Weirdest water pressure problem

[MaxxAIM]

Ok so this is really starting to bug me cause I can't figure it out.

Here is how the original flow of water went.

90 psi in -> water meter --> water heater and valve ends


everything worked fine no issues here

so I decided to install a whole house water filter rated for 100psi re-did the piping so it sits right after the water meter, no leaks no issues

at some point during the night the water heater PRV starts letting some water out, after checking the PRV for defects i left it alone, i put the water filter on bypass and no PRV issues for 4 days after that, turned the water filter on, in 2 days, again some leaking from water heater PRV

my initial guess was the 90psi coming into the house, I got a pressure reducer (watts not the cheap one) rated for 400psi range from 25 to 75 and set the psi to 70. At this point i hooked up a brand new washer and dryer where the valve ends were. I just assumed things would work right and didnt mind adding them to the equation.

so now we have
90 psi in -> water meter -> reducer (70psi) -> my psi gauge -> water heater and washing machine


now the water heater randomly makes some clanking noise, not all the time, just pretty random i think, and 3 days later again, PRV leaks and now the water filter is showing bad filter. i checked my own gauge when the noises on water heater were clanking it showed 90psi as if it just bypassed the reducer, i flushed the toilet, pressure dropped to 70psi, no noise.

WTF ? heh someone please help I'm lost.

I made a bypass line for all of the piping so it flows like in its original state, when its in original state, no PRV leaks, no nothing, if its bypassing the filter no issues.

I feel like it has to be some issue with water spiking from outside, or maybe thermal expansion from the water heater, but if its thermal expansion why does it not cause any issues when filter is bypassed ?

So confused !!! Please someone help!

 

[johnjh2o]

Your confusing a PRV with a T&P relief valve. A PRV is the pressure reducing valve you installed. It's purpose is to reduce the pressure in the home. The T&P relief valve is a safety valve that is installed on the water heater to relive access pressure on the heater. Your on the right by installing the PRV valve. But you also have to install a thermal expansion tank on the heater. A PRV also acts like a check valve. When the heater starts heating the water it expands and if it has no were to go it increases the pressure to the point of opening the T&P relief valve. Before the PRV valve was installed the access would dissipate into the City water mains. A thermal expansion tank will prevent the pressure from increasing.
http://www.watts.com/pages/learnAbout/thermalExpansion.asp?catId=64

John

 

[MaxxAIM]

PRV = pressure release valve, its the P in the T&P, we're talking about the same thing

I didn't think the thermal expansion would push it all the way back to the main meter, but I guess it goes that far. The expansion tank goes on the hot out line or pre water heater ?

 

[KULTULZ]

The expansion tank goes on the hot out line or pre water heater ?

Contained within the posted tech article (WATTS)-

(Shown with tempering valve installed. Ignore or research tempering valve.)

 

[speedbump]

Note; that in the above illustration, there is no "Whole House Filter" because they are useless.

 

[zkirtlink]

thermal expansion is normally absorbed back into the water source back through the meter the expansion is the same as a car tire pressure rises when hot from driving for a while. the water expands in the pipe and needs to go some where or your pressure will spike causing the t&p to release the pressure slowly. when you installed the filter it must have a type of checkvalve built into it unless you installed one. the expansion tank will fix your issue. they are installed regularly where new homes are installed with backflow preventers after each meter.

 

[johnjh2o]

thermal expansion is normally absorbed back into the water source back through the meter the expansion is the same as a car tire pressure rises when hot from driving for a while. the water expands in the pipe and needs to go some where or your pressure will spike causing the t&p to release the pressure slowly. when you installed the filter it must have a type of checkvalve built into it unless you installed one. the expansion tank will fix your issue. they are installed regularly where new homes are installed with backflow preventers after each meter.

A PRV will have the same effect as a check valve or back flow device.

John