[bailey190]

How to determine what pressure switch to use 30-50 40-60 for a submersible pump well water system with a flotec blader tank fp7120 35gal.cap.

[EPMiller]

How much vertical distance do you have from the pressure tank to the highest fixture? For a 2 story house an 30-50 is usually fine.

[albinfla]

Personally, I prefer 40/60. Your tank can handle it fine, and your pipes should be able to also. Remember to set your air charge on your bladder tank to 38 if you set it at 40/60.

My personal well runs at 50/70. I like the pressure better that way.
Al

[EPMiller]

Personally, I prefer 40/60. Your tank can handle it fine, and your pipes should be able to also. Remember to set your air charge on your bladder tank to 38 if you set it at 40/60.

My personal well runs at 50/70. I like the pressure better that way.
Al

albinfla, you may do it for yourself but don't encourage others to push water pressures that high. Many toilet tank valves will not work correctly at those pressures. We just installed 60 or so name brand toilets in one apartment complex and many are not shutting off before they overflow. Water pressure is high at that location. I haven't checked exact numbers yet because I am not the contractor. I'm the guy that will have to maintain them. :eek:

To the original poster. Set your minimum pressure to 1 psi for every 2 feet of lift from your tank to your highest fixture plus 10 to 15 psi. Set your max about 20 psi higher. In a 1 story house a 20/40 is fine, in 2 story use a 30/50. If I have a situation with water in the 3rd floor I will wind it up a little bit. Say 35/55. I do agree with albinfla on one thing only, set your pressure tank 2 psi lower than the cut in pressure.

There are few things that require more pressure than the above guidelines. If you are using blow out toilets you need at least 20 psi at the fixture, this will change your required minimum pressure, but they are commercial units, almost never found in homes (VERY noisy). Any pressure above what is necessary just wears out faucets, valves, seals, and even the piping. If flow rates go too high you get erosion inside the pipes. I hope albinfla has his house piped with galvanized steel, it has the best wear characteristics for high flow!

EPM

[albinfla]

Interesting... I can count on one hand the number of pressure switches that I have encountered set at 20/40. After nearly 20 years in the water treatment business. City water runs 80-100, regulated to an average of 60 here in central FL.

Almost all commercial customers have to have above 40 at the lowest, or their toilets won't shut off.

I guess it's just a regional thing. I would be curious what Milo or Speedball1 have to say about their experiences. These regional discussions get interesting.

My house is piped in PVC/ CPVC. Galvanized steel doesn't do well in FL due to corrosiveness. We have to do corrosion control on municipal supplies frequently. It has to do with a combination of factors... ph, alk, tds, calcium, temp... known as langlier index. It also attacks copper causing pinholes.

Although I run mine leaving the well at 50/70, I do have psi loss getting it to the house. It goes 150' to the house, up about 6' of rise over the length of 1-1/4" pvc pipe. I haven't calculated the head/ friction loss, or even put a gauge on the house. All I know is, I like have decent water pressure in all 3 bathrooms if all the showers are running at the same time. Or more importantly, if I'm in the shower, and somebody flushes, I don't want to get blasted with hot water. Or, dance around to rinse soap! :)

Al

[speedball1]

I guess it's just a regional thing. I would be curious what Milo or Speedball1 have to say about their experiences.

Unless the utility company kicks the PSI up the average house pressure is about 45 PSI. That's why city water towers are 100 feet high. Because you get about 45 PSI at the base. Think about it! More pressure means more strain on joints ,valves and faucets. Some cities are forced to raise the city main pressure to service outlaying areas. This, in turn, forces the home owners closest to the source to install a PRV,(pressure reducing valve) on their water service to bring it down to a usable pressure. In my estimation 30/60 should be tops. Regards, tom

[albinfla]

Tom,
Thanks for the input. I agree that 60 should be tops. I figure that is about what mine coming into the house is after softening, filtration, and headloss.

I'm sure you know this, but many municipal supplies have gone to storage tanks on the surface of the ground.

In Tampa, their lead operator told me that they are required to keep 70 psi anywhere on the main. In Gibsonton the average psi off the street is 90-100. Of course that is regulated down to 50 or 60 in most cases.

Obviously, the higher the pressure, the more stress on everything. But, 20/40 is extremely low. A low-flow faucet would get a dribble at 20/40. The most common well psi setting I have seen for residential is 30/50, for commercial is 40/60.

There are certainly exceptions... one of my newer luxury home communities that I do the water treatment for requires 62/82. Then, they regulate it leaving the plant at 62. And, they still have people that complain about pressure.

Thanks to bailey190 for our enduring our ramblings!
Al

[EPMiller]

Tom,
Thanks for the input. I agree that 60 should be tops. I figure that is about what mine coming into the house is after softening, filtration, and headloss.

There will be a loss through the filter and softener when there is demand, but when there is no demand the pressure throughout the system will be equal to the pressure tank less the head loss. This no-demand situation in high pressure applications is where the problems with valves and any other shutoff mechanism rears it's head.

