"RZ" wrote:

Also, if my problem can only be solved with pressure-equalizing fixture
sets, are there pressure-equalizing fixtures that have two taps (hot and
cold) so that I don't have rip out tile and drywall to create one center
hole.

Yes, one hole is used for temp control, one for volume flow.

According to RZ :
Now that I have your attention.....when ever the shower/tub is being used,
and either a cold or hot water tap is opened elsewhere in the house, the
unlucky person in the shower/tub gets cool water only...there is some
mixture of hot and cold, but the water temp drops significantly....

The copper piping from the hot water tank feeding both washrooms is
5/8 inch (outside diameter) throughout. Now, before I go out and purchase a
couple of pressure-equalizing fixture sets and have them installed, could
increasing the hot water feeder pipes to 7/8 inch solve my problem? I would
go with cheaper, easier to install poly pipe.

[I assume you mean switching 1/2 to 3/4 inch pipe ;-)]

It will _help_, but whether it will completely solve the problem depends
on a very large number of factors - pipe layout, feed flow restriction,
etc. In one home, I replaced some 1/2" runs with 3/4" and it made
a huge difference - so a simultaneous shower and something else was
okay.

This only worked the house was originally very strangely plumbed (the main
line made a complete circle of the "utility room" and went up and down
in size several times - probably due to a later water softener
installation), and the distribution layout was particularly conducive
to upsizing "subfeeders" before they split off to individual fixtures -
all in the utility room.

In other words, you have to drastically reduce all flow restrictions up to
the last "split" before the fixtures.

The improvement was idiosyncratic to that particular house. I wouldn't
expect to get anywhere near as much improvement in most homes. If your
flow problems are due to a restricted size municipal feed, you're
SOL.

You may be able to improve things quite cheaply with a low-flow
shower head, but still, it may not improve the situation much.

Nothing beats a pressure balance fixture. Which is what we're
using in our current house. In our current house, you can have
a shower without noticable temperature or flow changes while the
dishwasher, clothes washer, irrigation system and a water hose are
all running. On a well no less...

Also, if my problem can only be solved with pressure-equalizing fixture
sets, are there pressure-equalizing fixtures that have two taps (hot and
cold) so that I don't have rip out tile and drywall to create one center
hole.

It's usually not necessary to worry about that. Most p-bal fixtures have
optional bezels that will "convert" a two (or 3) holer to a "one holer".
When installed carefully, they work well.

[I installed a Moen p-bal valve in place of a three valve in a fiberglass
shower surround (I had access from the back). If I recall correctly,
I didn't have to cut the fiberglass at all, just silicone-seal the
bezel carefully to the fiberglass. Still working fine about 10 years
later...]
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

RZ wrote:
Now that I have your attention.....when ever the shower/tub is being
used, and either a cold or hot water tap is opened elsewhere in the

/snip/

Please set your system clock - it is at least 24 hours fast.

wrote in message
...
On Tue, 30 Nov 2004 12:00:10 -0600, "RZ"
wrote:

Now that I have your attention.....when ever the shower/tub is
being used,
and either a cold or hot water tap is opened elsewhere in the
house, the
unlucky person in the shower/tub gets cool water only...there
is some
mixture of hot and cold, but the water temp drops
significantly....

The copper piping from the hot water tank feeding both
washrooms is
5/8 inch (outside diameter) throughout. Now, before I go out
and purchase a
couple of pressure-equalizing fixture sets and have them
installed, could
increasing the hot water feeder pipes to 7/8 inch solve my
problem? I would
go with cheaper, easier to install poly pipe.

Also, if my problem can only be solved with
pressure-equalizing fixture
sets, are there pressure-equalizing fixtures that have two
taps (hot and
cold) so that I don't have rip out tile and drywall to create
one center
hole.
Thanks


The problem is caused by a pressure drop in the cold water pipe
that
serves as input to the water heater. The pressure of that
incoming
cold water, is what pushes the hot water out. When you turn on
another
faucet or flusgh a toilet, there just isn't enough water volume
to
maintain the pressure. I solved this problem in my house by
replacing
the 1/2" copper with 3/4" from the meter, across the house to
the
opposite side, so that all the branches are supplied from this
3/4
inch pipe and there is now enough water available so that you
can
flush every toilet and turn on all faucets at once and the
shower
remains hot. The difference in capacity between 1/2" and 3/4 "
is
substantial. Visualize a hole the size of a dime and one the
size of a
quarter. I did nothing to the hot water circuits. In my case
the fix
was feasible because the line across the basement was easily
accessible at both ends. I also ran the 3/4" pipe to the
outside
sillcocks, including new valves, and commercial sized hose.
Watering
the garden now takes half as long.

He could also check that the valve on the cold water line to the
heater is fully open.

Bob

Now that I have your attention.....when ever the shower/tub is being used,
and either a cold or hot water tap is opened elsewhere in the house, the
unlucky person in the shower/tub gets cool water only...there is some
mixture of hot and cold, but the water temp drops significantly....

The copper piping from the hot water tank feeding both washrooms is
5/8 inch (outside diameter) throughout. Now, before I go out and purchase a
couple of pressure-equalizing fixture sets and have them installed, could
increasing the hot water feeder pipes to 7/8 inch solve my problem? I would
go with cheaper, easier to install poly pipe.

Also, if my problem can only be solved with pressure-equalizing fixture
sets, are there pressure-equalizing fixtures that have two taps (hot and
cold) so that I don't have rip out tile and drywall to create one center
hole.
Thanks

"RZ" wrote in message ...
Now that I have your attention.....when ever the shower/tub is being used,
and either a cold or hot water tap is opened elsewhere in the house, the
unlucky person in the shower/tub gets cool water only...there is some
mixture of hot and cold, but the water temp drops significantly....

The copper piping from the hot water tank feeding both washrooms is
5/8 inch (outside diameter) throughout. Now, before I go out and purchase a
couple of pressure-equalizing fixture sets and have them installed, could
increasing the hot water feeder pipes to 7/8 inch solve my problem? I would
go with cheaper, easier to install poly pipe.

Also, if my problem can only be solved with pressure-equalizing fixture
sets, are there pressure-equalizing fixtures that have two taps (hot and
cold) so that I don't have rip out tile and drywall to create one center
hole.
Thanks

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