WHAT IS THE smallest LEAK PHYN PLUS CAN DETECT?

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The goal of this post is to discover the smallest leak Phyn Plus can detect. My last video covered medium to large loss leak scenarios, but at some threshold Phyn doesn’t cut the water off. Instead, the daily plumbing check discovers the smaller leaks.

For instance, when we first installed Phyn, I was running 8 hour tests to determine the smallest leak I could detect with my water meter and a water pressure gauge. None of the attempts were strong enough to get cut off in the evening when I first started the tests, but a few were discovered in the automatic nightly plumbing check.

There are a couple items that are important to know as we go over the results.

Phyn publishes their plumbing check thresholds and explains their measurements. I have a link to this page in the description. It is especially important for you to click on the link and verify for yourself because I can’t change this video, but they can easily change the website as the developers improve the system. In any case, you can see an automatic plumbing alert depends on two things: an estimate of the diameter of the leak and the drop in pressure for the duration of the test.

Phyn Plus plumbing check thresholds

So what does that translate to when I’m simulating a leak coming out of my kitchen faucet? A drop of water just under 4 and a half seconds out of my home’s plumbing is not enough to trigger a leak notification. A drop just over 4 seconds is enough.

Phyn Plus 4 second drip plumbing leak test notification PSI drop

While the health test didn’t catch a leak the size of a drop every five seconds, honestly, with the way the Phyn app shares the details, you can catch a leak of this size on your own without too much effort.

Phyn Plus results with a leak not detected on a drop just under 4.5 seconds.

Phyn can ACTUALLY help you discover a leak WAY smaller than a drop a minute. I’ll cover both methods towards the end and stay focused on the automatic and manual health checks at the moment here.

Here’s the second point to note with regard to the results. When it came to running these tests to share with you, I specifically wanted the nightly check to catch it and not run manual checks back to back, to give this video a more realistic scenario of how it would work in your home.

If you are trying to compare my results to what you might see in your own home, the problem is, these tests are very dependent on a few factors. First, and most importantly, it depends on the amount of plumbing in your home. If you have less pipe, Phyn Plus will detect an even smaller leak and if you have more plumbing than my trunk and branch system, it may not catch a drop every 4 seconds. If you have a manifold, you can turn off all the valves and individually test each line, which Phyn would perform beautifully.

Other factors include thermal expansion and the time of day. During the test above you can see the runup in temperature where the unit is located outside.

Time of day and seasonal temperature differences affect Phyn Plus leak test results

While the heat of the afternoon is increasing the pressure in plumbing outside as well as in our PEX bypass in the attic, the water in the storage water heater is cooling since I turned off the water heater to make sure it didn’t interfere with the number of tests I was running.

Daytime temperature increase impacts Phyn Plus plumbing test sensitivity.

If I ran this same test at night, I might be able to get a slightly smaller leak because the temperature is dropping.

Now here’s the really interesting part, which is a special feature of the Phyn app. They share the results of the plumbing check right in the phone app. You’ve probably already noticed the psi measurements as we’ve gone over the results, but not all water monitor systems share this information. When you scroll through the plumbing check results, which keeps the results of 60 plumbing checks, you can clearly see the start and ending PSI from each test.

This is what a normal week looks like in my home.

Phyn Plus baseline plumbing check results with no leak

My home’s plumbing fluxuates between a .06 and .14 PSI drop in the nightly plumbing check. I have a storage water heater and the drop is due to thermal contraction. Unless you have a tankless, or your water heater is completely cooled you aren’t going to get away from a drop in pressure during the plumbing check, unless Phyn happens to catch a heating cycle, which is a rare occurrence and that runup you see only lasts 5 minutes as seen in this past video.

However, it does mean you can keep track of these numbers and notice if you start moving in a downward trend. For instance, I actually had a gasket fail on our toilet diaper sprayer. I was pretty upset about this when I first found it–I thought one of our kids was jacking around in the bathroom only to find there was a legitimate leak. For those of you who saw my video on how to change a toilet supply line where the old one failed, well, this seems to be the unlucky toilet in the house. In any case, Phyn didn’t send me an alert on this issue, and you can see by the time I figured out how to shut it off, it was up to a drop every 8 seconds.

New leak PSI drop over time using Phyn Plus PSI drop.

