Check Valve / Flow Meter

jblizzle

0
TFP Expert
LifeTime Supporter
Moderator Emeritus
May 19, 2010
43,184
Tucson, AZ
I was doing some searching for another thread and ran across this product. Looks like a Jandy/Pentair check valve that has had the lid replaced with a flow meter. No telling how well it works, but pretty interesting concept.

I see they have a lofty claim of +/-2 GPM over 0-100GPM range.

http://h2flow.net/h2flow/index.cfm/prod ... low-meter/

flowvis_02.gif
 
Re: Check / Flow Meter

You had to call for pricing ... so if anyone finds out ... report back.

Unfortunately, I think the check valves I just installed are Pentair and they may not be supported. :(

I decided to send them an email to get some more info ... will report back when I hear something.
 
I like it. However, it can't really be +-2, I can't imagine that you could read that indicator that closely even if the position was correct. Still, many flow meters are +-10 or worse, so that really isn't a problem. I also kind of suspect that it adds more flow resistance than a high quality check valve, which could be slightly more of an issue, but still not too bad.
 
That was one question I asked ... if the spring used was stiffer than the regular Jandy spring thus increasing the head loss. If the spring is similar, I can not see why the resistance would be any higher than the Jandy.
 
I got a response back which is included below. A pricing sheet is attached. I could not attach some tech info about the head loss as the file was too big. May try another way.

Dear Jason,
Thank you for your questions on FlowVis® and also for posting your note on http://www.troublefreepool.com
We received a related call from Dave S. regarding your posting – so once again, thank you.
Jason, I’ve answered your questions below (in red). If there are any other topics that you would like to discuss, you can either drop me a note or give me a call.

Best regards,
Paul Hackett
CEO
H2flow Controls

My email with his responses:
Just ran across this product and thought it was a great idea.
I posted up a topic about this on the troublefreepool.com forums as I had never seen it mentioned ... already some interested folks.
Thought I would try to find out a little more information and have a few questions.

I just installed some Pentair Check Valves. Will this work with those valves or only the Jandy check valves? ... I am not sure how different they are or not.

At this point in time, we only have a ‘retrofit’ solution for either existing Jandy or Praher valve bodies. We have done the development work for the Pentair and are working with them to provide us with certain components that are needed from the OEM. The FV-C (which is the complete FlowVis including the valve body), is by far, the most common purchase right now. Also, we chose to have a Jandy based solution first because Jandy has 80+% of the installed check valve market.

Is the spring you use stiffer than the standard check valve spring? Curious how much it could affect head loss in the water flow.

The spring is a little stiffer (~1.5 lbs). The equivalent head loss is equal to one 90 degree elbow, or, in electrical terms max 3 watts of power on a 2.0 HP pump. Please see attached file for more detail.

Does the spring slowly degrade over the 5 years you state resulting in a loss of calibration? Is that why it is recommended to replace the spring? So, really it would just lowly read higher and higher flow rates.

We chose to go with the highest quality spring we could find. It’s manufactured in WI (not China), and is quite expensive. We life cycled the spring to replicate 7 years of use with the pump being turned on and off twice per day. After the accelerated life cycle testing, we were able to confirm the exact same readings as were experienced prior to the test. If and when the spring did start to weaken, the reading would go higher and the spring would need to be replaced. The task is very easy and would take around 5 minutes.

What is the price for the full valve and the replacement lid for existing check valves?

The complete FlowVis is $165 and the retrofit kit is $124 (in small quantities). Please see attached file.

The claim of +/-2GPM over the range is pretty bold given that most of the other flow meters I have seen discussed on the forums are +/-10% of the max flow (10 GPM on a 100 GPM meter). Seems like many people would be interested in this accuracy.

Jason, the accuracy is staggering and it is over the entire range. No flow meter in the market today is tested to NSF50. Not only are we having the FlowVis tested to this standard, we are also asking them to verify our accuracy claims. When we started to do our calibration tests, we purchased a number of expensive electronic flow meters (one of them was $2,700 and it was the least accurate of all of them). One of the paddle wheel meters ($400), seemed to be reasonably accurate, but again, we were far from impressed. At the end of the day, we achieved our calibration by the very simple, old fashioned method of releasing a known volume of water over a know time period, e.g., 50 gallons in 2 minutes = 25 GPM. We asked NSF how they were going to do it, and they said they do the exact same way – it’s the only way you can be certain.

