Guide · Drip emitters
Drip emitters not dripping or uneven: what to check
Drip emitter not working? Check the filter and pressure first, then clogged or buried emitters and long 1/4 in runs. Water-only cleaning and when to replace.
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Picks that fit
- Raindrip PC8010B 2 GPH pressure-compensating dripper (10‑pack)Check price on Amazon
- Rain Bird SW10/10PS 1.0 GPH pressure-compensating spot watering emitter (10‑pack)Check price on Amazon
- Rain Bird SW20‑30PS 2.0 GPH pressure-compensating spot watering emitter (30‑pack)Check price on Amazon
Short answer
If every emitter is weak, check the filter and the pressure first. If only some are, look for clogged or buried emitters and for the far end of long 1/4 in runs. Clean with water only: rinse the filter, flush the line ends, and replace any emitter that stays blocked.
Picks that fitAll picks and how to choose
Start with the whole system
When every emitter on a line drips less than it used to, the cause is usually upstream.
- The filter. DIG's troubleshooting checklist says to remove the filter and clean it under running water, and to open the ends of the mainlines and flush them during a manual run.[1] Utah State University Extension recommends inspecting and cleaning filters monthly during the growing season.[2]
- The pressure. DIG's checklist says most drip systems operate best between 20 and 50 psi, and names high pressure as the typical reason a drip system functions improperly.[1] Each emitter also has its own range, so compare your regulator's outlet pressure with the range your emitter maker gives. The regulators guide covers this.
Then look at individual emitters
When only some emitters are weak or dry, look closer.
- Buried emitters clog. Raindrip says its drip tubing should not be buried, because buried emitters risk clogging.[3] DIG recommends keeping drippers and 1/4 in dripline above ground or under mulch.[4]
- Long 1/4 in runs. A Utah State University Extension design presentation illustrates how pressure loss along 1/4 in tubing lowers emitter discharge farther from the manifold more than along 1/2 in tubing.[5] If the last emitters on a long 1/4 in branch are the weak ones, shorten the branch or feed it from the 1/2 in line closer to the plants.
- Clogging, even with "self-flushing" emitters. Rain Bird describes its PC on-line emitters as self-flushing yet still calls for 200 mesh filtration.[6] DIG asks for at least 150 mesh for its inline emitters.[7] UF/IFAS recommends filtering out particles down to one-fourth the size of the emitter's passageway.[8] The filter mesh guide shows how to match the mesh.
- Emitter models differ. A 2020 study ran four types of pressure-compensating button emitters for 980 hours and found three of the four showed satisfactory clogging resistance.[9] So one blocked model does not mean every model will block.
Why watering can be uneven
Utah State University Extension lists eight common causes of uneven irrigation: pressure variation, manufacturing variation, spacing, disrepair, clogging, weather, irrigation duration and soil infiltration.[10] Most of the fixable ones on a home system are pressure, clogging and disrepair.
Cleaning: water only
Rinse filters under running water and flush the line ends with the system's own water, as DIG's checklist describes.[1] We do not cover acid, chlorine or any other chemical cleaner. If an emitter stays blocked after flushing, replace it.
Diagnostic table
| What you see | Likely cause | What to check |
|---|---|---|
| Every emitter weak | Dirty filter | Remove and rinse the filter; flush the mainline ends |
| Every emitter weak or popping off | Pressure outside the range | Regulator outlet psi against the emitter's stated range |
| Last emitters on a 1/4 in branch weak | Pressure loss along the 1/4 in tubing | Branch length; feed it closer to the plants |
| One or two emitters dry | Clog | Flush; replace if still blocked |
| Emitters under soil dry | Buried emitter | Move above ground or under mulch |
| Wet patches between emitters | Leak or split | See the leaks guide |
Replacing blocked emitters
Use an emitter whose stated pressure range covers your system's pressure and whose inlet matches your tubing. DIG's PC button emitters come in .5, 1, 2 and 4 GPH, compensate between 7.25 and 58 psi and use a 1/4 in barb inlet.[11] Match the flow of the emitter you are replacing.
Picks that fit5 products
DIG PC button emitter: the 2 GPH green bag of 100, or B224B, the 4 GPH red 10-pack. Raindrip PC8010B: a 2 GPH pressure-compensating dripper, 10-pack.
More on choosing
Rain Bird spot watering emitter: 1.0 GPH in a bag of 10 (SW10/10PS) or 2.0 GPH in a bag of 30 (SW20-30PS), compensating from 15 to 50 psi and asking for 150-200 mesh. Pick the flow you are replacing. Keep at least 150 mesh filtration upstream. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or the brand.
2 GPH pressure-compensating button
2 GPH pressure-compensating dripper, 10-pack
Raindrip PC8010B 2 GPH pressure-compensating dripper (10‑pack)
4 GPH pressure-compensating button
1 GPH spot emitter, bag of 10
Rain Bird SW10/10PS 1.0 GPH pressure-compensating spot watering emitter (10‑pack)
2 GPH self-piercing spot emitter
Rain Bird SW20‑30PS 2.0 GPH pressure-compensating spot watering emitter (30‑pack)
Next
Questions
Why is my drip emitter not dripping?
If all emitters are weak, clean the filter and check the pressure; DIG says most drip systems work best at 20 to 50 psi. If one is dry, it is probably clogged or buried.[1]
Why do the emitters at the end of my line drip less?
Pressure drops along the tubing, more so in 1/4 in tubing than in 1/2 in, as a Utah State University Extension presentation illustrates. Shorten long 1/4 in branches or feed them closer to the plants.[5]
How do I unclog a drip emitter?
Flush with water: rinse the filter under running water and open the mainline ends during a manual run, as DIG describes. We do not cover chemical cleaners; replace an emitter that stays blocked.[1]
Do self-flushing emitters still need a filter?
Yes. Rain Bird calls its PC on-line emitters self-flushing and still recommends 200 mesh filtration.[6]