Plumbing System Q&A set #3Building plumbing system installation, inspection, troubleshooting & repair FAQs set #3.
These plumbing repair articles answer nearly all questions about diagnosing and repairing building plumbing systems, including water supply and drain piping, vent piping, gas and oil piping in buildings, plumbing fixtures, water heaters, water pumps, water pressure, water softeners, water testing, water treatment equipment, water wells, and septic systems.
Also try the page top or bottom SEARCH BOX as a quick way to find information you need.
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These questions & answers about building plumbing systems were posted originally
at PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR - please be sure to review that article
On 2020-02-16 by tommy cook
what style of toilets are the ones used in jails stainless steel tankless toilet sink combos. Need to know how it works so I can fix flushing problem.
On 2020-02-16 - by (mod) - prison type sink-toilet clog repair
Tommy,
Prison toilets generally work like other toilets but are constructed of stainless steel and may use a power flush or gravity flush system. Shown here is a Kuge brand gravity-flush stainless steel toilet.
If your toilet has a flushing problem start by plunging it vigorously with a toilet plunger.
See details at TOILET CLOG REPAIR, UN-BLOCK
On 2020-01-21 by johnboy683
Lampwick ok ? on fuel oil threads, with dope of course.
Old plumber , John
On 2020-01-21 - by (mod) -
John
You should not need to add any gasket-type material such as lampwick on heating oil piping threads, though I agree that's an old plumbers trick and I still have a few bits of lead-impregnated string in my box of plumbing washers and gaskets.
I figure if your fitting threads are so worn that just use of a pipe sealant rated for use on oil and gas piping isn't enough to seal the fitting, the the fitting is worn and should be replaced.
Living with a worn threaded fitting jury-rigged with lampwick is actually unsafe in a subtle way: for example vibration allowing air leaks into the system lead to improper burner operation that in turn can lead to a puffback explosion.
On 2020-01-15 by GUY
There was air trapped in the well tank and since it was old i decided to replace it and the water heater that blocked it in.
Now the air coming thru the system is twice as bad.
Tried bleeding whole house but it came right back. I'm thinking check valve at pump? any info would be great...thanks
On 2020-01-15 - by (mod) -
Guy
I'm a bit confused;
It's normal and proper for there to be air in the water pressure tank. With the pump OFF and water pressure drained from the system by opening a tap, the water pressure tank air pre-charge is set to 2 psi below the pump pressure control switch CUT-IN pressure.
For example if your pump control cut-in pressure is at 20 psi, then your air pre charge should be set to 18 psi.
On 2019-04-28 by Anonymous
how to wire a water heater element with dual wattage
On 2019-04-28 9 by (mod) - how to wire a water heater element with dual wattage
See ELECTRIC WATER HEATER ELEMENT REPLACEMENT wiring at
https://inspectapedia.com/plumbing/Electric_Water_Heater_Element_Replacement.php
On 2019-02-08 by Auntie P
I have a problem with frozen drainage pipes to the city manhole. From my clean outs to the manhole, the pipe runs under my driveway and it is suspected by my plumber that because of that the frost sinks lower and freezes the water that has bowed under.
From there to the manhole is another 10-12 feet. I live in northern Wisconsin and the freeze is definitely from my clean outs to the manhole. The crawlspace under my house has been heated and the pipes wrapped in heat tape.
I was thinking that if we can dig down under the pipe I could insulate the pipe with styrofoam. Moving the driveway would be a far more expensive option and require a rebuild of the garage. Would styrofoam be a viable option? Either the solid chunks from packaging or the expanding foam?
On 2019-02-08 by (mod) - problem with frozen drainage pipes
Auntie
Before insulating the pipe I'd have its interior inspected by a sewer camera to see if it's sagging as if-so it needs to be repaired or you're still risking clogs and sewer backups.
You do not normally need to insulate a properly-sloped drain line as it doesn't hold standing water and so won't normally freeze.
On 2019-01-04 by Matt
The sand and dirt that is getting in your grimding pump system cause harm?
On 2019-01-06 by (mod) - sand and dirt that in your frinder pump system causes harm?
Great question, Matt.
While some commecial grinder pumps are specifically designed to tolerate various kinds of solids, others, particularly some low-cost and modest-duty pumps that are sold as grinder pumps may not survive long.
As you'll read, it is typical for a grinder pump model warranty to specifically exclude the effects of sand as well as some other substances that are hard on pumps.
