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The Irritrol® 205 Series 1-inch plastic valve is the irrigation industry’s time-tested leader for dependable operation in potable and dirty water applications. With a proven track record of success in a wide range of environments, these debris-tolerant valves are available with flow control as an optional feature. Constructed of heavy-duty, corrosion- and UV-resistant PVC, the 205 Series features a high-flow, low-friction-loss-design that has a pressure range of 10-150 psi and flow range of .25-30 GPM. A manual bleed and a rugged, nylon-reinforced Buna-N diaphragm add to this valve’s wide popularity. Specs Flow Range .25-30 GPM Holding Current .2 amp Holding Volt-Amp 24 V ac-4.8 VA Inrush Current .4 amp Inrush Volt-Amp 24 V ac-9.6 VA Solenoid 24 V ac . Manufacturer's Web page: https://www.irritrol.com/en/valves/205-series
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Features
Features
Specs
Pressure regulation is not the same as Flow Control. The outcome can look nearly the same.
Our objective is to have consistent pressure at each head, and large droplets coming out of the heads, not a mist. Consistent pressure at each head is more of a function of system design / layout than pressure at the valve, but even pressure regulated sprinklers need an inlet pressure within a certain range. Sometimes large systems need high main line pressure to be able to deliver enough pressure at the farthest zones, so a Pressure Regulator at each valve helps us bring the pressure into our desired range for each zone. Keeping the pressure within the recommended range saves money and increases the efficiency of each irrigation zone. Sprinklers under excessive pressure will atomize the water or turn it into a mist. This means the water droplets are too small and more likely to be blown off course or evaporate before it can make it to the root zone. Notes: Inlet pressure should be at least 15 psi higher than your desired regulated pressure. When inlet pressure exceeds 100 psi, a pressure regulating master valve or inline pressure regulator is required. . Hunter model notes: Can also work with DC latching solenoid, Models can be adjustable or fixed pressures. Hunter's Accu-Sync is compatible with any Hunter valve. Rain Bird notes: Rain Bird valves have an adapter that needs to be removed before the PRS-D threads in. Valve models that are compatible are the PGA, PEB, PESB, EFB, & BPES. Toro notes: Toro has the EZReg that is specifically for the their P-150, P-220 valves.
Replace There are a few older valve models that don't warrant rebuilding. When you see these models, save your time and effort and immediately start working to cut out and replace. I won't give you a list of the models that we have problems with, as it may seem to be disparaging to those manufacturers, and mostly it's just old models that are out of production. Instead, if you're working as a technician, pay attention to the patterns and make your own list. There's no shame in cutting a valve out and replacing it with a new reliable model, instead of rebuilding the valve two or three times and still being unsure of it's reliability going forward. . Rebuild If you've gone through your troubleshooting sequence, and have determined that the solenoid is bad, just replace it. Turn off the main water supply first, though. Some valves are ok to replace the solenoid with pressure on them, and some are not. It's easy to cross-thread the solenoid when there's some pressure shooting out the small hole in the solenoid attachment pit. When you've worked through the troubleshooting methodology and determined that the diaphragm isn't working correctly, I recommend a total rebuild, meaning everything that can be removed off the lower valve body is removed and replaced. It's quite possible to just replace the problem component (usually the diaghragm) and return the valve to service, but years of experience has shown the error of that thinking. It's generally cheaper to buy an entire valve than to purchase the components separately, and with the cost of most valves being very reasonable, there's no reason not to replace everything. While you have the valve dug up and opened up, why not replace everything you can? If you're a contractor that warranties your work, you will be held responsible for the performance of that valve into the near future, so why risk a call back by not replacing all the components of the valve? . Water Leaking From Sprinkler This is an issue that we get calls for often. Your first question has to be, “Is it leaking all the time or just when the zone is running?” If the leak is only occurring while the head / zone is running, then a simple head replacement is called for. Water leaking constantly from a sprinkler normally indicates two things. The first is that the leaking