Backwashing system running well dry??

Hello all. Sorry for the long post, yet I was wondering your thoughts on a recent problem that I started to have (in addition to the water hammer mystery I’ve posted about previously)

A little over a week ago, I had a pellet-drop chlorinator installed on the well, and a backwash system installed in the home. As I have high iron levels in my well water (along with other contaminants) the 19-year old Ferromax Reionator filtration system I had just wasn’t doing the job. I have never had any issues with water pressure or quantity since I’ve owned the home (I have close to an 8gpm flow rate).

Shortly after the install, I came back home after a 4-day trip out of town, and noticed that I had no water. I checked my pressure tank, and it was at “0”. Thinking my pump may have failed, I called a local driller/well specialist, and he came over and verified my pump was still outputting normal amps. Since the backwash system was scheduled to backwash every night for an hour (using 50 gallons of water per cycle), he said that the backwash system may have run my well dry? (Or maybe I had a leak somewhere?)

I contacted the guy who recommended and installed this system, and asked if it was possible that the backwashing may have depleted my well? He didn’t think that was possible. So, in order to just get enough water for a 5-minute shower now, I have to leave the well pump off for several hours, and then turn it on to hopefully fill the pressure tank to cut out at 60psi. On very rare occasions will the pump replenish the tank once it gets to cut in at 40psi. Usually, at cut in, there just isn’t enough water and it drops to “0”.

My question is: could this backwash system have run the well dry? If so, does it usually take this long to get my normal water quantity back? Never having any issues with water pressure or quantity before the installation, I’m led to believe the backwash system is the cause of this problem?

Thanks for your time in reading this lengthy post, as well as any input you may have!

 

Does your pressure switch have a lever on it?

 

Hello Reach4...as always, thanks for taking the time to reply.

I’ve attached a photo of my pressure switch. The only lever I’m aware of is the horizontal, white plastic lever that connects to the 4 wired boxes with screws on top. I can pull that lever back, and when it snaps forward there is a small electrical spark that occurs. Is that the lever you’re referring to?

 

That was not the lever I was asking about. I was wondering if you had a low-pressure cutoff switch, and you don't.

So while you are waiting to get up to 60 PSI, what does the pressure gauge say?

So why is it dropping to zero? I presume the pump overheated, and the thermal cutout cut the pump off. But are you using water then -- maybe just refilling a toilet tank, or what?

I am just not sure what you are dealing with. The water level in the well dropped a lot? Well guy seems to think not. The pump is failing? Well guys would usually pick up on that.

I was wondering if turning the pressure switch down to 30/50, and adjusting the well precharge down would do it. That idea does not seem compatible with the water pressure dropping to zero while you are not using water.

I am not a pro.

 

When I first got home and noticed there was no water, and the pressure tank was at “0”, I also noticed that the pump was running (yet wasn’t putting any water into the tank). I had no faucets on or anything asking for water. Since I didn’t want to run the risk of burning out my pump with no water, I decided to just turn it off.

I left the pump off overnight, and then turned it back on. I immediately noticed water being fed into the pressure tank, and it reached full cut out at 60psi. If I leave it as is and take a shower, and use water sparingly throughout the day, the tank will drop to “0” at some point. On rare occasions, once it gets to the 40psi cut in, the pump will kick on and try to fill it to 60psi cut out. Sometimes it has enough water to reach cut out, but oftentimes it can’t. With enough water used, it eventually gets to cut in, and then drops back to “0”. I tried to run a manual backwash, and it only made it about halfway through the cycle before it ran out of water.

The only temporary cure to this problem is to leave the pump off until I need to use water, and then turn it on and hope it fills the tank. But even then I only get a limited supply of water. I wish I could know what may have caused this to all happen when I was out of town and the backwash was cycling every night?

 

It sounds to me as if the level of the aquifer has dropped. Your pump guy might be able to lower the pump.

There may be some other explanation.

 

Thanks! Being this is my first time on a well system, do pumps need to occasionally be lowered due to aquifers dropping? It’s been a dry year here, so I wasn’t sure if that may have something to do with it? It seems like my pump is working...at least when it has water to pump. I assumed my aquifer was maybe just trying to slowly replenish, since it actually provides a little water when the pump is left off for a while, and then turned back on.

 

If the well were running dry, Eric, I think you would have noticed significant air in the water.

If there is maybe 50 PSI and you stop using water and you turn off the pump, what happens to the water pressure?

If you say it stays above 40, do you have an an above-ground check valve? If you don't know, show us photos of the piping from the well to the pressure tank and gauge.

 

Thanks valveman. When the well guy came over, he measured the amps, said they were normal, and told me “either the backwash system depleted your well, or you’ve got a leak somewhere. Good luck!”. The guy that installed the chlorinator and backwash system hasn’t returned my call to help solve this problem. I would hope he would stand by his word and work if the chlorinator or backwash system caused this issue. All I know is that I never had any pressure or quantity issues before the installation. Very frustrating!

 

Valveman's hypothesis is quite compatible with "a leak somewhere".

Whether you have a topside check valve would change the symptoms that you would see in the case of a hole near the pump.

