Pressure drops and low water flow at home

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clif

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Location
, LA
Hi.
I'm not a plumber, but understand how many things work. I'm an operator for a chemical plant, and operate a variety of pumps, etc. just to give an insight on me.

At my new home - my water pressure is about 60 psi with all faucets etc. closed at the nearest spigot to the water meter.

I have a water softener installed for the whole house. It's rated for over 12 gpm I believe, more than what I can get at the house with every faucet open.
Best GPM flow rate I can get is around 5.5 gpm with several faucets opened simultaneously. That being said, I bypassed the softener all together and get the same pressure drop when more than one faucet etc is opened.

If I run my master bathtub faucet (which has a larger line run for it I think) it gets good flow - but it drops the line pressure I think to 40 psi. And if any other faucet etc is opened the line pressure drops to something useless like 15-20 psi. The main bathtub faucet running will cause any other line to drop to a useless trickle almost.

Had the water dept. check out their stuff they claimed they were fine line size, pressure at the meter etc.

Had the plumber who did the plumbing for my house check out everything and they claimed their work was fine, and that the problem is the water dept not supplying enough water.

Water dept. claims that "in the summer people wash their cars, fill pools etc and this is why the water pressure is bad" except now it's the winter and the problem is the same, which I expected.

Is there a solution to this problem that I can do?

I've read about water booster pumps being install at home, and in many cases this fixes the issue. BUT I don't want to spend $1500 on a system and another $500 for labor just for the set up to not work b/c the water supply coming in can't keep up with a 12-20 gpm 70psi pump setup.
I was really interested in one of the VFD type pumps, like a goulds.

I'd like to have at least double the flow rate, I'm fine with ~60 psi just need it to stay there when more than one line is open.

Water sprinklers I can only run one at a time, if two are used at the same time, they both spray out like limp noodles! Ridiculous. My last home a few miles away from here (and on a different water system) I could run 3 sprinklers as good as this runs one.

Any suggestions?
 
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You don't have a pressure problem you have a volume problem. What type piping do you have, copper PEX or galvanized? What size are the water line in the home? I am assuming the main entering the home is at least 3/4".
 
You don't have a pressure problem you have a volume problem. What type piping do you have, copper PEX or galvanized? What size are the water line in the home? I am assuming the main entering the home is at least 3/4".

PEX (it's the plastic stuff - red and blue colored if that's what it's called)
I'm pretty certain they ran 3/4" line to the home and that's also what the plumber assured me it was.

Is there anything I can do to increase the volume? Would it even help to add a booster pump or would the pump just cavitate and starve for water in the suction line?

Would it make more sense to run a 1" line vs. the 3/4" one that's there? Won't be easy it's run under a sidewalk but it's only like 50 feet or so from the meter to the house...

Some in the home are 1/2" and some are 3/4". Would assume they ran a 3/4" "header" and tapped off it with 1/2" lines. Might be worth getting a different plumber come in and check it all out to make sure nothing was missed.

Just FYI in case this is important, my home is 2251 square feet living, 2 1/2 baths.
 
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Pex pipe has a smaller ID then copper so it is important to not have two major fixtures on a 1/2' line.
The mains throughout the house should be 3/4" with 1/2" branches to each fixture. If the main entering the house is pex and also being used for a irrigation system it should be 1".
 
Pex pipe has a smaller ID then copper so it is important to not have two major fixtures on a 1/2' line.
The mains throughout the house should be 3/4" with 1/2" branches to each fixture. If the main entering the house is pex and also being used for a irrigation system it should be 1".

The main 3/4" line to the house is PEX.....
Think if I changed this to a 1" size PEX line it would make a significant flow increase?
I'm thinking about changing the main shut off valve at the house to a full port valve (I think the one there now isn't).
 
Thanks for the help, I'll contact a local plumber about possibly changing the line to 1" for me. Wish they'd put that size in in the first place.
 
Could be pressure regulator but the more fixture u turn on the volume u will get turn ur presure regulator up most r pre set around 48 to 50 ponuds try adjusting it to 70 that will let more flow though it lol
 
As John said, it sounds like a volume issue, but I feel that I should add that if this is a newer house and the problem has existed for a while that there could also be a kink in the service line. I have seen this severe pressure drop many times on new construction homes with copper and plastic water services.
Increasing the size is the way to go, just be sure that the service is properly backfilled with (preferred) sand to protect the pipe on the bottom, sides and about 4" on top. Crushing and kinking is becoming more common due to hasty installs to save money. Even the existing soil as backfill could settle and cause deformities in the plastic, more so than copper, and a base of sand would give better compaction and stability until all fill has settled.
If you have the old service replaced, please follow up with us if you discover that there was an obvious problem. The information would be useful to others who visit the forum as this is a frequently seen problem.
 
