Controlling Plumbing Pressure with Direct Acting Pressure Reducing Valves

the broadcast is now starting all attendees are in listen-only mode hello welcome coffee with Kalani here we are a beautiful fall day in the Ozark I hope you're enjoying the same weather today Kevin's with us Kevin Freitas our product men are dropping clumping Milwaukee and he's put together great presentation they're gonna like this one on pressure reducing valves hopefully everybody knows that Club he is offering pressure reducing valves now so we wanted to give you the lowdown how they work the difference and all that so there's a lot of great information in this slide so latest issue I'd raunak's number 21 you should have that by now if you don't let us know make sure that you're still on the list of that but that was mailed out and that we don't really have an ID Roenick specific to the topic today we just want to make you aware that you know we have them coming out and make sure that you're getting those and let us know what you think of that and what else we can use for topics if you have anything in mind we're always anxious to hear that I think Kevin there isn't anything else I think that's that's about it thanks Bob hello everybody today's topics let's go through those real quick so we know what we're going to talk about first of all what is a PR meet we will talk about how a direct acting PR B works and a pilot-operated PR B will discuss selecting the right PR me for your application how to size it will discuss in detail fall off pressure that seems to be a topic that people are curious about another question that came in was in regards to domestic hot water expansion tanks so we're going to talk about those when they're used with PR B's we'll get into a little bit of math and look at head pressure and PR B's and multi-zone high-rise applications we'll talk about piping theories and parallel yes you can do that and we'll just discuss that also in series so great topics we'll talk about failures what are the things to watch for what are the concerns and talk about maintenance too and lastly we'll talk about the kalevi 535 PR be got got a lot of great features and benefits to cover there so and then stay till the end we want to make sure that you're there so you can vote for the klephts the excellence winner near the end of the presentation so those are the topics let's go jump right into it first of all I want to thank everybody for submitting your pre webinar questions we got a bunch of great questions that came in and I hope I address most of your questions in this presentation if not they'll be sure that you know we will send you an email reply and that that also is applicable to any questions you send in while we're talking you can see down below that you can put comments and so I encourage you to do that and we will respond to all of them let's take a look at this nice graphic that illustrates how the Great Lakes Water Authority a distribution system works I like this because it shows a big picture all the way from supply to the property donor so of course here we have the water intake this is actually a lot like the the facility just north of Milwaukee off of Lake Michigan so we bring the water in it goes through a water treatment plant and perhaps they use ozone or chlorine treatment of some sort and then send that water out where we may or may not have a reservoir and the booster stationed in the system like this on to master meter and then the transmission line of course continues on down at some point we would come off the transmission line to distribution mains and we're showing right here at PRV and that large pipe and here's an image of a flat user PRB this is actually a color feed product and the PRB will reduce and stabilize that main supply water pressure to a usable level so why do we need to do that well main supplies can be very high in pressure and too variable for the end user or the customer so that's that's really the base purpose of the PRV so as we come down the line here we come over to water mains where you'll see fire hydrants and service lines and curb stop valves eventually to the property owner or the end user so here's where we would find pRb like the one I show here there might or may or may not be a water meter there and there may or may not be a backflow preventor at that location so at that point let's take closer look at that that property owner or the service line end of things here's a schematic of a typical domestic water system for a residential customer and you can see this first item here this is a backflow preventor and we're not going to get into too much detail here that's a future coffee with Cola fee but in this schematic we come through a backflow preventor to the PRV and then on into the the customers facility where of course that cold water is is piped up to the various fixtures and also it goes over to the domestic hot water supply where in this schematic we're showing a relief valve on the tank and this hot water supply comes out this this graphic has a thermostatic mixing valve course then that serves tempered water out to the facility now some homes like mine I don't have a PR B because the municipal water supply is is at the right pressure to serve the neighborhood where I live so you may or may not have one of those now commercial application is the same really just larger more piping more building more pee RVs probably especially if we're looking at multiple floors so that's just really general we want to do now is shift gears and let's look at how a p RV works okay this is a basic graphic that shows that appear RV uses what's called a force balance principle so the outlet pressure on the bottom of the diaphragm this light blue area here opposes the spring pressure on the top of the diaphragm to control the position of what we call the poppet down here or the valve and the valve seat and if the force on the top of the diaphragm is greater than the force underneath the diaphragm this poppet will be open which allows more flow and more pressure so the stem in other words is pushing downward in this case the more pressure and more flow would be passing from the the inlet of the valve to the outlet of the valve vice versa if the force on the bottom is greater than on the top and this puppet is pulled closed in the stem moves upward so the pressure