Our cold water faucets always produce an initial stream of hot water before
the cold starts. I believe it has to do with the expansion tank on the
heater. There is a check valve on the water line that feeds the heater, but
the backflow seems to indicate that it does not work. It is the flapper
type and it is pointed down. Is there a problem with trying to use this
sort of check valve in a downward position? I checked the arrow marking and
it appears to be installed in the right direction.

On Jul 5, 8:50�am, "Dan Listermann" wrote:
Our cold water faucets always produce an initial stream of hot water before
the cold starts. �I believe it has to do with the expansion tank on the
heater. �There is a check valve on the water line that feeds the heater, but
the backflow seems to indicate that it does not work. �It is the flapper
type and it is pointed down. �Is there a problem with trying to use this
sort of check valve in a downward position? �I checked the arrow marking and
it appears to be installed in the right direction.

might be the cold water line is close to something that produces heat
like the water heaters flue? anything that produces heat... even the
cold water line close to the hot line.

might be a good idea to go inspect the entire line runs.....

Plumbing can be simple, yet complex.

Yes that type of check valve should be installed horizontal with the hinge
portion of the valve up. Then gravity wants to hold the valve in the closed
position. Wrong way water flow will instantly be blocked. Right way water
flow will have enough pressure to open the flapper.

With that said, water when heated EXPANDS! So be darn sure there is a
properly functioning expansion tank directly connected to the water heater
with no check valves in-between AND a T&P valve (Temperature and Pressure
safety valve) installed on the water heater.

Then as water heats and expands, it has somewhere to go (expansion tank).
And should the expansion tank malfunction or the water heater malfunction
and heat the water too much, the T&P valve will release excess pressure and
prevent an explosion.




"Dan Listermann" wrote in message
Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion tank on
the heater. There is a check valve on the water line that feeds the
heater, but the backflow seems to indicate that it does not work. It is
the flapper type and it is pointed down. Is there a problem with trying
to use this sort of check valve in a downward position? I checked the
arrow marking and it appears to be installed in the right direction.

Dan Listermann wrote:
Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion
tank on the heater. There is a check valve on the water line that
feeds the heater, but the backflow seems to indicate that it does not
work. It is the flapper type and it is pointed down. Is there a
problem with trying to use this sort of check valve in a downward
position? I checked the arrow marking and it appears to be installed
in the right direction.

That kind of check valve needs gravity to be naturally closing the flapper to
work properly at low flows. The flapper should be hanging down from it's hinge
point if the valve is horizontal, or the flapper should be at the top if
vertical, so it is always closed at no flow. The simplest solution for you might
be to replace it with a spring check valve that doesn't depend on gravity.

Dan Listermann wrote:
Our cold water faucets always produce an initial stream of hot water before
the cold starts. I believe it has to do with the expansion tank on the
heater. There is a check valve on the water line that feeds the heater, but
the backflow seems to indicate that it does not work. It is the flapper
type and it is pointed down. Is there a problem with trying to use this
sort of check valve in a downward position? I checked the arrow marking and
it appears to be installed in the right direction.



If the "initial stream" starts immediately when the faucets haven't been
opened for an hour or so, then it probably isn't backflow, unless there
isn't much distance between the heater and the faucets.

If it takes several seconds before hot water appears after opening a
cold faucet then your presumption about the check valve may be correct.

Can you try telling what's going on by feeling the cold water piping on
both sides of the check valve while someone else opens a cold faucet?

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10e12 furlongs per fortnight.

Dan Listermann wrote:
Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion
tank on the heater. There is a check valve on the water line that
feeds the heater, but the backflow seems to indicate that it does not
work. It is the flapper type and it is pointed down. Is there a
problem with trying to use this sort of check valve in a downward
position? I checked the arrow marking and it appears to be installed
in the right direction.

Heh! My water pipes go through the attic.

Yesterday, the attic's temperature reached 134°F (even though it was a balmy
104° outside).

"Dan Listermann" wrote in message
...
Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion tank on
the heater. There is a check valve on the water line that feeds the
heater, but the backflow seems to indicate that it does not work. It is
the flapper type and it is pointed down. Is there a problem with trying
to use this sort of check valve in a downward position? I checked the
arrow marking and it appears to be installed in the right direction.

In addition to the advice others have given, it may help to know that
crossflow leakage when a single handle faucet is turned off is possible and
can cause your symptoms.

Don Young

Dan Listermann | 2009-07-05 | 7:50:09 AM wrote:

Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion
tank on the heater. There is a check valve on the water line that
feeds the heater, but the backflow seems to indicate that it does not
work. It is the flapper type and it is pointed down. Is there a
problem with trying to use this sort of check valve in a downward
position? I checked the arrow marking and it appears to be installed
in the right direction.

The initial slug of hot water is probably the water that's in the pipe
in the wall. If it's an outside wall or the pipes run through the
attic, that water can get pretty warm.

After the water in the wall runs through, it's followed by water that
has been underground, or in the basement ceiling, or whatever depending
on how your house is built. Eventually, you get to water that has
_definitely_ been sitting underground.

--
Steve Bell
New Life Home Improvement
Arlington, TX USA

On Sun, 5 Jul 2009 11:47:15 -0500, "HeyBub"
wrote:

Dan Listermann wrote:
Our cold water faucets always produce an initial stream of hot water
before the cold starts. I believe it has to do with the expansion
tank on the heater. There is a check valve on the water line that
feeds the heater, but the backflow seems to indicate that it does not
work. It is the flapper type and it is pointed down. Is there a
problem with trying to use this sort of check valve in a downward
position? I checked the arrow marking and it appears to be installed
in the right direction.

Heh! My water pipes go through the attic.

Yesterday, the attic's temperature reached 134°F (even though it was a balmy
104° outside).

The water pipes in the house I lived in in Livingstone Zambia had the
pipes on the outside, and the water mains were about 6" underground.
Never turned the geyser on in the hot season, and the water from the
COLD tap was hot enough to steam sometimes.
British Colonial style system with float controlled gravity tank (like
a stock watering trough) in the attic, gravity flow to the geyser and
taps, so limited water pressure as well.

"jeff_wisnia" wrote in message
...

Can you try telling what's going on by feeling the cold water piping on
both sides of the check valve while someone else opens a cold faucet?

I did that and it gets hot right away. Are spring loaded check valves
common in house plumbing?

Dan Listermann wrote:
"jeff_wisnia" wrote in message
...

Can you try telling what's going on by feeling the cold water piping
on both sides of the check valve while someone else opens a cold
faucet?
I did that and it gets hot right away. Are spring loaded check valves
common in house plumbing?

They are commonly available at stores, if that's any help. Some may not be
suitable for hot water pipes.

Dan Listermann wrote:
"jeff_wisnia" wrote in message
...

Can you try telling what's going on by feeling the cold water piping on
both sides of the check valve while someone else opens a cold faucet?


I did that and it gets hot right away. Are spring loaded check valves
common in house plumbing?



I'd say that "Warm Hand Luke" test pretty much proves that your original
suspicions about the check valve not closing are correct.

The present valve may have worked when new, but might have gotten
grotted up over time and won't close now, which could have nothing to do
with its orientation.

I've always had good luck with Watts products.

Here's a data sheet on one of their series of spring loaded check valves:

http://www.watts.com/pdf/ES-600.pdf

One the right size should work slicker than snot to solve your problem.

After putting in a new check valve it wouldn't hurt to check the
expansion tank to make sure it's still working as it should. With the
present check valve "leaking" you wouldn't have noticed if the expansion
tank got "full" or has a ruptured diaphragm.

Happy Landings,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10e12 furlongs per fortnight.