head is the lowest in elevation on that zone, and the second is that it's the valve that's leaking, not the sprinkler. A valve will sometimes get a particle lodged between the diaphragm and it's seat, or the diaphragm itself will become damaged. A small amount of water leaking through will flow to the lowest head in the zone and start to dribble out. This is assuming that the head doesn't have a check valve. I've seen other contractors try to address the problem by putting a check valve on the lowest head. Guess what, the water just backs up to the next lowest head and leaks from it. I suppose that if all the heads had check valves, then possibly none of them would leak unless the pressure built up past the threshold limit (usually 8-10 psi.) Regardless, it's the valve that needs to be addressed not the heads, see “Single Valve Stuck On” step 3. . Single Zone Isn't Operating 1) First, ask enough questions of the homeowner or property manager. How long has this been going on? Has the system been used often or has it been off for the winter or possibly years? Has there been any construction or work of any kind happening on the property, especially cable / utility work? Has there been any new plants installed recently or new bed edges dug? Make sure the other zones are working and that water is flowing normally into the system. 2) Troubleshoot the timer settings first. Run through a quick check of ALL the settings, and make sure there's Run Time set for that zone. Turn the zone on. Walk the property and look for any leaks that may be occurring, look and listen! Give it a few minutes to see if any water comes to the surface, during this time, try to determine where the valve is, and walk the suspected pipe path between the water source and the valve, then out into the zone itself. 3) Go back to the timer. With the zone still on, use your multi-meter to measure the voltage on that circuit and then check the rest of the circuits. If you get voltage on any of the other circuits, there can be two problems happening. Either the timer has a problem or there's wires touching in the field or otherwise allowing voltage to be fed back through the other zone wires. To determine if it's the timer, mark the wiring diagram or take a picture of the terminal strip with your phone to make sure you put back all the wires correctly. Turn the timer to the OFF position, then remove all the wires. Manually run that zone again and recheck the voltage on that zone then all the others. If you're still getting voltage across more than one zone, you've got a bad timer. If not, there's wiring problems. The wiring bundle may have been cut through with a shovel and the wires are still close enough so that electricity is jumping the gap enough to be measured at the timer, or maybe a valve box is filled with water and all the wire connections are exposed or not protected by grease filled wire nuts. This can cause electricity to feed back along other wires. Assuming all the voltage checks are ok, now turn OFF the timer, insure that there's no current flowing, then check the resistance of the circuit with the Ohms setting on your multimeter. Also check the other zone circuits at this time to get an idea of what is normal from the other operational zone circuits. It helps to know what kind of valves you're dealing with so that you can know how many Ohms to expect from a healthy solenoid. Remember that the circuit will show the resistance of the solenoid plus the wire circuit plus one Ohm or two at most for the circuit inside the timer. If you get abnormal resistance readings, disconnect the wires for that circuit, check the resistance across the timer terminals, then measure the Ohms across the two disconnected wires. If the Ohms are too low, there's either a short in the wiring or in the solenoid. If the Ohms are too high but not infinite, it may be the solenoid going bad, or it might be a corroding wire splice at the solenoid or somewhere in between. If the Ohms are infinite (pegged out high) then the solenoid could be bad or the wire circuit is open somewhere, check the wire connections at the solenoid. 4) Reconnect all the wires if necessary then start that zone again with the timer. Now go to the valve. Do an eyeball check of the valve, is there a leak, was the valve installed correctly? If the valve or system was just installed, there may be some glue covering the pilot tube opening inside the valve under the solenoid. Try to actuate the valve by opening the bleed screw or by partially unscrewing the solenoid. If the valve won't come on, you've got a mechanical problem with the valve itself, probably the diaphragm. Rebuild the valve, or replace if necessary. If the valve did turn on when using the bleed screw, continue to check the solenoid. Are we receiving voltage to the solenoid? You can use the multi-meter to check the voltage at the wire splices. If unsure, turn the timer off then disconnect the wire splices. Restart the timer on that zone, go back to the valve location, and check the voltage at the disconnected zone wires. If that looks good, now we need to determine if the solenoid is operating properly. I recommend using a Station Master to apply voltage to the solenoid. If the solenoid doesn't actuate then replace the solenoid, wire it back up, and recheck operation from the timer. 