However, it is possible to detect a leak, just by knowing your baseline numbers and looking at the app on occasion. Unfortunately, there is no way to export this data at this time so you can’t make your own automated excel type tracking like you see here, but you CAN see the leak was clearly on it’s way to being detected.

So now let’s discover the smallest leak I can find manually with Phyn Plus on my house with a normal test. Recall, a regular plumbing check on my home sees a drop in psi between .06 and .14. Based on those numbers, I’d like to see a drop in pressure of at least .3 psi, essentially doubling the larger side of the regular drop in psi.

A leak with a drip every 6.5 seconds has a psi drop of .8 with 28 drops of water during a normal 3 minute test.

Phyn Plus 28 second drip plumbing test PSI drop.

A drip every 14.5 seconds has a psi drop of .51.

Phyn Plus 14 second drip plumbing test PSI drop.

A drip at almost half a minute, which only allows 6 drops out of the kitchen faucet during the regular 3 minute test, has a drop of .23 psi. So a drop every 25 seconds is manually detectable using phyn plus on my home if I’m aiming for a .3 psi drop.

For comparison, the day I ran these tests, the regular check showed a drop of .07 psi and .08 and the extended check showed a drop of .28

Now its on to how to discover a leak of less than a drop a minute with Phyn Plus: overnight testing. If you saw my video on how small of a leak you can detect with a water pressure gauge, this is EXACTLY the same. We’re capitalizing on Phyn’s pressure sensor.

First, if you have a tank style water heater you’ll have to completely cool the water inside so that thermal contraction does not impact the results of the test.

Phyn Plus baseline test with cooled water heater

I covered thermal expansion specifically with regard to it’s interference with detecting a minute leak in this past video.

I’m not doing a screen recording of the Phyn app on my phone all night, but you click on this video it will take you right to the timelapse of the water pressure gauge behavior on a night with the water heater still on:

Once you’ve eliminated thermal expansion, turn off the water shutoff to the house and make sure NOTHING uses water for the duration of the test. Then, write down the pressure reading at the start of the test.

Phyn app screen capture to detect a pressure drop

Just as I did in the water pressure gauge test in the spring, where my goal was to get a drop in pressure of 5 PSI, a drop of water about every 4 minutes will drop the pressure in my home’s plumbing by 3 PSI over the course of 8 hours in the summer.

Phyn Plus 8 hour test PSI drop

At the end of 8 hours, or whatever duration you run the test, compare the beginning pressure reading with the ending pressure reading. If there is a significant enough drop, you have your answer. For completeness, the baseline 8 hour test without a leak and the water heater completely cooled did not see a drop in psi. However, you have to take into consideration my own circumstances, with exposed plumbing and this test was done in the summer. It would be closer to a drop of 5 psi in the winter when we have a much bigger drop in temperature overnight. So you can see why I’m calling a drop of 3 PSI enough to convince me there is a leak in this situation.

Phyn Plus summer vs winter temperature differences

This small of a leak will never be caught in an automatic or manual plumbing test and it is unrealistic to expect it to. But it is possible and that’s part of the fun of thinking about what you can do with these kinds of systems.

If an 8 hour test is not in the cards, you can also completely cool your water heater and then repeat a regular or extended check as we did right before this to detect a leak smaller than a drip every 25 seconds.

Again, your results will be different just because there is a difference in the volume of water between your plumbing and mine, but this still gives you an idea of what Phyn Plus is capable of on a real home of about 2,000 square feet with a trunk and branch system.

If you are looking at this post because you think you have a lot of false positives in your nightly plumbing check and you can’t find the leak, I encourage you to get it professionally checked out. Phyn doesn’t have a lot of false positives and ignoring nightly plumbing check alerts or disabling the automatic checks defeats the purpose of having one of these kinds of devices. Discovering the source of the problem and getting it solved will give you peace of mind and helps Phyn keep your home safe.

In a coupe weeks I’ll be releasing a new video which compares these results to Flo by Moen and another where I compare water monitor solutions to other leak testing methods. This will give you some insight as to how well these different tools work when it comes to detecting leaks within your own plumbing.

Phyn Plus (10% off) – https://www.phyn.com/plus-smart-water-assistant/ enter discount code ‘Margaret10’ at checkout

For other pricing/reviews: Phyn Plus on Amazon

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