high pressure in the morning

[konaka]

hi forum,

when i wake up and turn on the faucet the water pressure is extra high for a few seconds. when the faucet runs for a few seconds the pressure goes back to normal.

if i leave all the sinks turned off for a few hours in the day the same thing happens. so, this doesnt have anything do to with the morning, just that the water has been off for several hours for the pressure to build up.

i think i need to replace the water pressure regulating valve. is that the right thing to do?

 

[johnjh2o]

Your on the right track. Repair or replace the PRV valve. Replacement in most cases is the way to go.

John

 

[Caduceus]

Sound like a thermal expansion issue from the tank heating. Do you have a thermal expansion tank on you plumbing system?

 

[Caduceus]

Let me add that by having excessively high pressure as well as thermal expansion, the pressure increase will be more dramatic. Both probably need to be addressed.

 

[konaka]

yes we have an expansion tank on our water heater

i guess i could check to see if it has the right pressure in it's bladder. not sure what the pressure should be but i might be able to look that up in the manual or something. perhaps it should be 50psi like water pressure in the house. ?

 

[Caduceus]

Yes, it should, if you got 50 psi already on the house pressure. You need to shut the water off to the house and open a faucet to relieve the house pressure before checking the expansion tank's pressure. A tire gauge that can read 50 psi or more is needed. If you depress the nozzle on the tank and you get water instead of air, the expansion tank needs to be replaced. Also be sure that the hot water tank temperature is set to normal range and not too high.