New (Larger) Expansion Tank Causing Reduced COLD Water Pressure?

[busthead]

Hello,


Replacing a 2.1 gallon thermal expansion tank with a 5 gallon unit appears to have caused the cold water pressure to decrease. The toilet tanks fill more slowly. The water from the fridge dispenses more slowly.


I confirmed the pressure at a hose bib and increased the expansion tank precharge to 60 PSI.


I'm a DIYer, not a pro but I'm also not crazy. Something has changed. I just don't know how or why.


Please help!

 

[havasu]

Have you checked for sediment causing your cold water line to be partially blocked? I can't understand the loss of pressure except sediment.

 

[FishScreener]

Why did you take the precharge to 60-psi? It should be 2-psi lower than the minimum pressure.

I will assume that you shut the water off to install the new expansion tank.

Is it all the way open? Is it a gate valve which rarely gets operated? The gate can get stuck part way back open, if they are very old. When you exercise an old gate valve, it can then fail in any position.

 

[busthead]

Have you checked for sediment causing your cold water line to be partially blocked?

I have not but our house is only 13 years old. How should I check for sediment?

 

[busthead]

Why did you take the precharge to 60-psi? It should be 2-psi lower than the minimum pressure.

My understanding is that the expansion tank should be charged to equal the service water pressure - as measured at the hose bib.

The "minimum pressure" of what?

I will assume that you shut the water off to install the new expansion tank.

I didn't turn off the water to the entire house. Only the inline gate valve feeding the hot water heater. All valves are all the way open.