adjustment up here will increase and decrease this upper force on the top of the diaphragm so when the outlet pressure is equal to the force on the top of the diaphragm then we have a stable condition here if the outlet pressure drops let's say that you have some fixtures that open and this outlet pressure decreases what happens okay this diaphragm will move down and open the poppet to bring more flow and pressure out does that make sense all right there a couple of pictures this is a one-inch valve in a residential application you can see this looks like this was just recently put in it's a lot newer than the existing piping so this is a small PRV that probably has an inlet of maybe 70 psi from the supply and maybe a 45 psi setpoint a lot of valves come out of the box set at 45 for residential applications here's a larger one this is a one in a quarter-inch valve that's installed in a small commercial application and this one is in a building in Milwaukee and the inlet here because the water pressure varies so much where we are you need a PR B to stabilize and control that pressure and this one happens to be set at 75 psi which is which is a typical setpoint for a commercial building that has a lot of piping evanescent burst pictures of clothes for example why you need a backflow preventor because you can see there's a hose pipe connection right next to that and if there was a low-pressure condition on the main it's possible to suck water either from the landscaping connection there to the right or from that hose bib so hopefully that City protects it out at their meter pit or something yeah obviously that's not up in northern climates by the plant material there and being outside that's probably in Southern California or Florida so this is a really neat picture that we got from a Brazilian colleague you notice that the plastic pipe according to our colleague in Brazil these are parallel redundant PRBS these are collector they're sold in South America and in this case for them it was a requirement by code so here you can see the isolation valves which are obviously a really good idea because for redundant service you need to be able to clean out these Weiss trainers so this is great because they can just valve off one line or the other or clean a strainer and not have to shut down the system to keep moving another slide showing a direct acting PRV up here in the top if you can see that that's a direct acting PRV and what we have going on here is the water is coming through a testable backflow preventor you can see the discharge piping there on through a water meter so in this facility up and British Columbia they are measuring the water consumption probably for conservation purposes and then the water comes up and there's the parakeet now there's a bypass around the PRV that's not uncommon actually in some places that's actually met and dated by code so we like this picture too thanks to Rocky Point engineering for that okay what about a pilot operated PRV okay I drew the pilot in red here and you can see a pilot operated PRV basically has a miniature PRV in between the inlet and the outlet of the valve so there's a connection to the inlet from this pilot there's a connection to the top side of the diaphragm and there's also a connection to the outlet its function is to provide additional control to the main part of a PRV and what it does is it improves response time and accuracy and these are typically used on larger valves because of the physical size and the internal components of larger valves can be slower to react to downstream dynamic pressure changes so typically they are larger bouts maybe two and a half inch on up and typically flanged whereas smaller sized valves quick to respond because they have less area and so typically a pilot is not necessary here's a picture of a clevy flanged cast iron pilot now look at this here you can see this connect here's the pilot right this connection is on this side of the PRB back here is a pipe that connects to the other side of the PRB and this tube right here is the one I talked about the connects to the top side of the diaphragm so this product is sold in Europe today we don't currently offer this in the US but I think it's a great example of a pilot alright let's talk about selecting the right PRV for your application first and foremost we need to make sure that we know the main supply pressure that the valve is going to be looking at we need to make sure and select a valve that can easily handle that inlet supply pressure need to make sure we know the maximum and the minimum outlet pressure requirements so this is the pressure that is going to supply the fixtures in the building such as you know the toilet some showers etc so on the outlet we will have a maximum allowable pressure and actually by code the UPC says 80 psi is maximum so that that's going to be a governing value and also a minimum usable pressure what what is that for okay fixtures require a certain minimum pressure to function properly so we need to make sure that the valve can deliver at least that minimum pressure out to the fixtures okay flow rate we need to know the maximum flow rate and the way we do this is it's a fixture calculation procedure that I'm going to describe in the next slide and this is part of the design to determine the maximum flow and the minimum flow rate why do we need to know and and pay attention to the minimum flow rate well we don't need to specify a valve that is is too big an oversize PRV is going to be on stable if you're trying to operate it near the close position as with any control valve and if you try to operate a valve near closed for too long you'll see problems for example premature wear on the seat and Kalihi has has a guideline here that we want to also suggest a three-to-one ratio between Inlet and outlet of a PRV now let's talk about that a little bit this is a conservative guideline so you don't want to use one PRV to try and reduce from extremely high pressure down to a low pressure we're going to talk about that a little bit more later in the slide but this is an important factor when you're sizing your PRV because you do not want to risk seeing cavitation cavitation is is the formation of vapor bubbles which will occur when a liquid is subjected to a rapid reduction in pressure a high flow rate through a small restriction will