5) If the valve was coming on when checking it manually, and the solenoid and electrical circuit checked out good, we've got a more complex problem. You should be able to hear or feel water passing through the valve if it's running normally. Recheck for a leak somewhere. Then, check for obstructions in the piping system. This is a factor that can't easily be tested for, it has be eliminated down to. If all the other possibilities have been eliminated, get out your garden hose. Unscrew a head and use an adapter to connect a garden hose. Turn on the water and back-pressure the zone. You may have to take off another head or disassemble the valve to be able to properly flush out the obstruction. . Single Zone Stuck On 1) Remember to ask questions; has there been any work done in the area? Has anyone else, such as a cable contractor, pool installer, or landscaper performed any repairs to the system? Look around yourself. Occasionally, when construction work has happened and pipes cut through, a zone pipe will accidently be plumbed directly into the main line. That's a pretty rare occurance, but it's happened a few times to my clients. 2) Check the timer first. Is the timer running? There may be errant settings that make it appear that the zone is stuck on, but it's actually the timer that's keeping the zone on. If the timer is running zone visibly, as in you can see on the screen the icon for system running and see time counting on that zone. Now get out your multi-meter and check to see if there's any voltage on that zone's terminals. It's possible that a circuit failure in the timer is causing the zone to run. 3) In the absence of timer or electrical issues, we know the problem is physical/mechanical. Address the valve. Take the valve apart and check the diaphragm for tears or a warped / distended appearance. Look inside the lower valve body, and stick a finger down into the hole to check for pebbles, debris, or even shards of broken PVC. You may need to turn the valve on for a couple seconds to fluch out anything in the pipes. Since you have the valve taken apart, I would go ahead and rebuild the valve if possible. If it's not a model that you would rebuild, then reassemble and see what happens. You may need to replace the valve. Single Zone Has Weak Pressure 1) Generally, this is caused by physical or mechanical issues. Always walk the yard to insure that you're not missing a pipe break or damaged head. Look closely, a missing sprinkler may not be shooting into the air, it may just be barely bubbling while it leaks a ton of water. Be sure to check around the entire property, there may be a sprinkler or drip line in a very improbable place that's attached to this zone. Check the water meter to see if it's turning slowly or as fast as a normally operating zone. 2) Check flow demand of the zone. Ask the customer if any recent repairs or additions have been made to the irrigation system, particularly the zone in question. It's possible that an additional sprinkler or two has been added to the zone, exceeding the flow / velocity limits of the zone piping. It's not uncommon to find that larger nozzles were put on to cover an expansion of flower beds or turf area. It's also possible that cable construction, landscape installation, or something similar has hit a pipe and crimped or crushed it without breaking the pipe. Like I said before, ask plenty of questions, and look for evidence of recent work on the property. 3) Locate the valve, troubleshoot the electrical side of operations, if not electrical, then disassemble and look for obstructions. Rebuild or replace the valve. 4) If the problem persists, remove a head and recheck pressure. It's possible that a zone line was broken by a cable contractor, or maybe even a main water line break upstream of the property, and rocks, dirt, or debris pushed into the irrigation system . If so, they normally accumulate at the barbed elbow or in the sprinkler head.
The Anti-Siphon valve is a combination product, Solenoid Valve plus Atmospheric Vacuum Breaker. An AVB is a backflow prevention product. and backflow prevention is an incredibly important aspect of irrigation systems. In the USA, it's mandated that every irrigation system have a device that prevents water that has entered the irrigation system from being sucked or pushed back into the drinking water supply pipes.