<snip>Obviously, the higher the pressure, the more stress on everything. But, 20/40 is extremely low. A low-flow faucet would get a dribble at 20/40. The most common well psi setting I have seen for residential is 30/50, for commercial is 40/60.

I agree, 20/40 is minimum and with flow limiting fixtures I would like to see close to 20 psi at the fixture, but IIRC, that is the standard operating pressure for modern faucets. I have seen plenty 20/40 pressure switches around here in older single story homes though. Probably because in the days of big bore faucets there was NO problem getting enough flow. Commercial installations often need higher pressure because of using blowout fixtures, the pressure is what gets the flush going.

There are certainly exceptions... one of my newer luxury home communities that I do the water treatment for requires 62/82. Then, they regulate it leaving the plant at 62. And, they still have people that complain about pressure.

Thanks to bailey190 for our enduring our ramblings!
Al

Anybody griping at 60 psi doesn't understand residential plumbing. Tell them to put in a booster pump. :D Have a good day.

EPM

[jlisenbe]

Great discussion guys. Everyone should read this one. A lot of experience speaking here.

[albinfla]

No kidding about not understanding pressure. I agree that 60 should seem sufficient. Except that I think a lot of homes... even big new fancy homes have plumbing issues. Therein lies the problem. How they ever pass inspection is beyond me. That same community tested at 58 curb-side of their RPZ, with water flow, 50 dynamic across the RPZ. They originally complained because they said my treatment plant worked had dropped their water pressure. They did have some buildup in the strainer. But after cleaning the strainer, we had 53. Then, they still didn't have pressure upstairs. So, I spent time showing them at several locations exactly what they had.

Here are my test results...

At the house tested at about 48. After their softener about 43, at their inside downstairs laundry faucet 38, upstairs bath only 22 at the sinks' supply valve. All of these were taken with one sink flowing moderately upstairs on the opposite side of the house of where I checked for 22.

After all of that, I suggested they call a plumber to see if he could help them further. Obviously we did our due diligence since we had only done work all of the way up the street at the community's water treatment plant.
Al

[EPMiller]

No kidding about not understanding pressure. I agree that 60 should seem sufficient. Except that I think a lot of homes...even big new fancy homes have plumbing issues. Therein lies the problem.<snip to save bandwidth>

Yeah, I sadly have to agree that a high percentage of problems are caused by poor installs. Most supply plumbing that I see is done using LAR (Looks About Right) or FWP (Fastest Way Possible) engineering, or some low cost combination of both. :( And the bigger the house, the more possibilities for problems. :)

That house exampled in the above post must have had lots of undersized pipes with many elbows. The way to show the homeowner that the pipe was undersized (if it truly was) would have been to leave the gauge on that 22 psi location and shut off all demand. If the pressure went up to the supply pressure less vertical head loss, then the losses were all in flow restrictions. (If not, there's a leak! :eek:) One of my pet peeves is using too many elbows. A 90 degree elbow in 1/2" pipe is equivalent to 6' or so of straight tube IIRC. Bigger pipe has even more equivalent restriction for an elbow. That is one of the beauties of pex. Use bend supports or broad sweeps instead of elbows, they really reduce flow restrictions. Many plumbers learned on copper or cpvc, and they use the same methods on pex. Given it's smaller internal diameter, and even smaller ID fittings, what would have been marginal before is now a problem.

EPM

[EPMiller]

albinfla disagrees: 20 psi will give a dribble inside... jerk!

I'm sorry, am I missing something? I mentioned nothing about 20 psi in that last post. You posted disagreement with it and then called me a jerk?

To reply to the first part of your disagreement: I know some of our group homes have 30/50 pressure switches in the basement and in the living quarters on the 2nd floor they would drop down close to 20 psi at the fixture at cut in, and they don't dribble.

As to the jerk part... If this is the way things go on this forum I will respectfully submit that I don't think I will be showing up here much any more. I really have plenty of work to do on a day to day basis and was just giving a bit of time here to help and to educate those with questions. I am not here to have my ego stroked, but I don't need to put up with that, and by leaving I'm sure that I can do some good by lowering your blood pressure.

I consider myself a careful mechanic that does quality work and wants to help my employer and customers to avoid problems. I have tried to help those here that I felt I was knowledgeable enough to help and have tried to head off problems in the making by those that I felt were off base when they answered questions. I did not intend to infer by my disagreement with the way you set the pressures in your own house that you had no knowledge or skill. You obviously can repair and maintain your own house, but I reacted to what you said because I know the problems that COULD (I did not say WILL) arise if someone was going to follow your lead without knowing the other side of elevated water pressure.

I will check on a few threads that I am contributing to and the I bid you a good day.

EPM

[albinfla]

The jerk part came because you had absolutely no reason to give me a red dot because your opinion differed from mine. It completely ticked me off. Then, you comment that I should have my system engineered. Once again, a personal attack on my expertise. Calling you a jerk publicly was a mistake. I admit that. Admittedly, it was only in retaliation for the reddie!