cause a severe pressure drop enough in fact to cause that vapor formation okay and when when the pressure recovers just downstream of the restriction those bubbles will implode and can generate really intense shock waves and cause a lot of damage to the piping and the valve and sometimes it can sound like gravel flowing through the pipe and definitely not a good thing here's a spec for the Colet 535 for example so in our literature you'll see that we have the maximum pressure rating the the pressure setting range the the factory setting which is just what the knob is set at when it comes out of the box and a maximum working temperature of 180 Fahrenheit which is a really nice high temperature rating I'm going to get into some details later about hot water booster systems and that becomes important okay regarding design flow rates designers will use tables such as this now this is just an example of a table this particular one you can find tables like this in the in the UPC the plumbing code even vendor literature for example and what this is is it's showing different types of fixtures in either public or private applications and what it has over here on the right or fix your units now a fixture unit is not a flow rate but it's a design factor that takes into account the likelihood that all of the fixtures in a given circuit are not going to be used at the same time so a good term for this is maximum probable demand that's understandable we understand what that means and so what you do is you look at which type of fixtures you have how many and what you do is your total up all of these numbers you know the for example five fixture units for one water closet that uses a flush tank if you had ten of those that would be 50 total fixture units for example now what you what you need to do with that is convert fixture units to GPM right so the one way to do that this is a chart from the ASHRAE handbook I believe this one is called the the modified Hunters curved method and once you sum up your fixture units say for example you came up with a hundred fixture units in the table we looked at just just before what you can do is start from here come up and reach the line that corresponds to the type of facility you're looking at be it a hospital or a school or a restaurant and then come across to the GPM and those those values will represent your maximum probable demand that the PRV has to serve okay by the way I invite any comments about this from any of you engineers out there if you use certain approaches or practices or more methods we'd love to hear from you so once we know the flow rate demand we need to select a PR V so if you're selecting a khalifa PR we we have this chart in our technical brochure and because now we know the GPM that's what's down here on on the X on the X scale okay this chart comes from our 535 brochure and the process to select the valve size once we have the GPM is really easy I want to point out this blue band right here Coletti recommends for sizing for your maximum probable demand to stay in the range of three to six feet per second so this is the sweet spot for determining valve size based on your maximum probable demand let's take for example if we had a requirement of eight GPM as a maximum product demand excuse me maximum demand for a water come up from eight GPM you can see right here the three-quarter inch valve is perfect that one's right in the middle of the blue band so a three quarter inch valve would serve a TPM and you'd be looking at right around four feet per second in velocity so that'd be just right now you don't want to undersized the valve and and have too much pressure drop if you're trying to deliver excessive gPMs and and you don't want to oversized a valve as I mentioned earlier one feet per second one foot per second is the recommended minimum flow in the Colet 535 h4 stable control so for example this three quarter inch valve can easily control down to right around two GPM on up to what's that about twelve and a half GPM at six feet per second so this is the range of the valve for GPM now that we have the the GPM and we've selected the valve here's that eight GPM again come up to our three quarter inch valve this is graph number two where we determined fall off pressure now fall off pressure is for this F for this particular example right maybe 7.1 psi okay the fall-off is really the pressure drop across a PRV at the design flow rate compared to the setting on the knob okay and why is that important what we need to do is make sure that the fall-off pressure plus all the piping losses from the valve down to the fixtures does not reduce that supply pressure to a value that's less than the fixture is going to require for proper operation so it's an important concept and let's take that a little further and look at some actual lab data that came from our test lab here in Milwaukee this line represents a test that we did on three-quarter inch Colletti PRV with a 90 psi supply and a set point on the knob of 75 psi which is pretty typical for a commercial application so this particular test was was emulating a commercial application so we start at 75 right here and the laws of fluid dynamics are saying that anytime there's flow through a restriction you'll have a pressure loss so you can see what happens here as we start to flow water through that valve the pressure drops continues to drop so the outlet pressure over here say we start at 75 and assume we have one faucet running okay that's maybe a one-and-a-half GPM faucet what happens to the pressure of the valve it starts it 75 and drops yeah maybe to 73 so you can see there's a little bit of a pressure drop there two faucets okay so double that out to three GPM okay the pressure falls a little more now we're maybe at 71 psi so that would be a fall-off of 4 psi still not not really a problem we're still probably going to be able to serve everything we need to downstream of the valve okay let's say we have three showers running and showers are 2.5 GPA mhm okay where are we now we're down to about 68 which is a fall-off of seven psi so this is probably still going to be okay but what we need to remember is it depends on the pressure losses and all that downstream piping and the flow and pressure requirements out of the fixtures and also looking at this graph you can see we took it all the way out to