The Senninger 1" Medium Flow Pressure Regulator is an essential component for protecting mid-sized agricultural setups, commercial landscapes, and large residential drip zones. Manufactured by Senninger—a global leader in irrigation pressure control—these heavy-duty regulators are engineered to safely drop high, fluctuating municipal or pump pressures down to a stable, reliable output. Supporting a versatile flow range between 2 and 20 Gallons Per Minute (GPM), they are perfectly designed for systems that fall right between standard residential and massive commercial flows. For ultimate protection, install this unit downstream of a 1" irrigation filter and your automated irrigation valves.
To seamlessly integrate into standard PVC manifolds, these medium-flow models feature 1" Female Pipe Threads (FPT) on both the inlet and outlet. They are available in three distinct, color-coded models to match your specific landscape needs. The PR1S12 drops incoming pressure down to a gentle 12 PSI, ideal for running thin-walled drip tape. The PR1S25 outputs 25 PSI, making it the industry standard for 1/2" poly tubing and emitter systems. Finally, the PR1S40 model outputs 40 PSI, perfect for running micro-sprinklers and dynamic spray zones without blowing out your fittings.
Detailed specifications for system planning.
| Specification | Details |
|---|---|
| Product Type | Medium Flow Pressure Regulator |
| Inlet / Outlet Size | 1" Female Pipe Thread (FPT) |
| Required Flow Range | 2 to 20 Gallons Per Minute (120 to 1,200 GPH) |
| Body Material | High-Impact Thermoplastic |
| Constant Pressure Rated | No (Must be installed after valves or timers) |
| Brand | Senninger |
| Part # | Regulated Output Pressure | Maximum Inlet Pressure | Flow Range |
|---|---|---|---|
| PR1S12 | 12 PSI | 90 PSI | 2 - 20 GPM |
| PR1S25 | 25 PSI | 105 PSI | 2 - 20 GPM |
| PR1S40 | 40 PSI | 120 PSI | 2 - 20 GPM |
Build your medium-flow drip irrigation head assembly safely.
Step 1: Prep the Threads
Because this unit utilizes standard Pipe Threads, you must apply 3 to 4 wraps of Teflon tape to the 1" male PVC fittings you will be threading into the regulator's inlet and outlet. Do not use liquid pipe dope.
Step 2: Connect the Inlet
Thread a 1" Male Pipe Thread (MPT) fitting from your upstream valve or filter into the 1" FPT inlet of the Senninger regulator. Crucial: Look closely at the body and ensure the directional flow arrow points downstream toward your fields.
Step 3: Connect the Outlet
Thread a 1" Male Pipe Thread (MPT) PVC fitting or tubing adapter into the 1" FPT outlet of the regulator to transition safely into your irrigation mainline.
Step 4: Pressurize and Test
Turn on the irrigation valve. The internal diaphragm will instantly drop the pressure passing through the unit, safeguarding your downstream drip lines or micro-sprinklers.
Which model do I need: the 12 PSI, 25 PSI, or 40 PSI?
Your choice depends entirely on the type of downstream tubing you are using. The PR1S12 (12 PSI) model is designed for very thin-walled Drip Tape (like 6 mil or 8 mil) which can rupture at higher pressures.
The PR1S25 (25 PSI) model is the industry standard for traditional 1/2" poly tubing and punch-in drip emitters. The PR1S40 (40 PSI) model is ideal for micro-sprinklers and dynamic sprayers that require more pressure to achieve their full spray radius.
What happens if my flow is less than 2 GPM?
Pressure regulators require a certain volume of water passing through them to accurately engage the internal diaphragm. If your zone draws less than 2 Gallons Per Minute (120 GPH), this medium-flow regulator will not function properly.
In low-flow scenarios, the pressure will not drop accurately, potentially allowing dangerously high pressure into your drip lines. For smaller flows, look for a Low Flow regulator.
Can I leave this regulator under constant pressure?
No, Senninger pressure regulators are not rated for constant pressure. They must be installed after an automated timer or irrigation valve so they only hold pressure when the system is actively watering.
Installing them upstream of a closed valve leaves the plastic housing pressurized 24/7, which can eventually cause it to stress, crack, or leak.
How should I winterize my Senninger pressure regulator?
Before freezing temperatures arrive, you must completely blow out or drain all water from your irrigation head assembly.
Any water left trapped inside the regulator's body will expand as it turns to ice, which will permanently destroy the internal diaphragm and crack the plastic housing. If you cannot blow out the lines, unthread the unit and store it indoors.
Please note the strict requirements for this medium-flow unit:
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