 

I do notice air and “gurgling” when I turn the pump back on and open faucets, yet I noticed that before this problem started as well when I turned the pump off and then on.

I’ll turn the pump off when the pressure guage goes below cut in of 40psi, and it’s apparent the pump doesn’t have enough water to fill much if any past that (which is oftentimes the case). I’ve learned the hard way that when it drops below cut in, I have limited water available until it reaches “0”. If, for instance, it’s at 30psi (or any other psi) and I turn the pump off, it tends to just stay at that psi level.

I’ve attached a picture of what was a new check valve that was installed before the “T” into the pressure tank. I’ve been haunted for about 9-months by a series of loud “bangs” that occur at cut out (I won’t even get into that nightmare now!). There was a check valve installed when I bought the home, and a Plumber installed a new one...thinking that would cure the “bangs”/water hammer...yet, it didn’t. The next Plumber was convinced I didn’t need that new check valve, and that it may be causing the water hammer. So, he took it off, and installed the red (“Pex” pipe?) that you also see in the picture. Unfortunately, that didn’t work either. So I currently do not have an above ground check valve. Some have said I need it, some have said I don’t

Needless to say, I’ve very confused!

 

Cut in at 40? And then the pressure can hold at 30 for an extended period? That implies that your precharge is set low.

And since you now have no above-ground check valve, and can hold 40 or 30 PSI with the pump off when no water is being used, that implies no hole in the pipe. The exception would be if you have an extra check valve in the well or the hole is between the pump and the check valve in the well.

So review the symptoms. They just don't seem consistent with any simple explanation.

Here is my thought for what to try next. Turn the pressure switch to 30/50 from 40/60. To do that, you would turn the nut on the big spring about 3.5 turns CCW. Then with zero water pressure, set the air precharge to 28. See if things get better or not. If you are running out of water, expect not.

So to be clear, dropping the cut-in and cut-out pressures is not the solution to your symptoms. But it is easy, and while it may not help, it was not hard or costly.

If you are getting air as you run out of water, ask your well guy about the possibility of lowering the pump. Typically, a pump might be set to 20 ft from the bottom. That allows space for sediment to settle and not get sucked up into the pump. If the well water level drops, you might drop the pump to 10 ft from the bottom, and accept more sediment as the downside.

The 20 and 10 are typical type numbers. Your situation may vary.

If you are getting significant air timed to after you run out of water, that sure seems to say the water level in the well dropped to the pump intake level.

 

Thanks SO much for the reply and explanation! So if I understand correctly, since I can shut off the pump and hold the current psi (I usually shut the pump off at any psi below the cut in of 40psi) that implies that this may not be a leak, or hole in the pipe? If I DID have a leak/hole, that water would all drain out to “0”, versus being held at the current psi?

Also, I wasn’t sure if this could be an issue, but the last time I checked the pressure tank air gauge, it was right around 38psi. As I understand it, the air pressure inside the tank should be about 2psi below the cut in? (mine is 40psi). I checked it again when this water pressure issue happened a week ago, and it was at 35psi. I tried to inflate it up (with a bicycle time pump) but couldn’t seem to get any air in to get it up to 38psi. Would being 5psi under the 40psi cut in be part of the problem?

I also noticed that the time from cut in to cut out has increased quite a bit from what it was before this water pressure issue came about. From 40psi to 60psi, it used to be a steady 38 seconds (with the ever annoying series of “bangs” occurring at 60psi cut out). Since this started, that time is now a minimum of 1.5 minutes, and can go upwards of 3+ minutes. I assumed with my 2HP pump running properly, that cut in to cut out time should stay consistent?

I’ll try to adjust the pressure to 30/50 as you suggested to see what happens. I assume I need to find the pressure switch breaker, turn it off, and then start adjusting?

Thanks once again!

 

No leak above the last check valve, and the check valve would normally be in the pump or just above.

Yes.

Now this is not expected. If you have a 38 air precharge, it seems unlikely that your pressure could sit at 30 or 35... unless the pump was running and something was using a lot of water.

I am shocked that you don't have that breaker memorized.

It would be OK to have the power on as you adjust downward. In fact, if you could have 30 PSI pressure, you could turn CCW until the switch clicked. But you are going to need to turn off the breaker to adjust the precharge.

Sounds like a bad or too-small air pump. It takes a lot more air for the pressure tank than a bicycle tire takes.

Being 5 psi below the cutoff would not cause a symptom, other than being able to maintain 36 for a while. It does stretch the diaphragm a bit more than necessary, but not bad.

20 PSI precharge, still no symptom, but you are stretching the diaphragm even more.

That slow-to-60 is a really good reason to reduce your pump cut-in and cut-out. Maybe 35/55 would be good, but going to 30/50 would be even better to try at this stage I think.

 

Thanks once again. I wish I knew what type of setup I had out in the well (where and how many check valves, etc). I contacted the company that’s listed on the well permit that drilled and installed the well back in ‘95; however, they said they didn’t have detailed records of it.

I’ll adjust the pressure to 30/50 and report back on my findings. Amazing how much detective work is involved in Plumbing!