probably about 48 so eventually you get out here to a point where you've really dropped a lot and it's not unusual to see a 15 or 20 psi fall-off pressure and a PRV application so let's say we had 20 here we'd be at 55 and where would we be on the flow curve so maybe about 21 GPM at a fall-off of 20 psi okay and that makes sense so here's another graph of that same test what we did is we took five different brands of pee RVs and put them in in the same test you can see some of these valves after about five GPM or after we've dropped six or seven psi fall-off they really start to change and some of these fall off rather rapidly so what does that mean okay a valve with with rapid fall-off will deliver a lower pressure out of the fixtures than a valve would that has a better fall-off performance so let's switch gears again a little bit and let's look at a schematic and get a little better understanding of what this means when they're talking about a system okay in a residential system really fall-off is not a significant issue why because it's a smaller system you know you may only have two or three levels and relatively short piping runs so let's take a look at this here for a minute here we're coming in with the supply again why strainer highly recommended in some cases mandated we go through the PRV and in this particular schematic we have a check valve so again we come out and serve the fixtures and as we come over here to the hot water store we want to talk about this we've had a question or two come in on expansion tanks when do you need a domestic hot water expansion tank well the uniform plumbing code says you need one unless the system is designed by a professional engineer so I guess there are other ways around that if a PE is designing the system too if you have a hot water storage tank what you'll see is expanding and contracting water in some areas if you have a hot water storage tank the expansion tank is mandated now you may not need one for an on-demand water heater why because you don't have a large volume of water to expand so for example if this was a 50 gallon storage tank full of cold water and you heated that up to supply temperature you might be looking at 52 gallons of volume so what does that do it puts stress on on all the rest of the piping if you don't have an expansion tank also if you have a backflow pressure a BFP installed in the system the UPC says you have to have an expansion tank so before the days when backflow preventers and check valves were really widely used and and mandated by code in some places some pee RVs had a built in bypass feature which would allow the water to actually return to the supply side generally that's not acceptable today having any idea if you're on a well system where you have obviously a pressure tank and if it's required on that I've never really seen an exception for that but it wouldn't seem like you would need one on a system that has your you know Nolan private well unless there's a check valve between the the tank and the water heater somewhere yeah great question now you know I'm not sure of that answer but if anybody out there knows that answer we'd love to hear from you I don't know if if there's a code that addresses that any other comments about this one Bob but mark back in that question I think because you are controlling pressure by way of your pressure switch and your holding tank with an expandable diaphragm I can't imagine a typical situation where you would also need to have a pressure PRV okay yes as far as fall off pressure we kind of led into this slide with fall-off pressure for residential buildings not really a major concern okay it is a factor in commercial applications okay here's a schematic that illustrates that when we have multiple levels or multiple branches and long piping runs fall off pressure is a significant part of the design process so very important okay all right we're going to do now is talk about multi-story commercial buildings but before we do we need to understand head pressure so we'll then do a little bit of math here stay with me on this but let's start with the basics if we have a vertical pipe containing one foot of water the pressure at the bottom of that pipe is going to be point four three three psi okay it doesn't matter if you have a one inch copper pipe with a foot of water in it or if you have a storage tank with one foot of water in it because we're talking about one square inch at the bottom of that column so one foot equals point four three three psi all right but what does that mean when when you're talking about floors in a building let's take for example a five-story building that's 60 feet from floor one to floor five for example so 60 feet times 0.4 33 is 25 psi so we would have static head pressure in that column of water of 25 psi measured at the bottom so that means if we have five floors let's just assume that they're all the same and one floor is 12 feet which equals five psi so where am I going with that okay now remember we talked about minimum supply pressure for fixtures we're going to select a number of 35 let's say that the fixtures we have in this application I'll require a minimum of 35 psi and you'll see where I'm going with this in just a second and remember we talked about the UPC code saying that 80 psi as a maximum for anywhere in the system to protect the fixtures okay so if we're pumping from the bottom or if we're pumping or if we have a PRV down on floor one we need to have at least 35 psi up at the top at the end of the line so as we work our way down the column remember 5 psi per floor right so we've got 40 45 50 and 55 psi so this is where static head pressure comes comes into you know consideration when you're talking about multi level buildings what if we have a 30 floor building all right let's say that we're still pumping from the bottom now in talking to a couple of plumbing engineers and again if anybody else has a comment please send it in that it's pretty common to have every five floors of PRV I've heard that from a couple of different sources so I'm going to use that in this example and now maybe it maybe more maybe less it depends on the piping there are a lot of variables involved but but let's go with that for now we talked about 35 psi minimum 80 psi max okay so let's start at the top since we're feeding from the bottom what