Details are at SEWAGE PUMP DAMAGE & REPAIR
There you'll find links to PDF files giving specifications for a number of sewage pumps.
There in the Zoeller Shark pump manual whose link we provide you will read this warning
This warranty does not apply to and there shall be no warranty for any material or product that has been disassembled without prior approval of Manufacturer, subjected to misuse, misapplication, neglect, alteration, accident or uncontrollable act of nature; that has not been installed, operated or maintained in accordance with Manufacturer's installation instructions; that has been exposed to outside substances including but not limited to the following:sand, gravel, cement, mud, tar, hydrocarbons, hydrocarbon derivatives (oil, gasoline, solvents, etc.), or other abrasive or corrosive substances, wash towels, etc. in all pumping applications.
The warranty set out in the paragraph above is in lieu of all other warranties expressed or implied; and we do not authorize any representative or other person to assume for us any other liability in connection with our products.
For a different view of commercial grinder pumps Here is an example of atypical SEWAGE GRINDER PUMP SYSTEM SPECIFICATIONS [PDF] from a Chattanooga Tennessee government document
The grinder assembly shall consist of a rotating cutter and a stationary cutting ring on the suction side of the impeller so the cutting assembly discharges directing into the impeller inlet. All cutters, both stationary and rotating, shall be made of hardened and ground stainless steel and shall be adjustable externally to maintain proper clearance.The upper cutter and the stationary cutting ring shall be reversible for longer service life. In the absence of reversible cutters, a spare upper cutter and cutting ring shall be furnished with each grinder pump.
The pump-motor shafts shall be supported by permanently oiled upper and lower bearings.Bearings and motors shall be protected from the liquid being pumped by dual mechanical seals consisting of a stationary ceramic seal and two carbon rotating sealing surfaces.
Any water leaking past the lower seal shall be detected by an electric sensing probe mounted in the seal chamber.The probe shall be connected to the alarm light in the control panel.
A pump meeting those specifications might be more tolerant of grit in the wastewater. - retrieved 2019/02/11 original source: www.chattanooga.gov/public-works-files/11316_sewage_grinder_pump_systems.pdf
On 2018-12-25 by Barry
I’m planning on adding a second indirect tank (superstore) for extra capacity. Your HTC manual, figure 7 shows a typical configuration with a storage tank. However that tank has 3 connections. Is that a special tank?
On 2018-12-25 by (mod) -
Barry
Actually if you click to enlarge the HTP SuperStor indirect water heater sketches in our article on INDIRECT FIRED WATER HEATERS https://inspectapedia.com/plumbing/Indirect-Water-Heaters.php
you'll see the standard 4 connections:
- cold water in to the heater
- hot water out of the heater
- heating coil loop supply from the boiler
- heating coil loop return to the boiler
On 2018-12-11 Alan
I have a well and noticed my pressure seems low. I tightened the nut on the pressure switch and it kicked on and the pump starts. But the pressure never goes above 42 psi.
Its a new 30-50 switch. So I stopped the pump and figured maybe the gauge is bad because it was all corroded. I put a new gauge on and started everything back up.
The pressure still wont go above 42psi. The switch is still on and and the pump is running. So I loosened the nut till the switch shuts off. Is the pump itself bad? Is there anyway to check that?
On 2018-12-12 by (mod) - the water pressure never goes above 42 psi. Its a new 30-50 switch
Alan
Please try the InspectApedia website search box just above to findand you'll see our article giving diagnosis and repair procedures.
On 2018-09-26 by Lora
I live in a mobile home. I am having gurgling toilets, showers, and sinks, slow toilets and sinks.
I am to the point of getting on top of the roof to clean out the vent stacks. But, I can access the vent stacks but there is no clean out on the vent stacks. Can I install cleanouts to the vent stacks and avoid roof top?
On 2018-09-26 5 by (mod) - gurgling toilets, showers, and sinks, slow toilets and sinks
Lora
at PLUMBING DRAIN NOISE DIAGNOSIS
we describe the causes and cures of gurgling drains; it would make sense to have a better guess at what's the cause before assuming there is much benefit from climbing onto a roof to try cleaning the vent stacks; that's not usually going to be the cause nor the cure unless something odd happened like a bird or mud-dauber wasps have nested in and clogged the vent.
More likely the drain system is clogged or there is a failing septic systems.