Usually the professionals on here don't do that to each other. You can't tell this by the order of posts, but we were having a professional debate. Then, I realized that you threw a reddie at me. Then, I blew. The experts may debate in the forums. But, they don't throw reddies at each other. Because when dyi'er comes on the forum for advice, they won't trust their advice. Remember, we ALL volunteer here. We all donate our time and expertise. I do it as sort of a giving back to a profession that has been good to me. And, I enjoy helping people. Probably every expert here does it for the same reasons.

If you look back at my advice, it was to instruct them that it is okay to have the pressure switch at either 30/50, or 40/60, the pressure tank is okay for either. Then, I went on to say that I set my own at 50/70 because I want pressure. You were advising 20/40 psi as a well setting. Usually the only 20/40 settings on wells is if the people dramatically undersized their well equipment, and that is all it will run at... say, a deep well pump with a 1/2 horsepower pump. However, 20 psi at the well will hardly create enough pressure in the home to be satisfactory.

If you were to take a consensus of everybody who has a well, you would find that a very low percentage have a 20/40 pressure switch setting. This is further confirmed by the fact that almost every bladder tank comes pre-charged for a 30, or 40 psi cut-in setting.

In your last post, you said that they have a 30/50 setting and the faucets don't dribble with at least 20psi at the faucet. My point exactly... if it were 20 leaving the well, it would theoretically be 10 at the shower. That would be a dribble! This would be especially true if they had a low-flow design shower-head. So, again you confirm that you would not want a 20/40psi switch setting!

30/50 or 40/60 in almost every case should be safe for most homes. Think about it, even at 60 leaving the well, with head loss it will not be any more than most city water psi regulators. But if it is an older home with pipes that somebody is uncertain of, stick to the lower psi of 30/50.
Al

[speedball1]

Ya both were wrong! Miller, we don't give reddies because we disagree with another experts statement.
John, We don't attack another expert by calling them names.
Not a big deal guys! Simlply common courtesy. There will be times when we disagree, Milo, growler and I do it all the time. I don't agree wth their code restrictions but I don't bang them with a reddie or come down on the expert with a bad name. I go after the UPC but not the experts that are forced to follow it. In short, If you disagree with another expert leave personalities out of it and go after his content.
Play nice children!! Tom

[albinfla]

You are right Tom. We were both wrong. I should've left the name calling off. I overreacted to the reddie, which seemed like a punch in the eye. I punched back as a reflex reaction. I thought the content was leading to a healthy discussion of pressure that would benefit everybody. Then, I realized back on the other page that he slugged me with a sucker punch. I should've relaxed, and continued the debate. But, it really seemed out of line. So, I retaliated.

I can debate with somebody all day long. I have to do that with inspectors, engineers, etc. I enjoyed your debate a month or so ago when you basically chased the kid off the playground because he was not necessarily correct. I don't think anybody threw any reddies over that discussion. Nor, should there have been. It was a discussion. That is what I thought we had going here. Until I realized I was sucker-punched.

I should've turned the other cheek. I should've just said... oh well, my first reddie! Given the nature of people, I'm sure it won't be the last! Even if we are giving free expert advice that we normally get $65-100 per hour to give.
Al

[EPMiller]

we don't give reddies because we disagree with another experts statement

I did not realize that a "reddie" is something that mattered so much! I clicked on rate this answer and the options are agree and disagree. I disagreed, but I didn't realize that by doing so I was doing something that was beyond the pale.

I also did not realize that I was replying to another "expert". I have only been here since February '08 and I see I am not familiar with everyone's standing on the forum. I apologize that I caused a furor. I will not do it again.

Have a good day gentlemen.

EPM

[albinfla]

Shake hands... all good! Let's all move on. Remember why we're here.

Al

[speedball1]

Now THAT'S the way to end a disagreement. You are both excellent posters. But from time to time even "excellent posters" disagree. We just attempt to avoid bloodshed when it does.
Miller;

I did not realize that a "reddie" is something that mattered so much!

It doesn't to most of us who have been around for years. Some time back we were given the option to opt out of the greenies and reddies. We could opt for a black box instead and a lot of us did just that. That's no longer on the table so we work with what we have.
Favorable comments,(greenies) add to a experts reputation while unfavorable ones,(reddies) detract from it. If you're going to sock a reddie to someone explain exactly why you disagree and run a correction. If you can't correct a post you disagree with then a reddie is uncalled for. This is no way a criticism aimed at you, Miller. Simply trying to explain the importance of reputation points. Cheers to all, Tom

[mygirlsdad77]

The pressure swith is preset a certain cutin cutout. But most are adjustable. I would just buy the 40-60 and adjust to where you are comfortable with the pressure. However, don't go above sixty.
If your plumbing can't handle 60psi, then I wouldn't call it plumbing. Most codes require psi not to be higher than eighty before mandating a pressure reducing valve. In no way am I suggesting that 80 is okay. Just what code says.