Weird questions that might be difficult to answer

Old 06-20-18, 12:57 AM
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Weird questions that might be difficult to answer

I've attached a picture of my question.

You can see that the incoming water piping size to my house is 1.5". You see where the relief valve, expansion tank and transducer are. When they reduced the 1.5" pipe to 3/4" pipe. How much volume am I losing from that reduction? I know its such a tiny run, but you can see where the bladder is, having to go through .75" reduction and then having the water have to turn from the cross, and go into the pipe. Would upgrading it all to 1.5" help with supplying volume to my bladder any faster? Also, you can see in the picture. Would it be a better idea to put my bladder on top of the cross, and put the transducer where my bladder is? Could upgrading the 3/4" piping to 1.5" and moving the bladder on top of the cross help?

The reason when I ask is, because when I have my irrigation on and there is a big demand for instant water. My bladder can't fill fast enough because of the pressure drop and it causes my bladder to slam down and cause a water hammer in my house.

I know the solution to that problem is, lower the demand on the irrigation ( which I can't do at all ) or increase the pump size.

But my question still stands, would moving the bladder to the top of the cross, and moving my transducer to the bladders original location, and increasing the piping size help with filling the tank faster than its currently being filled when theres a pressure drop?

Its a VFD system, not a CVS. I understand the pressure tank is a shock absorber. According to the manufacturer. a 40-45GPM system should be using a 9 gallon tank. The one I have is 4.4 gallon. It definitely need more shock absorber.

Do you think upgrading to a 10.3 gallon tank, and increasing my piping size to the bladder help my problem?

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Last edited by PJmax; 06-21-18 at 12:02 PM. Reason: enlarged picture
Old 06-20-18, 01:10 AM
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Pipe diameter and relation to flow are simple to determine if you recall the radius squared times pi gives you the cross sectional area. Hence, cutting the diameter in half results in the area being cut to a fourth of the original:

(1/2) = 1/4
Old 06-20-18, 01:29 AM
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So even thought I am going from 1.5 to 3/4" I am actually reducing the flow by 1/4? That definitely could be one of the reasons why the tank can't refill as fast as it should.
Old 06-20-18, 02:33 AM
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You aren't reducing it by 1/4. 1/4 is all that is left. You are reducing it by 3/4!
Old 06-20-18, 04:06 AM
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Inlet to tank is still 3/4. moving it would not help. Put a water hammer in the line close to pump. Something like this. Bigger tank if the inlet is 1 1/4 or bigger.
Old 06-20-18, 08:34 PM
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Doing anything to the piping above the copper tee is an exercise in futility as there is NO flow in this piping unless the relief valve is opening.

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