Does a water heater need a pre and a post shutoff valve?

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Does a water heater need a pre and a post shutoff valve?

Author: o2458NUEjHxmj9dcgkKA (TN)

There is a shutoff valve at the cold water input to my water heater immediately before the flexible wire braid input. There is also another shutoff valve immediately after the wire braid output from the water heater. Either one of them shuts off all the hot water in the house.

The post-water heater shutoff valve is leaking. I would like to replace the leaking valve with a straight piece instead of a new shutoff. It seems redundant to have two valves that do the same thing.

Can anyone tell me why there are two shutoffs?

What does the forum think?

Re: Does a water heater need a pre and a post shutoff valve?
Author: srloren (CA) It helps when changing out the WH. The water in the hot lines do not drain out causing a mess or water that needs to be captured into a bucket. If you live in a 1 story home just use the one on the cold side. srloren
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Re: Does a water heater need a pre and a post shutoff valve?
Author: packy (MA) yeah, the only time a post shutoff is needed is when replacing the heater. even then it is a matter of convenience rather than necessity.
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Re: Does a water heater need a pre and a post shutoff valve?
Author: DaveMill (CA) In our rental cabin, there is a cutoff on the hot water side (output) of the heater. But not on the input side. Go figure.
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