Anyone use or install a Flume2 water monitor

[jwiegley]

After reading This thread I ordered a Flume 2 and installed it, and immediately found a problem in my setup: lack of check valve and elevated spa was causing 150 gallons of spa water to overflow into the pool (and out to the city), which was then replaced via auto-fill once the pump turned back on. I could see this happening before, I just didn't connect in my brain how the water displacement was basically flushing 150 gallons daily.

But now I'm finding that every morning, around 7:50am, what could only be the auto-fill (1gpm) kicks in and uses 50-100 gallons a day. I'm going to confirm this by turning off water to the pool for the next few days. But I'm wondering, why is it doing this and why so regularly around that time? It's not exactly the same time each day, but is there some kind of threshhold that daily evaporation reaches around the same time each day?

 

[kul]

But now I'm finding that every morning, around 7:50am, what could only be the auto-fill (1gpm) kicks in and uses 50-100 gallons a day. I'm going to confirm this by turning off water to the pool for the next few days. But I'm wondering, why is it doing this and why so regularly around that time? It's not exactly the same time each day, but is there some kind of threshhold that daily evaporation reaches around the same time each day?

This amount of evaporation seems odd given current temperature and weather. Is your pool heated at this time?

I also have the flume 2 and it has been helpful for when my kid doesn’t turn off a sink all the way.

 

[JoyfulNoise]

Do a bucket test. That will rule out evaporation versus a leak.

 

[jwiegley]

No, it's not heated. I've had a leak detection company come two different times, and they only found a small leak in the spa that they patched up. I'm pretty sure irrigation is leaking too, but that is set to only run once a week right now.

 

[jwiegley]

I've done the bucket test a couple of times now and not noticed anything significant, but it's worth another go to help rule this out.

 

[JoyfulNoise]

Does anything else run at 7:50am?

Can you turn off the autofill at 8:10am and see the Flume show a drop in flow?

 

[jwiegley]

That's a great suggestion, @JoyfulNoise. For tonight I've turned off the pool systems, shut off auto-fill, and put a bucket in. If that resolves it, then I'll do the "mid-fill" test just to be sure.

I was wondering for a moment if the "system under pressure" had an aggregate higher water level than the "system at rest", with the differential creating a overflow that needs to be filled in each day, but that would only make sense if the auto-fill kicked in at or after the pump turned on, and not 15 minutes before.

 

[jwiegley]

And btw, I do think the spa has a higher level when the pump is running — as evidenced by the water that still flow out for a few minutes after turning off the pool — but at best it's 5 gallons or so.

 

[Ahultin]

as a result of the flume and out of a desire to be able to check the pool auto fill water usage, I added a solenoid to the auto fill supply powered off my intellicenter and scheduled for 1 hour daily at a time that no other water "should be" in use. You could do similar off of your intelliflo3 if you have the relay board and are not already using both available auxiliary ports.

 

[kul]

Do you have sprinklers on a timer? I’d look into all outside watering. Or do you maybe have a leaky toilet that is refilling? Though maybe not since it’s at a specific time….any appliances that use water around that time frame? Dishwasher?

 

[jwiegley]

We program the dishwasher to run at noon, and the sprinkler is set only to run every Sunday. All the other hours of the day are pretty much zero, except for showers, washing dishes and using the kitchen. So just this one "leak" to track down.

 

[Dirk]

For reference... We have relatively similar climate. I shut off the source to my autofill several months ago, and while I have observed water leaving my pool via my overflow system during a rain, rain alone has kept my water level well above normal. It was hardly dropping at all even before the rain. You are not losing water to evaporation, let alone 50-100 gallons a day.

 

[Dirk]

Could this be a clue? According to my temperature monitoring system, 7:50am-ish is when the air really starts to heat up. The temperature is not consistent from day-to-day at that time, but when the air hits its lowest point, and when it later starts to really warm up is pretty close to the same time each day.

Could something be contracting in the cold in the early morning, losing water, and then sealing itself up for the day later in the morning each day? Pretty farfetched, just looking for something that happens each day, but not at the exact time each day.

 

[Dirk]

Is someone taking a shower around that time each day? Perhaps triggering a pressure drop (due to an aging pressure regulator) that then triggers something else that uses or loses water?

 

[jwiegley]

@Dirk Some interesting thoughts. Now that the auto-fill is off, the mysteries ~150 gallons each morning is indeed gone. Going to let it go for a few more days, then turn it back on and check again.

I did do the math, and give my pool's surface area (794 ft²), an evaporative loss of 0.25 inches translates to 124 gallons ((0.25in / 12) * 794 * 7.48). Since I'm in Sacramento and the climate is fairly dry most days, this makes a bit of sense. I am a bit surprised if it's waiting to do all of its refill at one time, though. It's not always >100 either. Recently the weather has been getting much more humid, and I saw a loss of only 85 gallons during that time.

 

[Dirk]

@Dirk Some interesting thoughts. Now that the auto-fill is off, the mysteries ~150 gallons each morning is indeed gone. Going to let it go for a few more days, then turn it back on and check again.

