25 PSI Pressure Regulator


25 PSI Pressure Regulator

25 PSI Pressure Regulator

DIG’s 25 PSI preset pressure regulators (hose and pipe thread) are used to reduce and regulate the incoming pressure of a household’s water entering a drip irrigation or micro sprinkler system to the appropriate operating pressure of 25 PSI, which is within the range of recommended operating pressures for a micro irrigation system. The pressure regulators’ design includes few moving plastic parts and a diaphragm which regulates itself in reaction to the overall system back pressure. They offer exceptional pressure control and provide consistent outlet pressures over a wide range of incoming pressures.


  • Available with 3/4” female hose thread or pipe thread to fit all standard hose or pipe thread connections
  • Reduces incoming water pressure to the ideal working pressure for a drip system
  • High-strength ABS construction for durability
  • Compact construction of non-corrosive plastic materials
  • Low pressure loss and high flow rate
  • DIG’s drip irrigation products may be exempt from residential and commercial watering restrictions (check local codes)


How to Order
D46 25 PSI Preset Pressure Regulator Inlet 3/4 in. FHT x Outlet 3/4 in. MHT – (black)
D46P 25 PSI Preset Pressure Regulator Inlet 3/4 in. FNPT x Outlet 3/4 in. MNPT – (grey)


  • Operating pressure: up to 100 PSI
  • Flow rate: up to 10 GPM
  • Preset pressure: 25 PSI
  • Size:
    • Model D46 3/4” female hose thread x 3/4” male hose thread (FHT x MHT)
    • Model D46P 3/4” female pipe thread x 3/4” male pipe thread (FNPT x MNPT)
  • Color: black for hose thread and gray for pipe thread
  • Temperature range: up to 130°F
  • Materials:
    • Body: high impact plastic
  • DIG Drip Zone Head Assembly: Connecting to a Faucet


The pressure regulator is a critical part of drip and other irrigation systems when water pressure is higher than the suggested operation pressure recommended for the system. In most households the water pressure is between 40 and 100 PSI with some homes being even higher. Typically, in homes with high pressure, a heavy duty pressure regulator is installed on the main water supply to lower the pressure entering the house. Drip irrigation systems are designed to work at an even lower pressure than is set for the house, with the optimal pressure for a drip system being between 15 and 30 PSI. If a higher pressure is found in a drip system, problems such as drip emitters popping off the drip or micro tubing, high flow damaging the drip emitters or micro sprinklers, components blowing out of the drip and micro tubing, and overall shortening of system life can occur. To achieve extended life with high uniformity and lower maintenance, a pressure regulator is highly recommended to maintain optimum system pressure, regardless of any fluctuations in the house system pressure.

Installation suggestions

The starting point of connection to the water supply can be a faucet (hose bib), AC or anti-siphon valve, well, pump or rain barrel combined with gravity feed.

Installation into a faucet or to hose thread

To the faucet, first connect a backflow device (model D45). If water quality is a concern, install DIG’s fine mesh 3/4″ filter with 155-mesh (model D57A), then install the 25 PSI pressure regulator (model D46) and then a 3/4″ swivel adapter with screen (model C34).

  1. To automate the system, install one of DIG’s hose end timers before (upstream of) the backflow device.
  2. The 3/4″ FHT backflow preventer should only be used to keep contaminated water from re-entering the household/municipal water supply lines and in areas where discharge or spilling of water will not cause damage.
  3. The filter is used to protect the small orifices of the drip emitters and micro sprinklers against clogging and it is mounted after the backflow device if used.
  4. The pressure regulator should be installed after the filter if used, and only if the system water source pressure is above 30 PSI.

Installation into in-line valve or into pipe thread

  1. If installation is into a PVC pipe, first shut off the main water supply.
  2. We recommend installing a 3/4” ball valve or gate valve before the valve. This ball valve can be very useful as an emergency backup to turn the system off. This type of arrangement is used by professional installers.
  3. Turn the water supply on to flush the line and then shut the water supply off using the new ball valve or gate valve.
  4. Install the AC valve or battery operated controller, wrapping TEFLON tape on all the male thread fittings used.
  5. Turn the water supply on again to pressurize the system. The unit will open momentarily and then will shut off.
  6. To the outlet of the valve, install a 3/4” screen filter with 155-mesh (model D55) to protect the drip system from clogging. Then add the 25 PSI pressure regulator (model D46P) to lower the incoming system pressure to the suggested operating pressure of 25 PSI, which is within the range of recommended pressures for drip irrigation or micro sprinkler systems. Follow with a swivel adapter to the drip tubing or 3/4” PVC female threaded x slip adapter to the PVC pipe.
  7. Test the valve using the manual bleed. Check that the system is working and that there are no leaks.