Weak Water Pressure Diagnostic FAQs

Q&A about bad water pressure #4

Poor Water Pressure Only at Certain Fixtures Q&A

Weak sink water pressure after installing a new shutoff valve

A shut off valve was installed under the sink and now the water pressure is very low. What would cause this? On 2015-08-11 by Anonymous

Explanation by (mod) -

Anon

A valve that is partly closed

A valve that was installed using too much solder - solder flowed into and blocked the valve or pipe

A valve whose design restricts water flow

Crud in the piping caused during the valve installation has clogged a sink strainer

Why is water pressure good in some areas and bad in others after I worked on my plumbing?

Earlier today I had to cap off an outdoor hose bib pipe that broke off under ground. Pretty straightforward. More digging will be required to replace the hose bib, but it's capped.

After I turned the water back on at the meter, had some very odd and sporadic water pressure issues. I will describe them in inline order first to last.

Next in line hose bib, had good water pressure that dwindles after it has been on for a few minutes. I think there might be a Tee here that feeds the house and goes out to another hose bib.
Third in line hose bib, (end of the line outdoors) great water pressure. (Possibly it doesn't feed from that line, but I didn't dig to find out. It looks like it would from the placement of it.

In the house, laundry room, great water pressure.

Shower, great water pressure. (hot and cold)

On the outside wall from here is another hose bib that had almost no water pressure, until I disconnected the hose that was on there, and now it is fine.

Toilet. weak water pressure.

Bathroom sink. Almost no water pressure. Trickle (Both hot and cold)

Here's where it gets baffling.

Kitchen sink. Good hot water pressure (not as good as it used to be, but that was previously almost too strong), so-so cold water pressure. Kitchen sink is end of the line.

I checked the leak detector on the water meter and it was not spinning, but jumped a couple of times, like there was a momentary leak.

My plan is to monitor the water meter over night to determine if I do have a leak.

Thinking maybe sediment got in the line from the underground break and is clogging stuff up, but not sure how to flush it all out.

Wondering if the bathroom faucet would suddenly and coincidentally have gone bad, but that doesn't explain the toilet. If sediment was in the line there in the bathroom, then I would think the kitchen sink would also be slowed to a trickle?

(Stumped) Also concerned now about my water heater getting sediment in it, but for the moment it seems ok.

Your insight is appreciated. On 2018-02-28 by bugnutz

Diagnostic and repair tip by (mod) - debris from plumbing work can clog fixture strainers or shower heads or toilet fill valves

Bug

When water pressure is good in some areas and bad or inconsistent at others I figure it's not a pump or well problem.

If it were the pump or well you'd see the same issue everywhere (though of course a fixture that runs more water faster will behave a bit differently that one that uses less water or runs water more slowly).

When you work on plumging pipes it's not uncommon for debris to get sent through the lines to where it may clog a faucet strainer or shower head - and of course just which fixture gets clogged might be the fixture that had the bad luck to be tested first.

Try this fix first:

un-screw and clean out the debris-clogged faucet strainers first; let me know how that works.

You may need to do the same thing to shower heads, and sometimes we also find a toilet fill valve that's mineral scale or silt clogged as well. - DF

How come water pressure is fine everywhere except my kitchen sink?

I m staying ground floor, and the pump is fixed just behind my kitchen. the pressure of the water is ok in all the points except in the kitchen sink On 2016-03-18 by mrs.chuttoo

Answer by (mod) -

Mrs. Chut: try removing the sink faucet strainer; if pressure is good, clean or replace the strainer.

Why is water pressure less when water runs through the water softener?

i have a eco water softener and the pressure out of it is less than if i by pass the softener. ? On 2017-09-26 by Mike

by (mod) - water pressure is reduced when the water softener is not in bypass mode

Mike,

That sounds as if you're seeing too much pressure drop across the water softener, right? Or is it a problem? How much pressure drop?

If the pressure drop is slight then it may be the normal effect of the added flow resistance of sending water through the softener control head and resin tank.

But if the pressure drop is notable, and if this is a recent problem, then it's possible that your softener needs a resin change or that its control valve is not open fully.

Weak water pressure unless we put the water softener in bypass mode

The water pressure is good when the conditioner is bypassed. When the unit is working or connected the preasure reduces. On 2016-01-18 by Robert Gilmartin

by (mod) -

I suspect a clog in the water softener control head or less likely, need for media replacement in the resin tank.

Water Pressure Problems During or After Freezing Temperatures

No water after water pipes froze

Single line jet pump, private country well.

After I spent an unexpected nite in the hospital recently I had no heat source on for about 16 hours.

