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Pellhurst Plumbing Co.

Planned work

The tank is
the easy part.

Anyone can put a new cylinder where the old one was. What decides whether it was done properly is everything connected to it — and none of that is visible once the job is finished.

Knowing when

It gives notice. Quietly.

A tank rarely fails without warning. It fails without warning that anybody was watching for, which is a different thing.

A tank water heater in a utility room with copper supply lines rising to the ceiling, a relief line running down the side of the tank, and a drain pan beneath it.
Supply and return rising, relief line running full-size down the side and terminating low, pan beneath. The parts that decide the job.
The one to act on: water on the floor around the base, or a relief line that has started to drip. The first means the tank is already through. The second means something is over pressure or over temperature, and that one is not a wait-and-see.

What to look for

Six things worth a look
next time you are down there.

Rust at the base, or on the fittings

A bloom of rust where the shell meets the floor usually means it has been weeping for a while. Rust on the connections alone is a different, smaller problem.

Recovery that has quietly doubled

Sediment insulates the bottom of the tank from its own burner or element. Nothing looks wrong; the hot water just runs out sooner than it used to, and nobody can say when that started.

A relief line that drips

The temperature and pressure valve is doing its job. The question is what made it open, and that answer is upstream of the valve.

Rumbling when it heats

Water boiling underneath a sediment layer. Not dangerous on its own, and a reliable sign the tank is working much harder than it is being paid to.

Its age, on the label

The serial number carries the build date. A tank well into its second decade is not a fault; it is a countdown you can now schedule around.

No pan, or a pan going nowhere

A drain pan with no drain catches about two gallons and then does exactly nothing. Worth knowing before the day you need it rather than after.

The day itself

What actually happens,
in the order it happens.

No part of this is dramatic. It is worth writing down anyway, because knowing the shape of the day is most of what makes it stop being stressful.

Isolate and drain

Water off at the tank, power or gas off at the source, and the old tank drained down. A full tank is heavier than the two people carrying it, which is the whole reason this step is first.

Out, and you see it

The old unit comes out and stays where you can look at it. If it failed, we show you where.

The pan and the floor

A pan that drains somewhere real, not somewhere convenient. This is usually the point at which an older install turns out to have had neither.

Set, connect, and the unions

The new tank set and connected with dielectric unions where copper meets steel, so the joint is not quietly corroding from the day it is made.

Relief line and expansion

The relief line run full-size, downhill, terminating low, with nothing in it that can be closed. An expansion tank where the system is closed, which is most of them now.

Fill, purge, fire, and watch it

Filled and purged before it is ever energized, then brought up to temperature and watched. The last part is the part that gets skipped, and it is where a bad joint announces itself.

What you are left with: the old tank on the drive, the new one running, the pan draining somewhere, and the label photographed so that in twelve years somebody can read the date without a flashlight.

The one real choice

Tank, or tankless.

There is no universal answer, and anyone who gives you one without looking at your gas line, your venting and how your household actually uses hot water is selling rather than advising.

A tank, again

The straightforward answer, and more often than not the right one. It goes where the old one went, connects to what is already there, and finishes the same day.

  • Nothing upstream has to change — gas line, venting and electrical stay as they are.
  • Simple to diagnose later, by us or by anyone else.
  • Delivers a fixed amount of hot water, then needs time. You already know how that behaves in your house.

Tankless

A genuinely better fit for some houses and a poor one for others, and which it is gets decided by the building rather than by preference.

  • Hot water that does not run out, at a flow rate the unit is sized for — not an unlimited one.
  • Usually needs a larger gas supply and its own venting. That is the part that decides whether it makes sense.
  • Wants descaling on a schedule in hard water. Skipped, it shortens the life of the thing you paid more for.
We will tell you which one your house is asking for, including when that answer is the cheaper one. The gas line and the vent run are checked before anything is recommended, not after something is ordered.

Doing it on a day you chose
is a different job.

If yours is into its second decade, it is worth a look before it makes the decision for you. If it is already leaking, that is a phone call rather than a page.