Where to cut? - Name this part!

[PA16v]

Hello knowledgeable people.

I am replacing my 60-gallon electric water heater, and I have this unknown elbow part on the cold water intake piping. It is most likely 15 years old, like my water heater.

What it is?

Do I cut on the A line and replace it with a new one?

Do I cut on the A line and not replace it?

Do I cut on the B line and keep it?


Thanks for your advice.

 

[Geofd]

are you pointing to "a" to the left of the valve is a tee on the run
is a female thread and whats threaded into it is a vaccum
breaker that fitting(vaccum breaker) is important and should
be changed with each new heater the cold water looks like its being
fed into the bottom of the tank?????cant see,what ever change
In pipi g you do that vaccum breaker must be there

Ohio..... That's weird we never install expansion tanks in residential
always in commercial/vaccum breaker still a must there to

Yes to your question

 

[PA16v]

Indeed, old one was bottom fed. New one is top fed.

So would my install diagram work with a vacuum breaker and an expansion tank?

 

[TomFOhio]

I never put vacuum breakers in a water heater for residential but the expansion tank is a must now a days. The only time we put vacuum breakers in was on commercial tanks as this is code around here. But on your drawing that will work just fine the way you have it.