Water pressure spikes

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cjhaddenjr

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I'm trying to figure out what is causing spikes in my water pressure in my home. i have my PRV set to 45 psi, no expansion tank, no back flow preventer or check valve. Street pressure according to water company is around 90 psi. I've installed a pressure gauge with the red pointer on an outside faucet that shows pressure max and have seen it as high as 90 psi. Just cracking a faucet sends it back to 45 psi. Could my water heater still be the problem? Could my three year old PRV intermittently be leaking by? Should I even worry about this?
Thanks, Curtis
 
i have my PRV set to 45 psi, no expansion tank, no back flow preventer or check valve. Street pressure according to water company is around 90 psi. I've installed a pressure gauge with the red pointer on an outside faucet that shows pressure max and have seen it as high as 90 psi.

Your PRV must have a back-flow device or the pressure would not increase or the PRV is faulty or not adjusted correctly.

This leaves only THERMAL EXPANSION and 90# is very hard on the system.
 
Your PRV must have a back-flow device or the pressure would not increase or the PRV is faulty or not adjusted correctly.

This leaves only THERMAL EXPANSION and 90# is very hard on the system.
Like ^^^ he said. PRV
 
First...when water pressure exceeds 80 psi you need a pressure regulator and when you have a pressure regulator you need an expansion tank. Also all of your plumbing fixtures have a max pressure rating (water heaters, faucets, ect.).
If I see 60 + in my home I'm concerned and fixing that right away. You don't need more than 50 in a home. More pressure = more plumbing repairs.
 
After much debate I finally spent the money and installed an expansion tank and now I now longer have these spikes.
 
................................................
whaaaaaaa.......

now, look,,,,a prv is set at 45 psi in your house,
prv.s are not supposed to let the pressure get above what it is set for, it it does, it is a faulty pvr

you have not solved the underlying problem, all you have done, is fixed the symptoms

at 45 psi you do not need a expansion tank
 
................................................
whaaaaaaa.......

now, look,,,,a prv is set at 45 psi in your house,
prv.s are not supposed to let the pressure get above what it is set for, it it does, it is a faulty pvr

you have not solved the underlying problem, all you have done, is fixed the symptoms

at 45 psi you do not need a expansion tank

What is about Thermal Expansion that you do not understand ... :confused:

(Standby Mouseketeers... I feel a long knock-down slug-fest coming... :D )

Thermal Expansion _2.jpg

Thermal Expansion _3.jpg

Thermal Expansion _4.jpg

TET - Section 608.2.jpg
 
Water heater control failure or malfunctioning PRV's are not the reason for an expansion tank. As soon as water is heated it expands. ... If a water heater continues to heat, and a PRV is in place, the pressure can cause the heater to fail. The T&P valve is supposed to protect against this.
since the W/H was not off, and the pop off did not pop off, that is an indication that the problem is a bad prv

do you understand how to gather facts and give a correct diagnosis ?

if the pop off was poping off, that would tell you the water was expanding, with no where to go. but it did not
so, that tells me it is not expansion..

next fact

the system was creeping up to the SAME psi as city pressure outside HMMMMMMMMM..if it were expansion, this would not happen

all the symptoms for this point to a bad prv.


oh..i forgot. you like a lot of pictures and graphs

chinese-food.jpg

C2poWOsWIAIecoz.jpg

2016-07-11_0724  2009---2013 fbistats.jpg

oldfart.jpg
 
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OK...

The problem was that the drain for that particular valve exited to outside causing the drain-line to freeze and the valve becoming non-operational. Install was obviously not to code. Had he moved the drain inside the home the freezing would have subsided and the valve would have been fully operational to lessen thermal expansion volume.

If there is a anti-reverse flow device on the PRV (they can be had either way, correct?), the thermal expansion would have been released through the pressure reducing valve before the WH (depending on rating) and finally the TPRV @ the WH (if functional) would have been the system fail-safe only if another component hadn't failed in the system due to over-pressurization.

Now, as thermal pressure increased, it had nowhere to go but out the TPRV @ the WH if one was installed and operational.



