub adapter sprinkler?
Shrub adapters elevate nozzles above planting without a full pop-up body—common in beds. They still need matched precipitation if tied to turf sprays (better: separate drip).
Can I use reclaimed water on standard sprinkler nozzles?
Often yes if the water quality meets filtration needs, but purple identification and local codes apply. Some nozzles clog faster on reclaim—filter aggressively.
How do I winterize pop-up sprinklers?
Blow out laterals at safe pressure so water leaves the cases, or drain per climate practice. Do not use extreme compressor pressure that ruptures seals.
Why does my rotor keep rotating past the stop?
Worn trip springs or arc mechanisms fail with age—rebuild or replace the head. Confirm you are adjusting the correct left/right stop while the unit is pressurized if the model requires it.
What is a high-efficiency nozzle?
HE or multi-stream nozzles apply water more slowly and uniformly than older fixed sprays, cutting runoff. MP Rotator-style nozzles are a common high-efficiency choice on spray bodies.
How often should I inspect sprinkler heads?
Walk zones monthly in season: look for tilt, clogging, leaks, and blocked spray. After mowing season starts, check for deck damage weekly on edge heads.