are we going to have on floor 26 55 psi right 35 40 45 50 55 it adds up as we come down 60 on floor 25 80 on floor 21 okay on down the line this is building up static head pressure all the way down through that column of water and what do we have at the bottom 180 psi now this is just static pressure that we're looking at here all right anything jumping out at you here if we had to supply that water from floor one that pump or that PRV would have to be producing 180 psi to lift that water all the way up to that there a floor and have 35 psi but remember 80 psi max in any group of circuits so starting from the top you come down look what we've got at floor 20 it's a problem in floor 16 so what we have to do is put a PR V there so we're going to change that 105 psi down to 80 for example 80 might might not be 80 you might set it at 75 okay on down the line we have to put a PR V here to change 130 and reduce that down to 80 155 done in floor 6 we've got to put a PR v there and we have to have a PR be down at the bottom okay now this is just one example I want to make sure that we're clear here that you can put P RVs on every floor you can use multiple booster pumps there are a number of ways to do this what we're trying to do here is just discuss the principles behind using PR B's and how they relate to static head pressure so yeah you can source it from the top also here's a picture of a couple of water tanks in New York City up on the roof there are actually tens of thousands of these in New York City which is really cool and they're still widely used so the principle here is sourcing from the top the same principles apply right we still have that static head pressure build up from floor 30 down to floor 1 and for hot water as well of course you know that it's the same principles right now one thing to watch out for with with hot water is if you're looking at a project like this that's 30 floors and you have hot water you need to make sure that those prvs are designed for the hot water temperatures that you're going to be producing in that building for example the the kalevi 535 H is rated for 180 degrees Fahrenheit with NSF 61 so NSF 61 has three levels they have cold domestic hot and commercial hot and our valve is rated for that commercial hot temperature so 180 not all valves are so just wanted to to make sure that you know that okay be armies in parallel this is a great question that came in yes PR bees are often and it's very very common to see armies in parallel in commercial applications so why do we need to do that why not just put a single large valve in that will meet the high flow demand so let's take an example here say we have a requirement in a group of fixtures that needs to be from three GPM 230 GPM okay looking at a three quarter inch valve this is our five thirty five if you remember I mentioned that the range on that is from 2.1 GPM to 12 and 1/2 GPM so one foot per second to six feet per second that'll handle the low end right that valve will handle the three GPM perfectly but it can't get up to 30 so our inch and a quarter valve with a 5.3 to 34 GPM range that can handle the high end remember we talked about using a single large valve controlling it very low flows that's not advisable so what do you do you pipe them in parallel and here's a picture again I'm showing the isolation valves because that's just best practice right so what we do in this case is we set the small valve to our required setpoint let's just say for example we want our supply pressure to be 70 psi where this valve is located all right so what happens here is that that small valve will handle flow from 3 GPM right on up to about 12 and 1/2 GPM so what happens if you remember fall off pressure when the flow through that three quarter inch valve reaches a certain point and we have sufficient fall off pressure for example 10 psi so if that small valve was looking at a fall off pressure of 10 then you set the big valve to 60 and what happens is then they sequence and that large valve will open once that fall off or downstream pressure reaches 60 here's a great picture of prefabricated this one happens to be pilot operated large valve okay and a direct acting smaller valve and you can see there how that's pipe dense it's a nice shot that we took at a local hospital what about P RVs in series we mentioned that - yes it's very very common to pipe them in series series four to stage pressure reduction so when do we need to do this well if the amount of pressure reduction is is too much for just one valve then we need to put two valves in series now guidelines again khalessi says two to one is ideal you shouldn't have any problems reducing from a two - you know a two to one ratio from Inlet to outlet and we have a sort of a soft guideline of saying okay up to three to one is fine you may or may not be able to go higher than that maybe even up to four to one but the the the consideration is when you get up into those high ratios you're looking at possible cavitation and noise and erosion so just just beware of that for example if you do this if you if you try to reduce 200 psi to 45 psi no matter whose valve you have you're probably going to be looking at problems and we've heard recordings of bouts literally screaming I mean just a really high pitch you know break glass kind of pitch you don't you don't want that so what you do is put two in series just like this picture bring 200 down to 100 and then bring that down to whatever 45 for example let's look at Peter there are the failures or poor problems okay the number one that according to what we see is dirt dirt and clogging this is an actual valve that came back one of our valves that came back from an installation in the northeast part of the States and the complaint was that it wasn't holding pressure it was allowing the downstream pressure to creep up so we got this valve back and we opened it up and lo and behold the screen is full of nasty dirt this is a real problem the screen caught most of it obviously but look look at the seat inside of here you can see there are deposits around the seat now this is where the valve seals so because there are little particulates and impurities down here sure that pressure is going to leak through there so so dirt is a major factor that's why you want to put isolation valves in have a regular maintenance program