The valve @ the WH had a frozen discharge line. Who knows if he ever looked at the TPRV @ the WH?




AGAIN-


what post are you reading ?

frozen pipes,,,,,discharge ??????WTH?????
 
I'm trying to figure out what is causing spikes in my water pressure in my home. i have my PRV set to 45 psi, no expansion tank, no back flow preventer or check valve. Street pressure according to water company is around 90 psi. I've installed a pressure gauge with the red pointer on an outside faucet that shows pressure max and have seen it as high as 90 psi. Just cracking a faucet sends it back to 45 psi. Could my water heater still be the problem? Could my three year old PRV intermittently be leaking by? Should I even worry about this?
Thanks, Curtis


................................................whaaaaaaa.......

now, look,,,,a prv is set at 45 psi in your house,
prv.s are not supposed to let the pressure get above what it is set for, it it does, it is a faulty pvr

you have not solved the underlying problem, all you have done, is fixed the symptoms

at 45 psi you do not need a expansion tank


Water heater control failure or malfunctioning PRV's are not the reason for an expansion tank. As soon as water is heated it expands. ... If a water heater continues to heat, and a PRV is in place, the pressure can cause the heater to fail. The T&P valve is supposed to protect against this.
since the W/H was not off, and the pop off did not pop off, that is an indication that the problem is a bad prv

do you understand how to gather facts and give a correct diagnosis ?

if the pop off was poping off, that would tell you the water was expanding, with no where to go. but it did not
so, that tells me it is not expansion..

next fact

the system was creeping up to the SAME psi as city pressure outside HMMMMMMMMM..if it were expansion, this would not happen

all the symptoms for this point to a bad prv.

oh..i forgot. you like a lot of pictures and graphs

OK... Now that Earth Control has re-established my orbit... :(

Yes, a PRV controls incoming water pressure from the municipal system. Depending on the PRV model/style, it may or may not allow excess house pressure to bypass it and return to the municipal system.

The OP stated that he has a PRV installed and adjusted to 45PSI max. but has tested water pressure to 90PSI at times with a test gauge. He did not say what the pressure was when the gauge was installed but over a time period just the max pressure @ 90PSI (actual supply pressure is not known).

So that would indicate to me... :D ... that a thermal expansion event is happening. The TPRV is calibrated (if functioning properly) to release pressure @ 125PSI. A TET is needed so as to absorb the excess pressure, not wait until the TPRV fully opens (not dribble) and release the excess pressure (at it's high setting damage in the system may all ready have occurred)

The TPRV is for emergency protection only, not to be allowed to dribble to hopefully control high pressure(s) in the system. It may lead to early valve failure.

Before replacing anything, the OP has to diagnose the problem from square one. Regardless, code now calls for a TET install when a non-back flow PRV is installed.
 
OK... Now that Earth Control has re-established my orbit... :(

Yes, a PRV controls incoming water pressure from the municipal system. Depending on the PRV model/style, it may or may not allow excess house pressure to bypass it and return to the municipal system.

The OP stated that he has a PRV installed and adjusted to 45PSI max. but has tested water pressure to 90PSI at times with a test gauge. He did not say what the pressure was when the gauge was installed but over a time period just the max pressure @ 90PSI
he did say what the pressure was gauge was installed, it was 45 psi,
then, he noticed pressure creep to 90 psi,,,intermitenly

(actual supply pressure is not known).According to the city, water pressure is 90 psi
with a need for expansion tank, the pressure would not stop at 90
it would rise

T&P valves are 150 psi not 125
So that would indicate to me... :D ... that a thermal expansion event is happening. The TPRV is calibrated (if functioning properly) to release pressure @ 125PSI. A TET is needed so as to absorb the excess pressure, not wait until the TPRV fully opens (not dribble) and release the excess pressure (at it's high setting damage in the system may all ready have occurred)

The TPRV is for emergency protection only, not to be allowed to dribble to hopefully control high pressure(s) in the system. It may lead to early valve failure.incorrect, they do dribble, that is the first indication you have a problem

Before replacing anything, the OP has to diagnose the problem from square one. Regardless, code now calls for a TET install when a non-back flow PRV is installed.