Well, that is what I can think of for now. Thanks for any information you can provide.

Thanks,
Jason
 

Attachments

  • FlowVis Pricing Schedule & Order form for End Users r1.1.pdf
    187.9 KB · Views: 64
One thing to keep in mind is that check valves in general add head loss as the valve closes and as the motor speed decreases. Add to that this check valve has 3x stronger spring and I think the head loss is going to be much higher at lower speeds. I removed the spring from my check valve because I noticed that it was almost closed on low speed.
 
mas985 said:
One thing to keep in mind is that check valves in general add head loss as the valve closes and as the motor speed decreases. Add to that this check valve has 3x stronger spring and I think the head loss is going to be much higher at lower speeds. I removed the spring from my check valve because I noticed that it was almost closed on low speed.

I noticed the same thing with mine on low speed and will likely follow your advice and pull the spring out.

It is a nice concept, but I wonder how important it REALLY is to know flow rate ... based on most of the advice we give, flow rate does not usually matter.
 
I have always wanted a flow meter but was never crazy about the blue/white pitot tube types.

Anyway, I talked with these folks and I really liked the product and their assurance of it's high level of accuracy. I have purchased it in every configuration and will have them in stock on Tuesday.

I would assume those owning or considering a VS pump would find this a VERY hand add-on.

Please PM me if you want any more information on them. :lol:
 

Enjoying this content?

Support TFP with a donation.

Give Support
Well, I am between a rock and a hard spot because I sell them so cannot, in fairness, "extoll their virtues".

Mine has been on my system about 6 months and, even though I don't have a VS, I like it's quality and I like it's accuracy....mine reports the same flow within 1 gpm each time I start it. It is repeatable and actually quite easy to read. If I had a VS, I wouldn't be without one.

PM me if you'd like more info.
 
Love mine. I'm using it with a VS pump as well as solar. I run 100% of the return through the solar and it allows me to use a single flow meter after the filter. With the solar bypassed, 25 GPM is 1250 RPMs and 160 watts. With the solar, 25 GPM is 1850 and 415 watts.
 
mas985 said:
One thing to keep in mind is that check valves in general add head loss as the valve closes and as the motor speed decreases. Add to that this check valve has 3x stronger spring and I think the head loss is going to be much higher at lower speeds. I removed the spring from my check valve because I noticed that it was almost closed on low speed.


Not sure if this pdf was out when the topic was first active.... http://h2flow.net/h2flow/assets/File/TechTips_Effect on Head rev4.pdf
 
I am about to purchase one of these from the TFP website (along with my TF-100 test kit :cool: ), just wanted to know if anyone has been using it and their results? My pool is almost complete and uses a VS pump for about 25,000 gallons. Also I plan to install myself, do I install after the pump before the filter, after the filter before return lines, etc??? Thanks in advance.
 
One of the nice things about the FLOW-Vis is you can put it anywhere you want. It has none of the limitations of the Blue-White style meters. Mine is before all the equipment but the flow will be the same regardless where you place the meter.

I used to start my pump and watch my psi for expected pressure. Now, I start the pump and watch the Flow-Vis for expected flow rate. I find it a very handy tool even with my single speed pump.

For what it's worth, my psi only dropped a 1/4 pound, if that, when I put the meter in, so whatever head loss it has added seems to be pretty small in my unscientific opinion.

As posted above, I have an agenda in that I sell them so take my opinion only for what it's worth.
 
I bought one of these valves and hoped to have in installed on my system when adding some solar panels. I found out though that it might cause some problems with the SVRS system. Apparently you can get the valve with a non-sealing flapper, but it's not clear exactly how you do that. I tried to call the flow-vis folks, but I haven't really gotten anywhere with that. Anyone know?
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.