I recommend reading CLOGGED DRAIN DIAGNOSIS & REPAIROn 2018-09-27 by Anonymous
@Lora,
I have printed your diagnosis worksheet and have located a plumbing camera. Success will be within my grasp!
On 2018-09-20 by Anonymous
What are the codes regarding pressure balancing valves in the showers on mobile homes
On 2018-09-24 by (mod) - What are the codes regarding pressure balancing valves in the showers on mobile homes
Anon:
I am not aware of any building code pertaining to balancing pressure in showers on mobile homes or any other home.
But I may have mis-understood your question.
If you are asking about anti-scald valves, used to balance cold and hot water flow so as to keep temperature at the plumbing fixture below scalding burn levels, there are building codes in the U.S. and Canada at state and provincial level that specify the allowable temperatures.
See HOT WATER ANTI-SCALD REGULATIONS at https://inspectapedia.com/plumbing/Hot_Water_Temperature_Laws.php
(Nov 8, 2011) jeannette
when i turn the water on, it has good steady pressure until the pump turns on. when the pump cuts on, it starts sounding like a coffee pot making coffee(sounds stupid, but, the best way to describe). air starts comming out of the line along with water. any clue whats going on?
Reply:Jeannette,
please see our diagnostic suggestions for air discharge at plumbing fixtures at
(Apr 23, 2012) Cliff
we live in the country. Gimli. Our breaker with the pressure pump and delhi does not shut of. It just keeps running. We now have switched the breaker off. We therefore would like to know what could possibly be the problem. Is it the switch?? or loss of pressure in tank? or a water problem.
(May 29, 2012) Anonymous
plumber installed a new toto toilet urine smell coming out of toilet sewer gas smell coming out of pipes under bathroom sink plumber put in new downward vent didn't help either smell what needs to be done?
Reply:
Anon: diagnosing toilet urine and sewer gas smells:
At ODORS IN WATER, CAUSES & CURES you will also find a live link to the more-broad topic:
ODORS GASES SMELLS, DIAGNOSIS & CURE - topic home, where we provide several diagnostic guides to tracking down and curing odors at their source. For the case you describe, and with no other information, I'd start by
1. a thorough deodorizing cleaning of all surfaces around the toilet to eliminate any confusion, then
2. there should be no odors coming out of pipes below a sink - as those pipes should not have any leaks whatsoever, so check or re-make any questionable drain, trap, or similar connections there;
3. make sure you've accurately traced the odor to its source - it could be a bad wax ring seal at the toilet, for example.
(Jan 28, 2013) john
looking at a house for sale and noticed that when they built an addition, the kitchen sink cleanout was not moved and thus now inside the house! is this okay? Fyi I'm in California
Reply:
John,
It is common for plumbing cleanouts to be located inside a building.
(Mar 15, 2013) Dean
Got a leak fixed in my house and the central heating hasn't worked properly since it comes on some days and not on other days can anyone help the plumber hasn't a clue
Reply:
Dean,
Search INspectAPedia for
Air Bound Heat
to see a possible cause and cure for the problem you describe.
(Mar 19, 2013) Rick
I have a well system in my house. Recently have begun to have pressure loss in the system. Ex. If i flush the first floor water closet the sink righf next to it does not have full pressure or volume. This will hapen elseware in the house also.
The pressure tank is a goulds pumps v60, 20 gal. 30/50 pressure settings.
If test the air pressure it is at the reccomended psi. 28/50.
If shake the tank with the punp off and system drained I do here water inside.
It takes about 15 sec. For the level to drop to turn the pump on and about 30 sec for it to recover. I took that data while running the washing machine. Which is right next the tank.
The tank is about 8 yrs old. There is no water or air coming from the shrader valve.
Thoughts?
Reply:
Rick,
Let's try to clear up pressure vs flow. When no water is running, the static pressure, read on a pressure gauge, in your water system will be somewhere between 30 psi (the cut-in pressure) and 50 psi (the cut out pressure on your system).
The flow rate, in gallons per minute that you observe at an individual fixture, depends not just on the system pressure but also the diameters of all of the pipes in the supply circuit. If, for example, water pipes are partly clogged, you'll notice that the flow rate will be reduced.
If we run water fast enough or at enough fixtures such that the well pump runs continuously, then the pressure and flow we will see at those fixtures depends on the piping (diameter, length, number of bends, obstructions, friction losses) and the ability of the pump to send up water at a given pressure and flow rate.
