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