In some States, it's preferred to have a device at the beginning of the system, usually a double check valve assembly. Other States, however seem to prefer that backflow prevention happens at the valve. That's why the Anti-Siphon Valve is a popular product and used exclusively in some markets. Sometimes the product is misunderstood and installed in unapproved ways, or used on systems that already have backflow taken care of. Anti-Siphon Valves only protect against Back-Siphonage, which is suction or a vacuum in the supply pipe that would suck water backward from the irrigation system. That could potentially pull fertilizer, herbicides, or even dog feces (from a puddle of water around a sprinkler) into the main water
system. The ASV does not, however protect against Backpressure, which is water being pushed backward from the irrigation system into the supply system. For that reason, never Backpressure the zone pipes by attaching a garden hose or anything similar. Sometimes, when zone pipes get contaminated by a broken pipe, it's necessary to attach a garden hose to the furthest head, remove the closest head and push the contaminants out that way. Don't do it with an ASV, you could push dirt or rocks back into the main line. The Anti-Siphon Valve should be mounted at least 6” higher that the highest outlet or sprinkler on that zone. Never install an ASV underground, either in a valve box or direct buried. There should be no downstream shut-off valves.
Flow Control
A feature that was designed to help mitigate water hammer. By constricting the flexing of the diaphragm, the valve is made to open and close slower, which helps control the abrupt changes in velocity that cause the hammer or knocking in pipes. If the zone is under high pressure and misting at the sprinkler, the flow control can be used to get the water droplet size larger. A larger, heavier drop of water is more likely to land on target, rather than being easily blown away.
Pressure Control Some advanced valves have this feature built in, but other manufacturers offer this feature as an add-on part. The pressure is reduced without a subsequent reduction in flow. We feel that high pressure in a residential or light commercial system should be regulated at the beginning of a system with a pressure regulating valve, but larger systems sometimes have to be designed with higher pressures to accommodate longer mainline lengths, elevation changes, etc. This is when pressure regulation at the valve is crucial. Sprinkler heads operating at pressures higher than recommended will turn the water into a fine mist, which is easily blown away before it reaches it target. The goal is to have the water traveling through the air in a nice, fat droplet that's less likely to be blown off course. 
Angle Configuration
The in and out sockets are configured at a 90 degree angle. A straight configuration is also called a “Globe Valve” The angle configuration is typically used when the main line has to be quite deep and the valve needs to be located closer to the surface. Pressure loss inside the valve is slightly reduced in this configuration. Also consider that there is usually the elimination of one elbow, which also prevents more friction loss. Some 1.5” valves have a threaded plug on the bottom that converts a globe valve to an angle valve. . Atmospheric Vacuum Breaker The H configuration valve is a combination of valve and backflow prevention device. These are commonly referred to as “anti-siphon valves.” These valves should never be installed below ground level, in a box or not. They also should be at least 6” higher than the highest usage point (sprinkler head or drip line.) Check your local codes for details. . Brass Body Extremely durable models are made by most manufacturers. Plastic valves typically have pressure ratings around 150 PSI, but a brass body can handle up to 220 PSI. . Jar Top Configuration Several valve models also come with a bonnet that screws onto the valve body. Designed for ease of service, one can can take this valve apart without any tools for a quick flushing or diaphragm replacement. . Reclaimed Water Not only are some valve models designed for reclaimed, recycled, or “dirty” water, they also provide purple versions for easy identification. . Scrubber Valves These advanced features help keep the internal workings of a valve scrubbed clean of any contaminants. This is a feature generally found on more expensive valves designed for commercial or municipal use. . DC Latching Solenoids One can adapt a normal AC valve to work with DC battery powered timers by using a latching solenoid. A normal AC solenoid is held open by the timer during the entire run time of that zone. In contrast, a DC timer will send one signal which latches the solenoid open, then at the end of the zone's run time, another signal is sent to the solenoid which closes it.