Click on WATER PRESSURE LOSS DIAGNOSIS & REPAIR - home - to read how to diagnose and fix problems with water pressure or flow.
Reader follow up: (Mar 19, 2013) Rick
Well I understand what your saying. I guess my point is that this has just started happening a few weeks ago. I have not changed anything in the system nor had any other issues. With pipes or faucets. My concern is my pressure tank. Confused with the psi being ok but hearing water in it.
Reply:
Rick,
We're not giving up. But to be clear, the pressure tank does not provide much by way of water pressure.
The pressure is provided by the pump or in municipal supply, the pressure in the water mains.
When we see pretty good pressure at a single fixture - say a faucet - and water pressure falls off significantly when a second fixture is running, usually that points to pipe clogging.
But if your complaint came on suddenly it makes sense to look elsewhere - even a partly closed supply valve could explain your observation.
(Mar 12, 2014) Steve O
Hi. My home is about 14 years old and yesterday while I was in the basement I heard what sounds like someone knocking on the wall. This is coming in the vicinity of the drain pipes (PVC) that come from the second floor of the house. This went on for around two hours. A knock here followed by half a dozen a few seconds later.
It eventually quit doing this and did not reoccur until the second half of the day.
Today, the same thing happened but it stopped much quicker. I flushed a toilet in the basement around noon on the opposite side of the basement and now it has started again. What could be causing this? HELP!!!
Reply:
Steve,
Please search InspectApedia (you can use the Search box just above) for
Water Hammer
And check out that diagnostic article.
I suspect that's what's going on at your home.
Water hammer is caused by water moving at velocity through building piping; I've found that banging pipes can get started and then continue for a while as water continues to run somewhere, affected further by the security of pipe supports as vibration can make pipe bang on their mount points as well.
(Sept 9, 2014) Phil Putnam
Is the new "Pex" water line latex free?
Reply:
yes
(Oct 5, 2014) Martha Metter
we had a well company come out and fix a cracked pipe at the head of the well. They said they raised the pump at least 5 feet or more and cut off a section of pipe.
They dropped the pump into the well bottom more than several times. 3 days ago the water in house spewed heavy sediment from every faucet and shower/toilet etc.
Then clogged up everything. I called the well co. back, they came out and told me I need to get a plumber in here to flush out the pipes. How do we get the sediment out of our pipes, and is this the well companies responsibility to pay for the work?
Reply:
Martha,
A plumber will open strainers, remove shower heads, etc. to help flush debris from the system. It might be necessary to partly drain tanks such as a water heater or pressure tank as well, of course change any water filters afterwards.
I can't address the question of who pays for this work as I cannot assess responsibility. Any work on a well, even if nothing unusual happens during the job, might stir up debris from the well bottom.
(Oct 17, 2014) Gfgayle
We live in a suburban home that is furnished by a water plant system. Lately, the water has been coming out very erratically. It comes as though I was turning the faucet on and off very quickly. Can you recommend any corrections?
(Oct 24, 2014) Frances
We have an old restaurant and recently we replaced all the plumbing, but now we have a strong sewage smell in the build and can't seem to find the source. Please help.
(Oct 29, 2014) Terry
When the toilet is flushed water splashes up, appears to be releasing air, out of the bowl sometimes so strong it goes onto the floor?
Reply:
That sounds like a blocked drain
11/11/2014 Ryan
I put in a new jet pump and pressure tank set to its proper settings for the pump and installed a new check valve before the pump. I can't keep pressure at any of my faucettes
Reply:
Ryan check out the water pressure diagnostic procedures beginning at
(Nov 18, 2014) m shabbir said:
The drainage bad smell in office feeling at evening time or at any time
while there is no any toilet and water supply and drainage system.
The office area is 10*10m2 .
(Nov 23, 2014) Paul said:
my parents have a new 1-2 flush toilet and at night it makes a noise like it was just flushed,I think there is air getting in somewhere,please help.Thanks
Reply:
I suspect that the flush valve is leaking slowly into the toilet bowl. Eventually the toilet fill control figures that the cistern or tank is too low and goes through a refill cycle.
(Dec 16, 2014) Bob said:
I have a problem with air in my system..air bubbles in the water, bursts of air, and a pump that hunts when it starts and as it is pressurizing.
The pump shuts off at 55 psi, and then fairly quickly falls back to about 39 psi, and then seems to stop
. The water for the system is pumped out of a lake.
