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Default Water heater noise

On Mon, 6 Jul 2009 21:10:38 -0500, "TNSTAAFL"

Regarding the suggestion about draining \ flushing the tank to remove
sediment - my poorly designed house has the hot water tank far from any
exterior walls and without a drain to the outside - there is a pressure
relief valve that vents to the outside.

Would simply attaching a regular garden hose to the spigot at the bottom of
the tank and running the hose to the outside for the flushing process be OK?

To the extent the outside is lower than the inside, yes.

I assume that I'd need to turn the heating element OFF but leave the inlet

Absolutely. if the heating element isn't in water, it will burn out,
pretty quickly I think.

water ON when I flush the tank and just let it run for a while - correct?

Now it occurs to me that if the water is under pressure and flushing
the tank quickly, instead of just draining the tank with the water
intake off but 2 hot water faucets open elsewhere, like I've done a
couple times, which goes slowly, there could be enough turbulence to
stir up the sediment on the bottom. I don't know if that's good or
bad. It gets rid of the sediment but means if the drain can be
clogged, it takes less sediment, sediment less deep, to clog it.

Any potential problems with running the hot water out through the garden

You paid to heat that water, plus all that carbon thing. You might
want to turn off the power for a day or two before you do this.
You'll still have hot water for a while and rather hot water for a
while after that. I live alone and I think I went 3 days before I
ran out of hot water. You have to leave the cold inlet open or no
water will come out, so it gradually gets diluted. Cooling without
diluting, just because there is no electricity anymore, takes even

But read my other posts about flushing and possible valve clogging.
This has never happeend to me but also I've never flushed. Other
people here say it can happen. Apparently you only heard this noise
because you happened to be in the basement when someone used hot
water. Is that enough to do all this for?

Also, my hot water tank is right next to the AC blower unit - there's a
condensate line for the AC that runs to the outside - I was wondering about
having a plumber run a drain line from the pan that's under the hot water

You have a pan under the water heater but it doesn't drain anywhere? I
think I've heard of that. I may have even seen it. Maybe they
always put in the pan and leave it for someone else to run a pipe from
it to a drain, but you shoudl know that without a drain, it will
overflow soon after the water heater starts to leak. Almost right away
if the drain hole in the pan isn't connected to anything. At that
point, there IS no point to having a pan. The water heater will
usually leak slowly, but continuously, once it starts.

A metal pan or a plastic pan?

to tie into the condensate line for the AC drain - how much capacity
(what diameter pipe) would the condensate line need to accommodate an
emergency drain line for the hot water heater?

My friend had a condensate line that I think was 1/4 inch i.D. plastic
tubing, or at most 1/2 inch inside diameter. What do you have?

The draln hole on the pan is for 2" inside diameter, isn't it? And
it's the squares that matter. Pi r squared. So 1/2 inch diameter is
1/4 inch radius which is 1/16 times pi (3.14) square inches, which is
0.2 square inches. OTOH, two inches diameter is one inch radius
squared is 1 times pi is 3.14 square inches. 15 times as much**.
Plus there is the capacity of the pump to consider. I have no idea
what that is. As I said, leaks usually start small, maybe they never
start big and they never get bigger, I don't know. Find out.

**Actualy didn't have to do all that. The diameter is 2 inches is
which is *four* times 1/2 inch, so the area will be four x four times
as big. 16.

I "flooded" my basement when my first water heater. That is, an
eigtth of an inch but it got soaked up by all the cardboard boxes and
ruined them and that might have been the time it got to the next room
and loosened the vinyl or asphalt tile. If it got farther it would
have runined other cardboard boxes that things are stored in and the
rug would have gotten soaked.

That was a time when something else had already leaked and I thought
it was drying slowly, when in fact I eventually learned my basement
floor usually dries out in less than a day, but this time the leaking
water heater was keeping it wet for 4 days before I got suspicious.


"Oren" wrote in message
.. .
On Mon, 06 Jul 2009 15:14:17 -0400, LouB wrote:

I happen to be standing near the electric hot water heater while the
dishwasher was running. Hear noise like "rattling". Something to worry
about or just normal? Ideas please?


Occasionally I hear a "chatter" about the water heater. It resembles a
metal to metal sound. I figured the sound was coming from the flue
pipe/heater. Sometimes maybe wind in the exhaust pipe vent?

Not enough to worry about.