I'm trying to figure out what is causing spikes in my water pressure in my home. i have my PRV set to 45 psi, no expansion tank, no back flow preventer or check valve.

Street pressure according to water company is around 90 psi.

I've installed a pressure gauge with the red pointer on an outside faucet that shows pressure max and have seen it as high as 90 psi. Just cracking a faucet sends it back to 45 psi. Could my water heater still be the problem? Could my three year old PRV intermittently be leaking by? Should I even worry about this?
Thanks, Curtis
Temperature and Pressure (T&P) relief valves

Temperature and pressure (T&P) relief valves used on residential water heaters are typically designed and manufactured to relieve on pressure at 150 psig and on temperature at 210 degrees F. These ASME, ANSI and CSA (AGA) approved relief valves protect the water heater from excess pressures and temperatures by discharging water.

In normal operation of the water heater and T&P valve, no water should be discharged from the valve. A T&P valve that discharges is an indication of an abnormal condition in the system and by discharging, the T&P valve is meeting its designed safety purpose. The causes of discharge can be thermal expansion, excess system pressure, low temperature relief, too high a setting on the water heater, or something in the water heater causing excess temperatures in the heater.

Thermal Expansion: When water is heated it expands. In a 40 gallon water heater, water being heated to its thermostat setting will end up expanding by approximately 1/2 gallon. The extra volume created by this expansion has to go somewhere or pressure will dramatically increase, such as when water is heated in a closed system.

A good indication of thermal expansion is when the T&P valve releases about one cup of water for each 10 gallons of heater capacity with each heating cycle. The T&P valve is functioning properly when it relieves pressure caused by thermal expansion, but frequent relief can build up natural mineral deposits on the valve seat, rendering the valve inoperative. This condition can be addressed by the installation of a Watts thermal expansion tank or other Watts thermal expansion device to protect your system from overpressure caused by thermal expansion. If there is no discharge from the valve, there is no need to replace the valve.

System Pressure: If installation of a thermal expansion device does not relieve occasional dripping from the T&P valve, then the system pressure should be checked. If system pressure is excessive (typically more than 75 PSI), a Watts pressure regulator should be installed on the incoming water line.

Warning: The discharge from a T&P valve can be very hot. It is very important that all T&P valves be installed properly with a discharge line piped downward to an adequate drain to avoid property damage and to minimize possible human contact. Please read and follow the instructions on the warning tag attached to your T&P valve.


question, why, in your opinion, would a system that has been working
with out any problems, all of a sudden require a expansion tank ?
would it not be a logical conclusion, that a part of the system has failed ?
would it not be in the best interest of the client to find the part that has failed.?

I agree, the op needs to inspect the system to find the CAUSE
not mask the symptom by installing an expansion, and calling everything good. the original problem still exists,

time for school.
how would he diagnoses that it is the prv causing creep and not expansion ?
 
question, why, in your opinion, would a system that has been working
with out any problems, all of a sudden require a expansion tank?

It is not known for certain that the system was functioning properly.

would it not be a logical conclusion, that a part of the system has failed ?
would it not be in the best interest of the client to find the part that has failed.?

Yes, a part of the system has failed, the absence of a TET.

I agree, the op needs to inspect the system to find the CAUSE
not mask the symptom by installing an expansion, and calling everything good. the original problem still exists,

Exactly. His first step would to be to determine supply pressure (gauge @ sill cock) before the PRV, not what the city says is normal pressure as it may vary @ different locations and can vary by time periods.

time for school.

how would he diagnoses that it is the prv causing creep and not expansion ?

:(

ORIGINAL COMPLAINT-

I'm trying to figure out what is causing spikes in my water pressure in my home.

* i have my PRV set to 45 psi,

* no expansion tank,

* no back flow preventer or check valve.

* Street pressure according to water company is around 90 psi.

* I've installed a pressure gauge with the red pointer on an outside faucet that shows pressure max and have seen it as high as 90 psi. Just cracking a faucet sends it back to 45 psi.

NOTE- Was supply line to sill-cock installed before or after the PRV?

