aerator hammer pump cycling???'s

[Jaws]

Usually I can lurk around here and find my answers. I think I know the answer to this question but I would like to make sure.

location florida

deep well is 220' with a submersible pump feeding into a bladder tank everything works here. I left two ball valves one 1" for the house and the other 1 1/4" for possible future irrigation needs. These both feed from the main well and bladder tank.

Slight hint of Sulfur so I installed an aerator. From the house feed (the 1" off of the main well I feed to the aerator.) No problems

From the aerator I feed through 1" piping through a ball valve into a checkvalve, into a quick disconnect, and finally into the inlet on the aerator jet pump. This pump is mounted on top of an additional bladder tank this piping configuration is about 4 feet of pipe to the ball valve then 6" to the check, 6" to quick disconnect then 1' to the inlet.

From the outlet on the (aerator) jet pump I feed to ground level and tee off to the house and the bladder tank...all in all about 4 foot of piping (my main feed line for house only using aerated water 1" piping.) A few feet downline I have another ball valve to shut off the feed to the entire house. The piping then runs about 120' to the house.

The pressure switch is preset to 22 and 38 I have decreased air in the tank to about 20. I've made no further adjustments although I will probably eventually fiddle with the pressure switch to spread it out and increase pressure. The bladder tank is not water-logged and is brand new. The reading on the pressure guage at shut off is 40 and immediatly falls to the 38. At this time the reading on the tank is 36 (maybe just a difference in guage readings???)

The problem is I have developed water hammer at the check valve going into the jet pump. The second problem is that the jet pump is cycling repeatedly hammering the points back and forth. At first I thought the tank was bad I checked it and now believe it is ok.

My question is I turned the ball valve that is located before the check valve half way off and noticed a significant decrease in the amount of hammer and the pump stopped cycling. If I was to put an air chamber in the line just before the check valve, on the aerator side would that fix my problems? If I tee'd off of the vertical line as it exits the aerator and then elbowed up 1 foot to form an air chamber would that fix the problem or would the water being allowed to run horizontal for a few inches and mess it up. What about a mecanical studor vent : )

Any suggestions???????? Thanks

 

[Gary Slusser]

This aerator is fed from the well pump and holds water at atmospheric pressure right; meaning the aerator is not pressurized? Your shut off valve and then this check valve is on the outlet of the aerator tank right?

If so, you have flooded suction to the jet pump and the water level in the aerator tank is probably higher than the jet pump, right?

At the lowest water level in the aerator, if the pump inlet pipe is still lower your'e fine, if the water level is lower than the pump's inlet pipe, you need a foot valve in the aeartor on the end of the pump's suction line.

If the water level is always up to the pump's inlet height, remove the check valve and put it on the outlet of the pump before the pressure tank. The pump will keep prime as long as the water in the aeartor is as high as the pump's inlet pipe and the check valve on the outlet will prevent the pressure tank from bleeding back through the pump into the aerator causing cycling of the pump on/off.

I don't like a pressure tank to be plumbed on a tee before the tank inlet. I like to go past the tank, feeding the tank off the main line to the house. That way the water flow direction does not have to change direction when the pump comes on or goes off, which causes water hammer when it does like in your design.

I would not build or use any type of hammer arrestor, that treats the symptom rather than the cause and an air chamber type will allow the air to be absorbed into the water and that prevents it from working. Then you drain the water out of the system to get air back into the chamber; over and over'n over for ever.

You should set the air pressure in the pressure tank to 28 psi with no water in the tank and then adjust the switch to 30/50.

How do you control the water level in the aerator and the well pump?

 

[Sponsor]

 

[Jaws]

This aerator is fed from the well pump and holds water at atmospheric pressure right; meaning the aerator is not pressurized? Your shut off valve and then this check valve is on the outlet of the aerator tank right?

1. yes
2. yes the valves are on the outlet side


If so, you have flooded suction to the jet pump and the water level in the aerator tank is probably higher than the jet pump, right?

I believe that the water level in the aerator and the inlet to the jet pump are pretty close to equal, I'll have to check to be sure. I brought the outlet pipe up, then horizontal through the tank then back down about 6" on the outside of the tank to get it in line with the inlet on the jet pump, then horizontal to the the jet pump. I flooded the aerator when I primed the pump to force the air trapped above the normal water level out of the jet pump's vent; because this u-shape is above the aerator's water level and jet pump's inlet.

At the lowest water level in the aerator, if the pump inlet pipe is still lower your'e fine, if the water level is lower than the pump's inlet pipe, you need a foot valve in the aeartor on the end of the pump's suction line.

??????I have the outlet pipe/suction line to my jet pump terminate about 8" above the bottom of the aerator. This is my suction line. If I understand correctly you recommend a foot valve in this pipe right?

If the water level is always up to the pump's inlet height, remove the check valve and put it on the outlet of the pump before the pressure tank. The pump will keep prime as long as the water in the aeartor is as high as the pump's inlet pipe and the check valve on the outlet will prevent the pressure tank from bleeding back through the pump into the aerator causing cycling of the pump on/off.

will I need an additional check valve here, I'm not sure air pressure won't force the water from my pump back into the aerator if I remove that valve. Doesn't the u-shape I created in the suction line assure part of the pipe will always be above the water level in the aerator and as the aerator's water level decreases wouldn't the jet pump/bladder tank spend a lot of time backfeeding to equalize pressure up to the height of the inlet on the jet pump, until the well pump caught up?