Household lines, pump and main supply line coming thru the foundation froze, unthawed frozen lines turned pump on and it runs fine just no water, I primed it twice... is it a broken internal piece ? Thanks On 2017-03-19 by GuyWithNoWater

by (mod) -

When I've seen this problem often a section of well piping was still frozen.

Or your well foot valve or check valve is bad, allowing loss of pump prior prime.

That is, IF your pump is an above ground jet pump

See our article: WATER PUMP PRIMING PROCEDURE

No water pressure after freezing weather

I only had hot water coming well had two plumber out two different answers now have no water at all but we had very cold weather, now we have no water all and I dont know what to do. On 2017-01-14 by marca

by (mod) - water line freezing problems & solutions

Marca

I can't diagnose this from your e-text, but I suspect there's a frozen water line. The fact that you had hot water but no cold is often a clue that supply pipes are starting to freeze. Some plumbers are good at finding and thawing frozen pipes but until you find and fix the cold spot you'll have the problem again.

See PIPE FREEZE-UP POINTS  for help finding where the pipes are frozen

If the freeze-up is at a location you can access and if it's not too extensive you might get water going again by simply using a hair blow-dryer to warm the pipe.

See PIPE FREEZE PROTECTION - home - for our articles on how to avoid frozen pipes in the future.

No water after I installed a more powerful water pump

My well pump went out; I changed it from half to 3/4 horse and the new pump ran great for a while, but then I lost all water.

I changed bladder tank pressure switch cleaned water softner and changed filter have water low pressure pump kicks on at 42 and shuts off at 62. I don't know what it might be - please help. On 2016-11-22 21:27:49.626873 by mike

Diagnostic suggestions by (mod) -

Mike: do you think that your larger pump was thus delivering more water faster and so it exceeded the well flow rate?

That could be what killed the prior pump too.

This is perhaps the most common case we find when folks install a bigger water pump.

A modest or poor well flow rate may not have shown up as a problem with the old pump because it drew water out of the well more slowly.

But when a newer, higher capacity water pump is installed water is removed from the well more quickly, exhausting the well.

After changing a water pump we may see total loss of water pressure because

• The well has a poor flow rate and needs time to recover.
  
  If the well has a large static head (water stored in the well bore itself) but a very poor flow rate (rate at which water enters the well bore from the surrounding aquifer) then you might see good water flow initially as you're drawing on the water reserve in the well bore (the static head), but once that's exhausted a pump can't deliver water faster than water is entering the well bore (the well's flow rate).
  
  See WELL FLOW RATE, and if this is your problem you'll also want to read WELL YIELD IMPROVEMENT
  
  And to understand more about the well's static head see WELL DYNAMIC HEAD & STATIC HEAD DEFINITION
• There may be a pump protection device that shuts off the pump
  
  to protect it from running dry - explained at WATER PUMP PROTECTION SWITCH - some of these switches must be re-set manually.
  
  Other low flow rate wells may use a tailpiece installed at the water pick up in the well to protect the pump, explained at WELL PIPING TAIL PIECE
• The pump may have been damaged:
  
  If there is no pump protection device, the pump ran dry and has been damaged.
  
  See this DIAGNOSTIC TABLE for WATER PUMPS

After installing new well pump we run out of water

Just put down a new well pump. When we changed pumps, we increased it from 1/2 horse to 1 horse because it is 85 ft. deep. ( recommend by the well man ).

We have had this well over 10 yrs. never had great pressure but always had water. Now our water runs for about 1 hour then loses pressure, down to a trickle.

My tank seems to be holding pressure at 40/60. What is going on? On 2016-07-21 by Lwquin

by (mod) -

LW

Just a guess, but it's pretty common to run in to this when we add a more powerful pump to an existing, low-flow-rate well. The amount of water available to your pump is not the 85 ft. well - but the combination of the actual depth of water inside the well that the pump can reach (since water doesn't come to the top of the ground nor the pump reach the very bottom of the well, PLUS the well flow rate - at which water runs into the well while you're taking water out.

An older slower-pumping pump may not have exceeded the flow rate, while the newer one does.
Also FYI the flow rate is not a constant number - it often diminishes over pumping time as you exhaust the water in the rock immediately around the well.

SO, you are probably running the well dry. Ask your installer about adding a pump protection switch and/or a well tailpiece that will at least protect from running the pump dry - which will ruin it.

Search InspectApedia for these article names to read details: WELL WATER QUANTITY, WELL STATIC HEAD, WELL FLOW RATE, HOW to INCREASE WELL WATER QUANTITY