Most homes and businesses have water pressures that range from 30 psi to 50 psi on average, and the majority of sprinkler systems are made to work with pressures of approximately 30 psi. A flow meter or water gauge fitted to an outside faucet will allow you to monitor the water pressure at your location.
Sprinkler heads are rated at a specific GPM flow rate at a specific pressure. We recommend that you use 40 psi when designing your system.
Class 200 pipe, the most common class pipe used in irrigation, is rated for 200 pounds per square inch pressure (psi) and has a wall thickness of . 063” for a 1” pipe.
Pressures higher than 80 psi can possibly damage household appliances. Generally, the ideal pressure is 65 psi. A pressure regulating valve (PRV) can be used to reduce if the pressure is higher than 65 psi.
For spray heads, it is 30 psi, with an operating range of 15 to 30 psi. For drip lines, this is about 20 psi, with an operating range of 15 to 30 psi. Remember, flow rate and pressure are directly related to one another. If pressure is not well-controlled, irrigation efficiency will suffer.
The average water pressure for most homes and businesses is between 30 psi and 50 psi; most sprinkler systems are designed to use pressures of around 30 psi.
Fire protection piping systems are pressure tested to reveal any leaks by pressurizing the piping to 200 psi for 2 hours. 2.
Normal sprinklers are rated for 175 psi. High pressure sprinklers are rated for 250 Globe HP ARE 300 psi. There may be others that go 300, but they are costly.
High water pressure can be caused by high supply pressure or changes in landscape elevation. High pressure can be managed by installing pressure regulators on the main line near valves that separate irrigation zones or sprinkler bodies that have internal pressure regulation.
You need pressure regulators to achieve the intended distribution pattern and application rate. If you do not control the system pressure, it can negatively affect the sprinkler performance. Without regulators, the throw radius can alter, fitting, and emitters could even take damage or blow out of the tubing.
In general, residential water pressure ranges between 45-80 psi (pounds per square inch). If your water pressure is under 40 psi, it's considered low.
The number of sprinkler heads per zone depends on the water pressure and flow rate of a system's water source. A traditional system may have a dozen rotors and 8 to 10 spray heads. An Irrigreen system only needs one sprinkler head per zone.
Most automatic sprinkler system components are rated for a maximum pressure of 175 psi, especially sprinklers. NFPA 14 requires standpipe systems to be limited to a maximum working pressure of 400 psi and express mains are permitted to have pressures more than 400 psi.
The number of sprinkler heads you can run on one line depends on your system's water pressure (PSI) and flow rate (GPM). For instance, if each sprinkler head requires a flow rate of 1.31 GPM and you have a total system capacity of 16.67 GPM, you can run about 12 heads on one line.
By checking the pressure regulator, inspecting the sprinkler heads, checking for leaks, doing a pressure test, installing more stations and increasing the water supply line, you can boost water pressure and keep your lawn healthy and green.
Average Water Pressure For A Sprinkler System
Water pressure is measured in pounds per square inch. For residential and small business applications manufacturers recommend 30psi at the head for sprays and 45 psi at the head for rotors. Larger heads will require higher pressure.
To find leaks, a low pressure (30-50 PSI) air test is just as effective as high pressure (150 PSI) water test. This is because the viscosity and surface tension of water is greater than that of air.
If it is proposed to fit a sprinkler which is supplied directly off the mains, please note, that the pressure in the water mains network varies between areas and throughout the day. Normally it is in the range 2 Bar - 3 Bar, with a minimum of approx. 1.5 Bar.
Checking sprinkler water pressure is quite simple. Attach a pressure gauge to an outside hose spigot to check source pressure. To check sprinkler head pressure, insert the end of a pitot tube into the stream of water coming from a nozzle. How your sprinkler system runs is highly dependent upon water pressure.
All new or modified sprinkler installations, where the system working pressure* allows, should undergo a hydrostatic pressure test of no less than 200 psi [14 bar] for 2 hours with zero loss in pressure at the reference gauge or visual observation of a leak.
Most automatic sprinkler systems require between 40 to 60 PSI to operate properly. Because water pressure fluctuates throughout the day, it's best to make sure other faucets in your house are off and that you record your water pressure at around the time you will likely be using your irrigation system.
Answer: The pressure requirement varies from 2.0 to 4.0 kg cm-2 with application rate from 4.0 to 20.0 mm hr-1 depending on the nozzle size, spacing etc. Fig. 36.1.