On Mon, 4 Feb 2013 19:38:59 +0000 (UTC), Cydrome Leader
wrote:

In rec.crafts.metalworking PrecisionmachinisT wrote:

"Existential Angst" wrote in message
...
wrote in message
...
A friend has a house that came with two identical water
heaters hooked up in parallel. He doesn't need all the capacity,
so we turned one of them off and turned off the water going
into it. This was several years ago. The water heater was
about 4 years old at the time, it's now 7 years old.

Given that a tank has already had some service, what would
you guys do to try to keep the spare tank available for as long
as possible?

Leave it full of water?

Drain it?

My thought was that draining it would be worse, because
allowing air in, it would rust.......



Fill it with water, add a rust inhibitor?

As an aside, shouldn't two water heaters be hooked up in series?
Been meaning to post that to the group. The rcm peeple should have some
insights into both Qs.


Having a second tank that's unpowered, uninsulated, and plumbed in series so
that cold water passes through it first will reduce summertime AC and water
heating costs by naturally warming the inlet water up to room temp.

Other than skinning a trashed water heater, most of which are leaking
anyways, are there purpose made tanks for this use? I've been looking for
something along these lines to get "room temp" water for a photographic
darkroom where there's extended draw of water.

Anything homemade looking and attached to the water lines before the
backflow preventers might draw attention from the landlord or inspectors.
Just adding a waterheater-ish tank before the existing one would be the
easiest, as long as it draw no attention and won't burst over the weekend.


You could get a water heater that's being replaced before it bursts.
Just add a valve on its inlet side so there is no pressure on it when
it's not in use. It should last a long time without constant pressure
on it. If it does leak, you're right there.