Could my water heater still be the problem? Could my three year old PRV intermittently be leaking by? Should I even worry about this?

Thanks, Curtis

My diagnosis... :cool:

1) Put test gauge on sill cock and leave for 24hrs. Record @ install and record highest pressure read.

2) Move gauge to house side of PRV and record pressure @ install and leave for 24hrs. The WH should be OFF (power supply) during this test.

3) If pressure remains at whatever the PRV is set at, it is not the PRV. If the pressure varies, it is most likely the PRV.

4) Leave the gauge on (reset) and allow to read system pressure for 24 hrs. Turn on WH power. If there is a rise in pressure at anytime, you need some sort or Thermal Expansion Control Device.

5) If Thermal Expansion is found to be the culprit, leave gauge on another 24hrs after install to make sure.

Again, the TPRV is an emergency feature only (why you have to manually test it on a schedule). If there is any malfunction in the system that trips it, it may get out of calibration or have it's pintle jammed by sediments.

And the TET install is also a safety device.

I am off my high horse now as I confused one or more same complaint threads with this one.

TPRV (Relieve Pressure @ 150 PSI - Temp @ at 210 Degrees F)

TPRV _1 (Relieve Pressure @ 150 PSI - Temp @ at 210 Degrees F).jpg
 
It is not known for certain that the system was functioning properly.



Yes, a part of the system has failed, the absence of a TET.



Exactly. His first step would to be to determine supply pressure (gauge @ sill cock) before the PRV, not what the city says is normal pressure as it may vary @ different locations and can vary by time periods.



:(

ORIGINAL COMPLAINT-



NOTE- Was supply line to sill-cock installed before or after the PRV?



My diagnosis... :cool:

1) Put test gauge on sill cock and leave for 24hrs. Record @ install and record highest pressure read.

2) Move gauge to house side of PRV and record pressure @ install and leave for 24hrs. The WH should be OFF (power supply) during this test.

3) If pressure remains at whatever the PRV is set at, it is not the PRV. If the pressure varies, it is most likely the PRV.

4) Leave the gauge on (reset) and allow to read system pressure for 24 hrs. Turn on WH power. If there is a rise in pressure at anytime, you need some sort or Thermal Expansion Control Device.

5) If Thermal Expansion is found to be the culprit, leave gauge on another 24hrs after install to make sure.

Again, the TPRV is an emergency feature only (why you have to manually test it on a schedule). If there is any malfunction in the system that trips it, it may get out of calibration or have it's pintle jammed by sediments.

And the TET install is also a safety device.

I am off my high horse now as I confused one or more same complaint threads with this one.

TPRV (Relieve Pressure @ 150 PSI - Temp @ at 210 Degrees F)


you are brain fuking every problem instead of thinking you are relying
on goggle search to give you answers

why in the hell would i want to spend 24 hours or more at a clients house?

valve off the expanson tank and water heater, put a gauge on cold side washing machine boiler drain
if it creeps it is prv, if it does not it is expansion

the first clue is lack of water at the T&P
2nd clue, is it just started,
sometimes you listen to what people do not say, to find out what they mean

mic-drop.jpg
 
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you are brain fuking every problem instead of thinking you are relying
on goggle search to give you answers

I get answers here frodo, many different answers and opinions and I GOOGLE to understand the theory.

why in the hell would i want to spend 24 hours or more at a clients house?

Damn if I know. You questioned me about how I would go about it. I understand that you do not have that luxury.

valve off the expanson tank and water heater, put a gauge on cold side washing machine boiler drain
if it creeps it is prv, if it does not it is expansion

There is no expansion tank in his description. You mean on a service call where there are both?

the first clue is lack of water at the T&P

He never said anything about his TPRV. And 90# should not trip it (unless it is defective). The pressure will be contained within the system.

2nd clue, is it just started,
sometimes you listen to what people do not say, to find out what they mean

How is it known it just started?

HAVE A NICE DAY! :D
 
water commission has been known to pop relief valves in hot water tanks when servicing main lines. Expansion tanks are put in place to act as shock absorbers.
 

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