If u got a 5/8 or 3/4 meter it will only give u that much flow allowed by the meter u may get more volume for a second or 2 by increasing the pipe but thats about it not worth the cost of a line replacement unless ur line is smaller than ur meter size
 
If u got a 5/8 or 3/4 meter it will only give u that much flow allowed by the meter u may get more volume for a second or 2 by increasing the pipe but thats about it not worth the cost of a line replacement unless ur line is smaller than ur meter size

If that were true then the water mains with 5/8"meters would only need to have 1/2" copper lines.
 
Could be pressure regulator but the more fixture u turn on the volume u will get turn ur presure regulator up most r pre set around 48 to 50 ponuds try adjusting it to 70 that will let more flow though it lol

Never saw a regulator inline from the meter to my house when they put it in. 60 psi must be what the main line runs at.
 
As John said, it sounds like a volume issue, but I feel that I should add that if this is a newer house and the problem has existed for a while that there could also be a kink in the service line. I have seen this severe pressure drop many times on new construction homes with copper and plastic water services.
Increasing the size is the way to go, just be sure that the service is properly backfilled with (preferred) sand to protect the pipe on the bottom, sides and about 4" on top. Crushing and kinking is becoming more common due to hasty installs to save money. Even the existing soil as backfill could settle and cause deformities in the plastic, more so than copper, and a base of sand would give better compaction and stability until all fill has settled.
If you have the old service replaced, please follow up with us if you discover that there was an obvious problem. The information would be useful to others who visit the forum as this is a frequently seen problem.

This is good stuff to know, wish I knew half this much when the house was being built. Would have ensured the sand was underneath as I think they just set it on the soil that was there, which is clay type very hard.
And would have demanded the 1" service line, never seen PEX before at all since my last home they used all copper. wish I knew that the inside diameter was smaller. You'd think the plumber doing my house would have done all this from the start, but as was said some guys do the cheap way out on a job.
If I ever get this resolved I'll certainly post my findings here. I know first hand how frustrating this is and anyone else may be dealing with the same issue.
 
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Where I live in alabama our meters r 5/8 mostly we use 3/4 main to the house 3/4 cpvc or pex (some copper but price of copper) has slowed its use to nearly nothing lol as main supply 1/2 branch to fixture shut off the 3/8 od lines feed the fixtures except tubs, washer so on if I understood what ur saying I ur pressure drops to much and volume decresses way down u could have a screen in ur regulator almost stopped up or a diafram in the regulator also the backflow may not b opening up properly but 15 to 20psi loss isnt to bad loss with an open fixture try going to a nabors house see how his loss is before and after opening a fixture
 
Where I live in alabama our meters r 5/8 mostly we use 3/4 main to the house 3/4 cpvc or pex (some copper but price of copper) has slowed its use to nearly nothing lol as main supply 1/2 branch to fixture shut off the 3/8 od lines feed the fixtures except tubs, washer so on if I understood what ur saying I ur pressure drops to much and volume decresses way down u could have a screen in ur regulator almost stopped up or a diafram in the regulator also the backflow may not b opening up properly but 15 to 20psi loss isnt to bad loss with an open fixture try going to a nabors house see how his loss is before and after opening a fixture

No regulator is inline.
Just FYI its all new plumbing on a new house.
 
What would really tell me something is if someone knew the flow rate I should be getting under ideal conditions with 60psi pressure from the water department's supply going through the 3/4" PEX feeder line to my house.
Most I can get is ~5.5gpm according to the flow meter on my water softener.
This would tell me if there really is a kink or obstruction somewhere or just the line can't flow more than 5.5 gpm @ 60psi.
I've found many calculators online to help me figure this out but most I've seen are very confusing and want more input data than I know.
There should be a simple estimator like:
line size
psi
water
=
flow rate
 
You are forgetting many variables, such as length, bends, and head heights...to name a few. It all adds resistance.

That's true forgot about that.

The path from the meter to the house is a straight shot minus whatever bends and connections they made to hook up to it. Do plumbers normally carry flow meters on them? I could have one check my flow at the spigot where the water comes in the house....
 
Does anyone know how to help me identify if the 3/4" soldered globe valve they used as my main cut off valve is a fully ported valve? If there even is such a thing? Seems like if the one I have isn't and was changed out to a full port valve I would increase my flow even if its just a little. I'd be happy with an additional .5 GPM since I'm not getting good flow overall. It has the little drain cap thing built into the side.
 
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