" wrote:



Q2) Would you think they are right?

I don't understand why you would do anything. The pressure
at my house is 80 psi, check it every once it awhile when it
seems the pressure is down. No expansion tank. Why do you
need one? The pressure relief valve on the hot water tank
takes care of protecting the hot water tank

The blow-off valve on the hot water tank is a safety feature.
It's not designed, and shouldn't be relied on, for frequent activation.
Expansion tanks are cheap insurance. Get one.

What makes you think there will be frequent activations? As
far as I know, the one on my new tank hasn't activated in 4
years. The previous one leaked after a few years and I
replaced it and then AFAIK it was never activated. Of
course it is designed to be relied on. Why would you
install a safety device that can't be relied on?