There is a foot valve in the lake, and a check valve at the pump.I have two bladder tanks, but both ring hollow when I tap them. The only other things in the system are a string filter, a carbon filter ,and a UV filter.
I suspect that I am losing pressure back though the check valve and foot valve, but am a little mystified as to why the pressure drops so quickly to about 39 psi, and then basically hangs there.
The pump does not seem to cycle more frequently than it ever did. Any suggestions? Great web site by the way. It helped me understand how to set up my system pressures when I put it in.
Reply:
Bob
Please try the diagnostics at
inspectapedia.com/water/Air_Discharge_at_Faucet.php
and let us know how you succeed
Follow up:
Hello again:After reviewing the different possibilities, I think that the most likely cause is a leak back through the check and foot valves. I changed the pump out last spring but used the same check valve.
The pump that I replaced had some hard deposits in it.
I checked all of the fittings I could think to check and tapped the check valve while the pump was drawing to see if possibly there were loose deposits preventing a good seal. I do the trick I'll try replacing the check valve.
Reply: that sounds reasonable
Follow up:
After a couple of days, the air in the system has decreased.Either I tightened a loose connection or tapping the check valve helped.I'll keep an eye on it for now. there is still some air, but it might still be clearing out. Thanks again for your help and for this site.
Bob
Reply:
Thanks for the feedback. Indeed on water systems I've occasionally found air entering the pressure tank and piping at a slightly-leaky plastic line connection between well and pump; we could see the air showing up as bubbles in the clear plastic that contained the water filter.
On tightening the hose clamps and adding a second clamp at two suspicious fittings the air entry stopped.
23 Feb 2015 Fran said:
Is there a heater for a submersible well pump to prevent line from freezing
Reply:
Fran there are drain-back systems that can prevent the well line from freezing and depending on which well line section is freezing, outdoor (or indoor if it's inside) rated heat tapes might suffice.
We discuss well line freeze protection at
And pump protection devices at
(Mar 5, 2015) Marty said:
I have water leaking from a door frame in my 1st floor apt. There is a bathroom on the 2nd floor directly above mine.
For the past two weeks I have been trying to pinpoint where the water is coming from. It does not show up immediately sometimes it takes a week before water drips from the door frame.
I am trying to isolate by using one thing at a time in the 2nd floor bathroom. My plumber and I are stumped as to where the water is coming from.
We are now ONLY flushing the tiolet to see if that is the source of the water dripping down.
I have also ONLY used the shower/tub to see if the water is coming from when we use the shower/tub. It has been such a mystery to understand where water would be coming from that could seep into a door frame and drip down. Any advice, information, insight, or suggestions.
Reply:
See LEAK TYPES, WATER SUPPLY or DRAIN PIPES
for some suggestions on tracking down just this sort of problem.
Please let me know what you find after talking a look at that article.
(Mar 10, 2015) jackie dunadee said:
I cannot get hot water upstairs ,I get real hot water downstairs with no problem but now with ababy ,I want to bath him in tub upstairs . I have a half bath down with shower and full bath upstairs,any suggestions?
Reply:
Jackie,
If the water never gets hot I suspect that there is a plumbing connection problem.
If there is no water at all I suspect a blockage or a closed valve.
If you find that water ultimately gets hot after running a long time, the solution may be to add insulation to the water pipes.
Don't scald the baby.
On 2016-10-30 by chris cumberland
20 ft.down my well casing water is leaking into casing.looks clean,i plan on pumping it into my home.is this a bad thing ? well is only 40 ft. deep.
On 2016-10-31 by (mod) -
Sounds like a bad idea to me, Chris.
If a well casing is leaking into the well then surface water or runoff is leaking into the well - those waters are virtually always un-sanitary. The right repair is to find and fix the leak into the casing and then to sanitize the well.
On 2016-09-12 by Dave
I replaced a faucet stem (faucet stem part# 2K-3H) and the faucet washers on an American Standard style 2 handle bathroom faucet yesterday
. When I reinstalled the faucet stems and turned on the water, the handle on the hot water side turns but no water comes out until I turn the handle beyond about 1/8th of a turn, and when I turn the water off again, there is a "water hammer" sound that comes from the faucet.
And sometimes the water turns on and off as the handle is rotated while in the on position. What can I do to correct this problem?
On 2016-09-12 by (mod) - no water comes out until I turn the handle beyond about 1/8th of a turn
I think there are a couple of points here, Dave.