I did do the math, and give my pool's surface area (794 ft²), an evaporative loss of 0.25 inches translates to 124 gallons ((0.25in / 12) * 794 * 7.48). Since I'm in Sacramento and the climate is fairly dry most days, this makes a bit of sense. I am a bit surprised if it's waiting to do all of its refill at one time, though. It's not always >100 either. Recently the weather has been getting much more humid, and I saw a loss of only 85 gallons during that time.

I guess our climates could be different enough. I just know no fill water has been added to my pool in at least three months. Not a drop. I have a, let's just say, unorthodox level monitor, that gives me a visual readout of my water level above the bottom of my skimmer opening. For three months it hasn't been below 4.5". Right now, with some recent rain, it's back at about 5". It never gets higher, as it drains off through my overflow.

Some water is, of course, evaporating, but it's so little, and is being replaced by rain, and we haven't had much. Like I said, I suppose our climates could be different, but by how much? I am using zero water from the street, and I regularly watch excess drain off.



3.5" is where my auto-fill kicks on. 5" is where my overflow drains off water. My pool hasn't been below 4.5" for many months. My auto-fill has been shut off all that time.

Was your auto-fill off when you did the bucket tests?

You could rig up something similar. Tape a ruler to your edge tile. With your auto-fill off, your 1/4"-a-day theory should be easy enough to prove or disprove. Do a bucket test at the same time. Put a ruler inside the bucket, too. If it is evaporation, both rulers should track the same loss.

Did you mention? Is your auto-fill valve like a toilet tank fill valve? That's what I have. If yours is like mine, it's not filling every time there is the tiniest drop in level. There are thresholds (for lack of a better term). The level drops quite a bit, then the valve kicks on. Then the valve stays on for a while, even overfilling a bit, then shuts off. I don't know the measurement of the difference in water level this translates to, but it could be a 1/4" easy. I hope I'm explaining that well enough.

Now why that would happen at about the same time each day is still a mystery, but it could be air temp related. Or pressure related. That's why I asked about the morning shower. I don't know this for sure, but I suppose a sudden drop in pressure on the auto-fill valve, caused by a weak pressure regulator and a shower or toilet flush around that time, might trigger the auto-fill valve. Then once it gets going, it stays open for that 1/4" refill. Really just guessing here. But it could be something as simple/complicated as that.

Do you know? Do you have a backflow preventer connected to your auto-fill line? They trigger based on the pressure differential between input and output. That could be part of the equation.

Do you have any symptoms of a bad pressure regulator? Low pressure? Significant pressure drop at one faucet when another is turned on? Banging/clanging noises?

 

[jwiegley]

Thank you so much for talking through this problem with me.

Was your auto-fill off when you did the bucket tests?

Yes, the auto-fill has been off for two days now.

Is your auto-fill valve like a toilet tank fill valve?

Yes, in fact it is exactly a toilet tank fill valve that I purchased at Home Depot. I recently replaced it.

The only odd behavior I've noticed with this valve is that the chamber where the auto-fill lives is slightly higher up than the pool it is filling. This results in a cycle where water fills the chamber where the valve is, stopping the valve, but then flows out more slowly to the pool and drops, and thus turns the valve back on again. So whenever the pool fills, it does so by "pulsing" the valve on and off for about an hour. If it filled slower, or if the drain to the pool were larger, then I imagine it would be more consistent.

That's why I asked about the morning shower.

Our morning showers have been happening either much earlier or much later than the heavy flow I've been measuring with the Flume.

Do you have a backflow preventer connected to your auto-fill line?

There's no check valve on my auto-fill line.

Do you have any symptoms of a bad pressure regulator? Low pressure? Significant pressure drop at one faucet when another is turned on? Banging/clanging noises?

Not that I'm currently aware of...

 

[Dirk]

The only odd behavior I've noticed with this valve is that the chamber where the auto-fill lives is slightly higher up than the pool it is filling. This results in a cycle where water fills the chamber where the valve is, stopping the valve, but then flows out more slowly to the pool and drops, and thus turns the valve back on again. So whenever the pool fills, it does so by "pulsing" the valve on and off for about an hour. If it filled slower, or if the drain to the pool were larger, then I imagine it would be more consistent.

Yah, the auto-fill is a gravity-feed, water-seeks-its-own-level dealio. The valve is putting water into the well faster than it can feed the pool. If you had a proper backflow preventer (not just a check valve), it has valves that you might have been able to adjust the flow rate down some.

Unrelated to your current issue, there really should be a backflow preventer. I have a dedicated one for the auto-fill, but if there is one anywhere between the pool and the street (source), then that counts. Something like this:

Amazon.com

Some cities have code requiring one. This is a topic for another day.

 

[Dirk]

If you are convinced the bucket test rules out a leak, and this is, in fact, only evaporation, then I guess it is what it is. The "why" of it happening about the same time each day doesn't really matter, does it?

A cover would reduce evaporation. I think even one of those bubble-wrap covers would help.

 

[jwiegley]

I wouldn't say I'm convinced. I think I need rulers on both sides of the bucket to really see what the measurement is. To date I've been doing the "two finger test" where I drop my two fingers down to see which one touches which body of water first. So far, this has been pretty equivalent.

Another reason I continue to worry about a possible leak is that my CH and CYA keep dropping. They don't drop fast, but they aren't anywhere NEAR as stable as my reading would indicate. I've been having trouble keeping CH above 300, and so far I've added 70 pounds of Calcium Chloride in the past three months.