for any kind of PRV they that you have to high velocity mark did you have something I was going to make a comment and and that is that I think all pressure reducing valve manufacturers will offer some sort of stream screen in there a PRV to protect against just what you are showing there and and so some some of the plumbers will practice redundancy and include some type of straining device up string from the PRB to give that double layer of having a chance of catching the debris before it has a chance to get into the seat yeah that's right and even in some codes mark I've seen that if the valve is smaller than an inch and a half you have to have a pre-filter so depends on your your region and the codes in your area of course now velocity high velocity is a problem we've touched on that a little bit if you have too much velocity too much pressure reduction in a valve what you have is again the possibility of noise erosion vibration and and that's that's also a problem Kevin can I say one more thing too on those screens yes green plugs up like that obviously you're going to get less flow through that valve so you think your valve maybe is undersized and you get a lot of pressure drop but it could in fact be at them help not the sizing of the valve because that strainer obviously just like a why strainer when it's 75% clogged you've got quite a bit of pressure drop through it so it's that uneven with isolation valves on both sides of the valves this is a this is a maintenance item on any system that you need to be able to get in there and clean that out from time to time so isolation on both sides interacted in fact Bob what you'll find sometimes with this debris situation is because of the Bri will get caught in that steep what you'll see in your building is when there's no demand a slow increase in your system pressure and and you would think that a higher pressure in your system would lead to higher air flow but when as soon as there is a demand because of that clogging you get less you get more fall-off and therefore less flow at your fixtures so you're seeing high pressure on your system side but when there's a demand low flow and that's a common symptom of you have a debris situation and what we did is we cleaned this screen we cleaned that seat and put it in a lab and tested just fine so nothing wrong with the valve it was just dirty that's plenty of life diaphragm failure now this is another problem that you'll see out there it's a catastrophic failure of the PRV and i think mostly this would be a result of chemicals in the water maybe chloramines and the wrong kind of EPDM or the type of rubber diaphragm just just failed due to just just due to becoming weak in a pilot operated pRb the block pilot is the major concern remember we talked about that pilot it has small pipes small cavities it's a mini PRV and the larger the PRV the more maintenance you have and on a pilot operated one almost all the problems are coming in in the area of the pilot getting clogged up now another point to regarding causes of failures it's very important to have hammer ear esters installed in the system at locations that have solenoid operations like dishwashers with that if you don't have that you can get your hammer which you know is hard on the diaphragm it just just exercises the diaphragm or the necessary it could reduce the life so amaura arrest rates or surge arresters now so in summary you know a good inspection regular maintenance program is highly recommended and yes PR B's you don't want one to fail because you're gonna have significant downtime so redundancy like that picture in Brazil or you know isolation valves like Bob mentioned are important so right now what I want to do is throw out a poll question we want to hear from you on what you see as the main causes for PRV either replacement or failures you know is it is it mostly related to noise pressure creep you know it won't hold set point like that dirty one we looked at dirt and debris damage or clogged or scaled up problems or mechanical failure like the failure of the diaphragm or maybe the wrong valve was just installed initially you know maybe you go to a site and valve is just grossly oversized and you have to replace it so let's go ahead and do a poll yeah and if somebody has something other failures that you see that's not on our list by all means send that in we're just trying to get a handle on what what we can make sure that we cover for you and address any issues that we can yeah I mean I'm watching it's still going up until what he ended but by far the dirt debris damaged clogged is you know 61% of the next closest numbers thirteen still go a little bit but by the numbers are moving up consistently and it looks like coming down the homestretch it looks like it's gonna be dirt debris damaged and clogged by nose know by a long way yeah so we got 63 percent of the dirt debris damaged clogged and the next closest would be pressure creep on hold set point which we suspected too and then seven nine percent on the others for Ron Bell noise or failure okay well thanks everybody yeah yeah thanks everybody thanks for that okay all right let's talk a little bit about our valve the 535 h series this is this has been a hugely successful valve for us it's been on the market for a little over a year and sales are going great so what we want to talk about are some of the significant features that differentiate this valve from the rest and I think the pre adjustment knob is one of those you can see it in this picture here it's adjustable from 15 to 90 psi you can tighten down the screw on the top and lock it in place to minimize tinkering and you see that little setpoint window there's one on the back also so if you mount it this way or the other way you'll always have view to the setting on the knob our valve has unions on both sides dual unions 1/2 inch to 2 inch and they're available in sweat NPT press and pecks and press and pecs we're still finishing up a couple of the tail pieces so there are one or two sizes that don't have the pecs crimp yet but in general we've got a great selection of tail pieces we can get it with or without the gauge you see that pressure gauge there that is screwed into a 1/8 inch NPT female connection on the body so if you have a building automation system and you want to be able to monitor all of your pressures