1. The 1/4 turn, provided nothing is loose in the assembly, may be simply un-compressing the faucet washer - so it may not be a problem. Just double check that the screw holding the washer in place is snug.
2. Water hammer occurs as a feature of the velocity of water moving through piping along with opening size and thus flow rates. Your repair may have changed the opening size and thus flow rate.
Did you use a replacement washer of the very same size and shape as the original one?Some faucet washers are flat while others have a dome shape; the cone or convex side of the dome faces towards the opening that is to be closed when the valve is closed, or in other words the smaller diameter area of the top of the dome shape will be under the screw securing the washer in place, not against the body of the valve stem.
Washers vary in thickness even when the diameter is the same; you may fix the problem by changing the washer thickness.
Those suggestions pertain particularly if water hammer happens ONLY when the repaired faucet is being opened.
Chances are if you open the faucet a bit more or less the water hammer may stop but that's not a great solution.Instead search InspectApedia.com
for WATER HAMMER NOISE DIAGNOSE & CURE - home to see how to diagnose and cure the problem.
On 2016-07-09 by Tracy
I recently shocked my private dug well with bleach, flushed throughout the system by turning on all taps. Ended up with a large amount of sediment coming out of the taps which took about a day to clear but now I have low water pressure (water flow) at all fixtures.
We replaced the pressure control switch and the pressure gauge, checked the pressure tank at the schraeders valve to ensure it was 2 PSI below the cut off pressure (30/50) and everything checks out.We also checked the filter and cleaned it out so it's no longer clogged with sediment.
The pump is cutting in at the appropriate pressure, the pressure tank is holding pressure at 50.
We did end up installing a check valve at the water supply just before the pressure tank as we had an issue with short cycling it seemed the water was draining back down to the well and the pressure tank couldn't hold pressure.
We figured the check valve at the pump was clogged or damaged due to the increased sediment; the new check valve seems to have cured that.
But we are still left with low water flow at all fixtures (cleaned all aerators too). I'm hoping someone can help me figure this out. I feel like a putz because everything was fine until we shocked our well to get rid of a rotten egg/wet dog smell but it's come back and now we are left another problem.
Any help is much appreciated!
On 2016-07-10 by (mod) -
Tracy,
Large amounts of sediment would more likely be due to low water in the well or a damaged well casing than to having shocked the well.
Your check valve experience suggests that the foot valve in the well is not working - a source of loss of well pump prime.
Low water "pressure" at all fixtures is probably low flow, not low pressure, as your tank shows 50 psi which is pretty good. I suspect that there is debris clogging in the piping system somewhere.
The rotten egg smell sounds like a bacteria or sulphur problem in your system, perhaps in the water supply.
Search InspectApedia.com for SULPHUR ODOR IN WATER to read about that problem.
Search InspectApedia.com for LOSS OF WATER PRESSURE to read steps in diagnosing and fixing that problem.
A possible relation between shocking the well and the problems you cite now might be having run so much water to flush out the bleach that you exhausted the well.
On 2016-06-09 by Anonymous
Can intense heat from a fire cause a toilet to burst?
On 2016-06-09 by (mod) -
If you mean cracked porcelain, perhaps so. Or intense heat followed by soaking during extinguishment.
On 2016-05-04 by lfurlow@cox.net
Can cast iron drain pipes that are obstructed by rust to a 3/4 inch opening be cleared by reaming, drilling, etc. without re-piping?
On 2016-05-04 by (mod) -
Perhaps, but I've never had much success with those attempts. The problem is more likely with hard exfoliating corrosion build up in galvanized iron pipes.
If a cast iron or galvanized pipe us so corroded as to block itself, even if you could remove the blockage you'd have lost so much metal that the piping is not reliable. I'd replace the bad sections.
On 2016-04-22 by 57
First off, great website, a phenomenal resource and wealth of info! My issue has stumped a few plumbers already, so not sure if you had seen it before. Moved into 5y/o house last year and hot water pressure was terrible. Followed your guide for flushing HW tank, but no change.
Just recently noticed that when I turned off sprinkler system, few days later 'pop', hot water flowed great. Month later, when I resumed using sprinkler system, no hot water again.
Turned on all hw outlets in house, then 'pop' hot water again. Seems to me air is being introduced into the HW tank or line by the irrigation and causing an airlock. Have you seen anything like this before? City water, no filters or softeners or anything else. Thanks!
On 2016-04-22 by (mod) -
Thanks 57, we work hard to provide useful information and so are thrilled when you find it so.