There are several common issues with indexing valves that we're going to walk through. Since pump and indexing valve combinations are so widely used, I'm going to include some troubleshooting and repair steps that pertain to pumps. If you have a constant pressure municipal water supply, you may have some of the same issues with different steps to rectify. One of the most common issues is contamination in the water, such as sand or grit, and can be remedied by flushing out the valve. Taking off the cam and momentarily turning on the water to get a surge of water to flush out the valve is a great first step. Making sure the pressure and flow rate is ideal will also diagnose a lot of issues. Having a Hose Bibb on the supply line allows one to perform a 5 Gallon Bucket Test quickly or use a Combo Gauge to check pressure and flow. Supply pressure can be checked with a Pressure Gauge and should be between 25 – 75 psi in the case of the K-Rain Valve.
Low Pressure in Zone or Entire System
• Check the Case and Valve Top for leaks • Verify inlet pressure is within an acceptable range, usually 25 - 75 psi. • Check any Gate Valves or Ball Valves on the supply line and make sure there're fully open. • Check the Solenoid Valve if used for proper operation or blockages. . Skipping Zones • Make sure pressure and flow are within acceptable ranges • Check the Case and mechanisms for contaminants. Flush and insure that the Stem is bouncing freely on it's Spring. Clean or replace damaged componenets. • Insure that the water supply is steady. If a pump is used, check the pump for smooth consistent operation. A shallow well pump that's losing prime can cause an indexing valve to quickly advance though one or more zones, appearing to “skip” a zone. A vacuum gauge on the suction line of the pump can indicate leaks on the suction line or intake. A Check Valve on the suction line can also stop the problem by holding water in the body of the pump. • Check the Cam for damage and proper installation. . Low Pressure in Zone or Entire System • Check the Case and Valve Top for leaks • Verify inlet pressure is within an acceptable range, usually 25 - 75 psi. • Check any Gate Valves or Ball Valves on the supply line and make sure there're fully open. • Check the Solenoid Valve if used for proper operation or blockages. Skipping Zones • Make sure pressure and flow are within acceptable ranges • Check the Case and mechanisms for contaminants. Flush and insure that the Stem is bouncing freely on it's Spring. Clean or replace damaged componenets. • Insure that the water supply is steady. If a pump is used, check the pump for smooth consistent operation. A shallow well pump that's losing prime can cause an indexing valve to quickly advance though one or more zones, appearing to “skip” a zone. A vacuum gauge on the suction line of the pump can indicate leaks on the suction line or intake. A Check Valve on the suction line can also stop the problem by holding water in the body of the pump. • Check the Cam for damage and proper installation. . All Zones Running at Once • The Stem and Disc aren't seating correctly, remove Cam, flush and observe • Check inside the Case for any corrosion or scale buildup, particualrly on the lip that the Disc seats on, and the post that the Stem rests on. • Check the flow amount, using a 5 Gallon bucket test or Flow Gauge with a faucet on the supply line • Check zone pipes for a capped or pinched pipe. Back-pressure into the Valve could cause all the zones to to get pressure. For this reason, it's not sufficient to just cap off an unwanted zone. You should also get the proper Cam to match the number of operational zones. • Zones with too many sprinklers and too high of a flow demand can cause the Disc to not seat. Either shut off or nozzle down a few heads to check.