I don't like a pressure tank to be plumbed on a tee before the tank inlet. I like to go past the tank, feeding the tank off the main line to the house. That way the water flow direction does not have to change direction when the pump comes on or goes off, which causes water hammer when it does like in your design.

The outlet from the jet pump comes out of the top of the pump, turns vertical, then it runs down into the center leg on the tee...Are you saying to cut out that tee and place the house feed on the center leg of a new tee that way the water will flow one direction and branch off to the house or continue in a straight line to the tank as it chooses. Will this solve the problem?

I would not build or use any type of hammer arrestor, that treats the symptom rather than the cause and an air chamber type will allow the air to be absorbed into the water and that prevents it from working. Then you drain the water out of the system to get air back into the chamber; over and over'n over for ever.

ok

You should set the air pressure in the pressure tank to 28 psi with no water in the tank and then adjust the switch to 30/50.

Thanks

How do you control the water level in the aerator and the well pump?

with a 3/4 valve attached to a chunk of styrofoam that rises with the water level to eventually cut off the feed. It came with the aerator. they didn't have a 1" valve so this is a point of restriction but I figured it really wouldn't matter as it would just feed the sprinkler heads on the aerator with a little less volume???

You took a lot of time in your detailed answers and I really appreciate it. I agree with you and would rather fix the problem than treat the symptom...if another check valve and a foot valve will make this work smoother no problem. Thank you.

 

[Speedbump]

You have too many things in your suction line. No ball valves should be there nor quick disconnects. Just the absolute necessary fittings to get the pipe from the footvalve in the aerator to the pumps suction inlet. No check valve either. Footvalve only. Make sure the pressure switch is within a few feet of the pressure tank. This check valve you have wouldn't be the non spring loaded type would it? If so, that is your water hammer problem. Remember, only a footvalve in the aerator and be sure it's brass not plastic.

I don't agree with Gary's check valve on the outlet side of the pump either.

bob...

 

[Jaws]

Thanks it looks like the consensus is definitly no check valve, or other things, in the suction line and add a foot valve (brass) I'll try that. I appreciate it.

I believe that the check valve is spring loaded , It is the <$10 PVC one Lowe's carries...it was recommended to me by a pump guy instead of a foot valve.

 

[Gary Slusser]

Yes, since you don't have the aerator tank bottom feeding the pump, you don't have flooded suction so, you need a foot valve in the aerator, no shut off valve o check valves between the aerator and pump and no check valve between the pump and the pressure tank.

You would have needed the check valve at the pressure tank if you had the aerator tank feeding from its bottom and the pump on the ground or slightly above ground level and no foot valve or the pump would have constantly been cycling on/off as the pressure tank backfed through the pump into the aerator tank because of no foot valve on the pump's inlet pipe.

Your 3/4" float valve shouldn't be letting water through it into the aerator because that is not providing much aeration IMO. Do you have a safety low water in the aerator tank means to shut off the jet pump from running dry? If not I'd add one.

 

[Jaws]

Your 3/4" float valve shouldn't be letting water through it into the aerator because that is not providing much aeration IMO. Do you have a safety low water in the aerator tank means to shut off the jet pump from running dry? If not I'd add one.

I'm not sure I understand my float valve controls the on and off of the aerators sprinkler heads The water only passes through it when open and hten it is enclosed in pipes until it reaches the heads and sprays out. When you say "Your 3/4" float valve shouldn't be letting water through it into the aerator" did you misunderstand me to say that the valve feeds directly to the aerator without passing through the sprinkler heads?

Great suggestion on the safety low water cut off I was wondering how to prevent the pump from pumping dry as it seems to out pump my main well.

These Cycle Stop valve you guys talk about would they be any benefit to me?

Thanks again

 

[Speedbump]

These Cycle Stop valve you guys talk about would they be any benefit to me?

That would depend on your jet pump. If it's strong enough to hold 40 psi or better while your using water, then yes. If it loses pressure below 40 psi when your using an average amount of water, then it wouldn't be much help.

bob...

 

[Gary Slusser]

I'm not sure I understand my float valve controls the on and off of the aerators sprinkler heads The water only passes through it when open and hten it is enclosed in pipes until it reaches the heads and sprays out. When you say "Your 3/4" float valve shouldn't be letting water through it into the aerator" did you misunderstand me to say that the valve feeds directly to the aerator without passing through the sprinkler heads? These Cycle Stop valve you guys talk about would they be any benefit to me?

The heads should be fine spray heads, not sprinklers. I read a 3/4" flow into the aerator tank in addition to the spray head's flow.

I think because of the holiday lay off Bob has the CSV thing backwards, ... if your repressurization jet pump shuts off during water use, then a CSV is a good idea because it will greatly reduce cycling of the pump and give you constant pressure. If the pump keeps running during water use then you wouldn't gain much with a CSV.

 

[Speedbump]

I think because of the holiday lay off Bob has the CSV thing backwards, ...

I thought that was what I said. If the pump won't keep up with water usage, a CSV won't help.

bob...

 

[Gary Slusser]

Yeah it is, I read and reread that and thought it was backerds, I need a layoff.

 

[Speedbump]

Take a week off and call me in the morning!

Dr. bob...