What you describe, from my very remote and limited view, sounds as if a control or valve is sticking.
If you are seeing actual air discharge at the fixtures search InspectApedia for AIR DISCHARGE at FIXTURES to read causes and cures.
But I think air discharge and water pressure are independent / different problems. That is, for a bolus of air in water pipes or appliances to be able to block water flow it would have to
1. be at a pressure higher than the water source or well pump can produce
2. be in a closed system: that is, air would flow along the building pipes and come out at any faucets or fixtures that are opened to let water flow. That in turn would drop the air pressure to zero and permit the pump to push the air out and water in.On 2016-04-22 by 57
Thanks!! That's the curious part, there's no valves going in or out of HW heater, it's a straight cPVC connection. I feel no air or sputtering comes out of faucet when there's no hot water, just nothing there.
Is there any way that the irrigation system is pushing air in/out when it's turns on/off? Could there be a leak or something somewhere in the irrigation system that would increase the pressure enough to push air into the closed system? What else could this possibly be? It's stumped everybody so far! :) thanks!On 2016-04-22 by (mod) -
So 57, if I'm right that you have cold water and no hot water flow we know that the blockage is at some point between the cold feed into the water heater and the plumbing fixtures where hot is turned on.
If there is no hot water at any fixtures then we can figure the blockage is between the same starting point and the first point in the hot water supply piping where the supply from the water heater branches off to feed more than one fixture.
You say that the problem is intermittent and follows use of the irrigation system. That system is surely using only cold water.
You think it's air-lock but you never see air discharge from fixtures.
From these clues I suspect that air binding is not the problem (though I admit I'm arm-waving and speculating).
Rather I suspect something like this: when running the irrigation system the in-building water pressure drops significantly.You could, depending on how pipes and pumps are arranged to irrigate, even be creating a vacuum in house water piping - for example if an irrigation pump sucks water so fast that water is drawn from not only the well but also from the building supply piping system.
IF you had backflow preventers or checkvalves in the system those would prevent house water from ever flowing backwards out of the building.
But sudden or significant pressure drops in the house system MIGHT cause a checkvalve to stick, or might cause a bit of debris (say a chunk of plastic from a failed pvc dip tube in a water heater) to get sucked against the water heater outlet.
Either of those could partly or even fully block water output, and either might suddenly "correct itself" if the pressure into the house piping system then turned around and increased.
I don't have a clear understanding of your water system: is it all private well supply? Are there check valves and backflow preventers? Am I right that you've never seen air discharge anywhere when water flow returns or at other times?
It would be informative to install (or observe existing) pressure gauges on your system at a couple of key points, but particularly at the house side of your water pump and at the water heater (maybe a portable gauge on the heater tank drain valve).What are the gauges reading during the good and bad hot water flow conditions?
On 2016-02-10 by Anonymous
My upstairs shower has hot and cold temp swings when the downstairs kitchen sink is used. I replaced the defective MOEN valve in the shower, but the problem is still there. What more can I do?
On 2016-02-10 by (mod) -
You could install a tempeature control valve or tempering valve right at the shower.
On 2016-02-10 by Vicki
Kinda a strange question but....
I have an underground water well and it has recently broke, for the time being I bought two water tanks and hooked them into the house, my question is what is the name of the part that keeps the water from flowing backwards from my tanks down to the well seeing how all the pipes are connected to the well?
On 2016-02-10 by (mod) -
Vicki you refer to a check valve or a foot valve.
On 2015-12-04 by john
farm house upstairs shower hotwater but no cold other fawcets and 2nd shower ok. help!
On 2015-12-04 by (mod) -
Look for a clogged supply pipe elbow or valve or if you are in a freezing climate a frozen pipe.
On 2015-09-02 by Anonymous
what happened if we install pipes below the level of pumps and water tank
On 2015-09-02 by (mod) -
If your system has no check valves you may siphon water out of the system IF the pump is turned off. When the pump is turned on (which is normal - that is to say power is on to the pump) then whenever pressure drops below the pressure control's cut-in pressure the pump will work normally regardless of the piping routing.
On 2015-05-24 by cathy
when I cut my water on it will run for a little while,, then it stops running
then it will start back running what is the problem
On 2015-06-12 by (mod) -
Cathy
A most common cause is when your pump exceeds the well flow rate and is being shut off by a pump protection circuit; of course there could be other causes.
...
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