from your bis just get the PRV without the gauge and screw in 1/8 inch pressure transmitter or pressure transducer there it's a great place to pick up all your pressures we have a very high Inlet pressure rating 300 psi we meet all the codes and standards that you need of course assc 1,300 °c SI for Canada and as I mentioned the NSF 61 for cold water and up to the 180 degree rating for commercial hot water so also it meets the plumbing codes for North America international plumbing code IRC and the UPC as well so there's that number again that hundred and eighty Fahrenheit for hot water booster systems another really cool important feature is the completely removable cartridge you can see in that diagram that the whole thing comes out and you can clean the screen clean it out put it back in without having to remove the valve body from the pipe really a convenient feature about that if you look at it like there's a classic example if you the other brand I'll go to their next picture that you're going to there you can see to service out pretty much all the other brands I've ever worked on you got to take out like six or eight of those bolts to be able to get into the diaphragm and services some of them they used to have screws on there and the screws the slot would strip out when you tried to get mount it there and there for a long period of time so ours just a simple large Crescent or a channel locks and you can get right into there and the screen is inside the cartridge on ours where the other brands I can't quite see in that picture but there's a separate opening which a lot of people don't realize that separate cap on the bottom of that is where the strainer is kind of hidden in there so when you take the cartridge out of ours you'll have access to the screen which is much bigger diameter also and you know getting hard you can get it back together without we had good points remember that picture with all the dirt that was the screen it goes 360 degrees around the port of the valve so it's it's a very good high quality stainless steel screen so this picture pretty much illustrates the difference between setting the collective valve and setting the other brand of valve okay start comparison let's talk about the precision engineering so inside the heart and soul of the valve is the pressure balanced cartridge because it's pressure balanced it provides extremely accurate and stable control in this cutaway here you can see also the peroxide cured EPDM that's number one a pumped up on top there and the moving parts inside are made of low friction anti scale materials this PPS g---forty that's a poly phenylene sulphide which is a rigid opaque thermoplastic and it has really exceptional heat and chemical resistance and it's becoming a pretty popular material PSU is a poly cell phone which is a very expensive actually and a rigid amorphous material that has a low moisture absorption so those parts fight scale because they're very slippery they can have a drag to about that that why we do the peroxide curing on that EPDM what does that do because I know a lot of others is a standard EPDM but the peroxide care does yeah that's that's for chloramines a lot of water is treated with chloramines and peroxide cured EPDM is the best the best material to use to fight against chloramines so down below in the performance area the flow chamber is where we get the the high performance the minimum pressure drop the minimum drop off right fall off and high flow and you can see this number of five here in the in the diagram this this piece right here is actually a it's a restraint that goes around the stem and it holds the stem very rigidly so that prevents vibration and harmonics and noise and the 360-degree flow path as we saw in that that picture with all the dirt really gives us our our high flow characteristic and it prevents wire drop because we have a 360 degree flow path we don't have you know just one single small opening which could could experience wire draw and what that is is this high velocity water flowing through a small opening made of brass and it can actually erode the brass and carve little tiny seat in the brass which would cause then leak through and you have to replace the seat in the valve so that's what wire draw is I like this picture this cutaway is in our new cell sheet for the 535 it points out some of the internal components and just a nice overall diagram to show off the valve and also want to point out here that all the literature that you need as a contractor as a design engineer as a distributor whatever your your trade we have guide specs you can use to spec the valve the tech brochure has all the technical information in it the instruction sheet for installation you know everything you see here the sell sheet for sales the submitted data for you folks doing submittals if anybody's using Visio out there we have stencils for that and we also have a note list here but BIM object models the three and 2d models for this product for those of you who are using them object excuse me that for using BIM models see what else anything about the literature Bob that pretty much sums that up right and we've got some videos I did a quick video a couple of weeks ago you might be able to find that if you go to the 5:35 H website you'll see a video and a little two-minute me talking about the features and benefits of the valve that's all we had so mark do we have any comments or questions we're on a tee up and thanks everybody for listening hang around if you want to otherwise we'll see you next time in an installation where there is a need for high flow and low flow you had a schematic there that showed an example where the pressure setting on each of the two valves was different by 10 psi is that a golden rule or a rule of thumb well I've seen 10 psi and at least one article that I've read and the technical information from Italy actually says 8 to 10 so basically that's that's what I've I'm seeing out there so if anybody has any other thoughts on that please send that in but you know when you're talking about fall-off - it really it really depends you if you look at your fall-off curve maybe you want it maybe you want that big valve to come in sooner so maybe five psi difference and then when your small valve reaches a fall-off point of 5 psi the big valve kicks in so I don't I don't know