If your irrigation system was installed without pressure-regulated spray bodies, you could be wasting thousands of gallons of water every month. The H2OWize Retro-Regulator™ (HW-1800) is a patented, drop-in pressure regulator and check valve combination that installs directly into your existing pop-up sprinkler stems in seconds — no digging, no cutting, no gluing. Simply unscrew the cap, remove the existing internals, and press the Retro-Regulator into place. That's it. Your sprinkler is now pressure-regulated and leak-protected.
The Retro-Regulator is field-adjustable between 30 PSI and 40 PSI using a standard flathead screwdriver — two settings in one device. At 30 PSI, it delivers the ideal regulated pressure for standard spray nozzles, eliminating the misting, fogging, and wind-drift overspray that wastes water and causes dry spots. At 30 PSI, you can also convert the head into a drip irrigation outlet by replacing the spray nozzle with the H2OWize Nozzle Adapter (HW-1848, sold separately) and installing any low-flow bubbler or drip emitter. The integrated check valve prevents low-head drainage — stopping water from trickling out of the lowest sprinkler heads after the valve closes.
Compatible with 4", 6", and 12" pop-up spray bodies from Rain Bird® (1800 Series), Hunter® (Pro Spray), Weathermatic®, Orbit®, HydroRain®, K-Rain®, and Irritrol®. Note: Not compatible with Toro 570 spray bodies, heads with existing PRS installed, or rotor-type heads such as the Rain Bird 5000 Series or Hunter PGP Series. According to H2OWize, homes can reduce average watering bills by 30–50% per month after installation. If you're building a new system or upgrading to drip, DripWorks also carries a full range of inline pressure regulators and pressure-regulated spray bodies for new installations.
| Specification | Details |
|---|---|
| SKU (DripWorks) | PHW1800 |
| Manufacturer Part Number | HW-1800 |
| Brand | H2OWize |
| Outlet Pressure Settings | 30 PSI or 40 PSI (field-adjustable with flathead screwdriver) |
| Check Valve | Built-in (prevents low-head drainage) |
| Compatible Spray Body Sizes | 4", 6", and 12" pop-up spray bodies |
| Compatible Brands | Rain Bird® 1800, Hunter® Pro Spray, Weathermatic®, Orbit®, HydroRain®, K-Rain®, Irritrol® |
| Not Compatible With | Toro 570 spray bodies; heads with existing PRS; rotor heads (e.g., Rain Bird 5000, Hunter PGP) |
| Installation | Drop-in retrofit; no digging, cutting, gluing, or special tools required |
| Drip Conversion Capable | Yes — at 30 PSI with HW-1848 Nozzle Adapter (sold separately) |
| Estimated Water Savings | 30–50% reduction in outdoor watering costs per month |
| Patent Status | Patented design |
What does the Retro-Regulator actually do?
The Retro-Regulator is a drop-in device that adds two critical features to any compatible pop-up spray body: pressure regulation and a check valve. The pressure regulator reduces the water pressure at the nozzle to either 30 or 40 PSI, eliminating the misting, fogging, and wind-drift overspray that occurs at high pressure and wastes significant water. The check valve prevents low-head drainage — the common problem where water slowly trickles out of the lowest heads in a zone after the valve shuts off.
How do I install it?
Installation takes about 30 seconds per head and requires no tools (other than a flathead screwdriver to set the pressure). Simply unscrew the top cap of the sprinkler, pull out the existing stem and internals, press the Retro-Regulator into the flow tube of the spray body, and reinstall the original cap and nozzle. No digging, cutting, or gluing involved.
How do I choose between 30 PSI and 40 PSI?
Use a standard flathead screwdriver to adjust the pressure setting before installation. For most residential spray head applications, 30 PSI is recommended and is the standard setting for most spray nozzles. If you want to convert the spray body to a drip irrigation outlet, set the device to 30 PSI and pair it with the H2OWize Nozzle Adapter (HW-1848, sold separately) to connect a low-flow bubbler or drip emitter.
Which spray body brands and sizes is it compatible with?
The Retro-Regulator is designed for 4", 6", and 12" pop-up spray bodies from Rain Bird® (1800 Series), Hunter® (Pro Spray), Weathermatic®, Orbit®, HydroRain®, K-Rain®, and Irritrol®. It will not fit Toro 570 spray bodies, nor should it be used in spray bodies that already have a built-in PRS (pressure-regulated stem). It is also not designed for rotor-type heads such as the Rain Bird 5000 Series or Hunter PGP.
Will this work with my existing nozzles?
Yes. The Retro-Regulator fits inside the spray body and replaces only the internal stem/piston assembly. Your existing spray cap and nozzle remain in place and continue to function normally — just at the regulated, lower pressure.
How much water and money can I save?
H2OWize estimates that homeowners can reduce outdoor irrigation costs by 30–50% per month after installing Retro-Regulators. On a typical zone with 10 sprinklers running a 10-minute cycle at 70 PSI inlet pressure with 15' nozzles, the reduction can amount to approximately 800 gallons saved per month on that zone alone. Actual savings vary based on your local water pressure and utility rates.
Can I use this to convert a spray head into a drip emitter?
Yes — this is one of the most popular uses. Set the Retro-Regulator to 30 PSI, then replace the spray nozzle with the H2OWize Nozzle Adapter (HW-1848, sold separately). You can then attach any low-flow bubbler, drip emitter, or micro-irrigation device to the adapter and deliver precise, low-volume irrigation from your existing spray body infrastructure.
What if my system already has PRS spray bodies?
Do not install the Retro-Regulator in spray bodies that already include a built-in PRS (Pressure Regulated Stem) — for example, newer Rain Bird 1800-PRS or Hunter Pro-Spray-PRS bodies. These already regulate pressure internally and adding a second regulator can reduce performance. The Retro-Regulator is specifically designed for upgrading older, non-PRS spray bodies.
Is this a good alternative to replacing all my spray bodies?
Absolutely — that's the whole point. Replacing every spray body in an established system requires digging, pipe work, and significant labor cost. The Retro-Regulator delivers the same water-saving benefits as a PRS body upgrade at a fraction of the cost and in a fraction of the time. No plastic waste, no excavation, no hassle.
Before you install, verify the following:
Pair the H2OWize Retro-Regulator with these products for a fully efficient irrigation setup:
Mar 9th 2026
Mar 6th 2026
Mar 5th 2026
Mar 4th 2026