 K-Rain Indexing Valve Let's start this section by pointing out that every automatic valve has a specific direction of flow. Indexing Valves have an inlet port on the side that's pretty obvious, and zone or exit ports on the bottom. Check the instructions for a diagram of the ports to be sure. Solenoid Valves have direction-of-flow arrow printed or stamped somewhere on the body of the valve (the bottom piece which has the inlet and outlet ports.) The direction of flow can also be determined by the location of the solenoid, which is usually on the outlet side of the valve. Caveat: it's possible that there's some obscure valve out there that's constructed differently, but I've never seen one. Manual valves generally don't have a recommended direction of flow.  Hunter XC Master Valve terminal Master Valves The first decision to make about valves in the planning & design process is whether to use a Master Valve. A Master Valve is an additional solenoid valve that's located at the beginning of the irrigation main supply pipe. The main purpose of a Master Valve is to prevent catastrophic leaks and loss of water on the main pipe. The Master opens simultaneously with the zone valves, so it's closed during the time that the sprinkler system isn't operating. So the majority of the irrigation main isn't under constant pressure the majority of the time. During operation, the irrigation main will only be experiencing dynamic pressure, which should be less than static pressure. Most modern irrigation timers have the capability to run a Master Valve. There will be an extra wire terminal marked P (pump) or M/P (master valve or pump.) don't worry if it's a P terminal, the timer will be able to power either a Master Valve or a Pump Start Relay. The timer will have an output capacity of around 1,000 mA. Most irrigation valves require 350 – 450 mA inrush current to open, so 1,000 mA will be more than enough. Check the timer's manual or look on the wall-wart transformer to be sure.
It's usually best to cut the outlet side pipes for a replacement, and a union is great to install on the outlet side when using threaded valves. It should be noted that manifold configurations usually use more pipe to get from the centralized location to each zone, but less wire. Bundled irrigation wires are acceptable to use, if the distance from the timer is within the specs for the smaller wire. A satellite configuration is where each zone valve is placed in the vicinity of the zone that it's supplying. This config uses less pipe but more wire. Larger single strand irrigation wire is typically used since longer wire runs are involved. Also, the irrigation main supply pipe will be longer for a satellite config. Larger properties and commercial installations usually satellite the valves. Each valve can be placed in a 7” or 10” round valve box, although I've seen two valves in a 10” round box (kinda tight in there.) Order of Components The order of components on the irrigation main is: supply point > backflow preventer > pressure reducing valve > master valve > zone valves. The pressure reducing valve is an optional piece that may be necessary if the supply pressure is too high. The master valve is optional as well, a safety feature to prevent loss of water from a main line leak. The other variation is when using Anti-Siphon Valves. These valves are a combination of solenoid valve and backflow preventer, so a central backflow preventer at the beginning of the system isn't necessary. Check your local codes, some cities or states prefer ASVs over Double Check Valve type backflow preventers.  Many water systems maintain a very high pressure in their main lines which can be up to 200 psi. This pressure is necessary for water towers, fire fighting, elevation increases in the topographical layout of their service area, or even for elevation increases in tall buildings. Once that water enters a home's plumbing or irrigation system, it needs to be reduced to a manageable level. Many plumbing codes specify use of pressure reducing valves for pressures over 80 psi, and that's a great guideline for irrigation as well. Even though the pipe and fittings are generally rated for 150 psi, this high pressure can wear out components such as valve diaphragms and o-rings, cause pinhole leaks in improperly cured solvent welds, and cause water hammer. It also uses more electricity to open the solenoids, although that's not a huge consideration. More importantly for the financial and ecological bottom line, high pressures cause loss and inefficiency through misting at the sprinkler heads. It should be noted that pressure reduction is not the same as flow reduction. Partially closing a ball or gate valve reduces the flow, not the pressure. A spring loaded diaphragm mechanism is needed to control the pressure and attempt to mitigate any pressure fluctuations from the source. . Adjusting a pressure reducing valve can be a little counter-intuitive. A downstream pressure gauge is needed to monitor your adjustments. First, loosen the locknut and rotate it to give the main pressure adjusting screw room to move. One would think that the principle of “righty – tighty” would apply here, but actually a clockwise rotation raises the downstream pressure. Rotating the adjusting screw counter-clockwise results in a reduction of the downstream pressure. Once you achieve the desired pressure, re-tighten the locknut.
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