that there's any hard and fast rule but those are the guidelines or suggestions very good another question was made referenced in terms of pressure in the building some fixtures will have a pressure requirement to either stay above or below can you give an example of such type fixture there are some tables and I don't have it right on the tip of my tongue that you can look at that have suggested pressures for fixtures it may be in the plumbing code and I've seen like 4 or sinks and laboratories it's like 8 psi for certain types of toilets it's 25 and then those super-powerful high-performance toilets require like 45 if psi to operate so it depends on the fixture and I think also in the fixture specifications themselves you can find the minimum pressure for proper performance oh yeah speaking of toilets I think we had an issue in our own bathroom here and Milwaukee on pressure right we did yeah when art PRV is set above 75 psi our urinals don't work very well they leak so we had to go out and tweak our pRb down a little bit to make sure we were we were below below that pressure and that took care like comment on ball and toilets and stuff too if the pressure gets up through high they'll start to squeal when they try to shut up at the very high end so I thought that the pressure that the plumbing code once upon time said to 45 psi as I suggested but I can't find it anymore I don't know if I that was true or not because I don't know why but every one that I've ever used comes out of the box it says preset at 45 and we do also so I don't know what that number is drive from but certainly have you set up to 60 if you have you know small pipe in your house or something needs a little bit work 45 is the highest rating I've seen on a fixture and that's those high performance toilets I was talking about I've never seen a fixture that has anything higher than that so maybe that's why another question came in I think you showed a rooftop hot-water heater you know in a high building and showing pressure reducing valves question is for plumbing hot water research would you would you want to steer around the pressure reducing valve at each of your circuits or you go through the pressure reducing valve with your hot water recirculation flow you're going to be going through the PRV so that that that valve becomes part of your head loss calculations for that pumping circuit yes so yeah the the PRV is just another valve in in the circuit so you do have to account for that pressure loss at the GPM that your research pump is going to be circulating water at so you know for GPM for example you'd want to look at the pressure drop across that valve but for GPM and count that in your head loss calculations okay that's pretty simple what is a typical range of pressures you typically see in a household or even a light commercial application maybe Bob you might even have a weigh in on that well it depends I know I worked in that in a mountain town Park City Utah and what would happen there is they were developing that that resort around there they would put the water towers up on the top of the mountain that's how you'd have almost a 3000 foot elevation from the from the you know Main Street at the bottom there to the top of the tower so there would be PRV stations every couple what a couple hundred feet I guess I don't know what the exact dimension would be where they'd have to put him in and and we knew when one of those would fail out on the street they usually had him on the ball down the street because we'd have a water heater relief valve and fire sprinkler pressure relief that was popping off in a certain area of town and we knew right away to call the city that one of their big PRV stations had probably got dirt or debris in or something in it and was creeping up and causing a high-pressure condition but you know most of the time you know in that area anyways and where I live in Springfield it's not unusual to see 125 pounds out at the city main again it depends on where you are in relation to the either the brew station or the the water tower if you're right under water tower that's a couple hundred feet town obviously you're going to have that that high pressure but yeah I would say it's all over the map I don't know that you know a designer of water public water systems has a certain number that they try and stay under as far as their laterals and and that branches off that main come through town or not but that's where those big care these stations are typically located okay another question came in and this is in regards to minimum flow rating of a valve so are there any operational or performance issues with flow conditions below the valve minimum recommended flow how does the valve respond for example a single fixture calling for a half gallon per minute floo that's below the rated minimum of a valve I think you're looking at some instability or potential hunting the valve may not control at a very precise and stable level it may increase and decrease and hunt a little bit now that's not always such a bad thing I mean if you have periodic flow that's really low and the valve is a little bit unstable that's not the end of the world you just want to not you know make that a constant thing because then the valve is of course it's not going to be working properly and again you'll be looking at very low flow and control near the seat which you want to avoid we've we've talked about that but you know typically periodically not a problem so Kevin is it do you know if it is it and if you under those conditions is it a condition that you would typically notice at the tap or wherever your fixture is where you got just cracked open a faucet for just Washington you're brushing your teeth or is it more of an issue that's gonna be unnoticeable except for at the valve seat or over time you could get some accelerator where you won't notice it if you're any distance at all really from the PRB if you were right at the you know the PRV in a very short piping run you might notice that but if you're downstream any significant distance you're not gonna notice okay great it was a good question all right I think that might exhaust the questions yeah I think that's it thanks everybody we really appreciate your tuning in and again if you type in a question we will answer it so thanks for attending and we'll see you next month