I posted the message below a couple days ago but with a different
subject.

Since this involves metal plumbing I figger it's probably OK to post
my questions. Because of the way my house is plumbed it takes a long
time for the water to get hot at a few fixtures. I could put little
water heaters at these fixtures but that would require running power
to the fixtures. Though this could be done it wouldn't be easy. I
looked at two types of recirculating systems and both are lacking. One
relys on a thermostatic valve opening up between the hot and cold
pipes when the hot side cools enough. For the system to work a pump
must be operating , to keep the hot side at a higher pressure. The
other system I looked at requires running wires from each fixture. The
wires power a solenoid valve and provide a signal to turn on a pump.
But that would require running wire which as already stated isn't that
easy. I'm wondering if maybe a check valve and a differential switch
could be used to turn on the pump when the thermostatic valve opens.
The valve doesn't require power and each fixture can have its own
valve. Or just one valve can be installed at the furthest fixture.
Advice anyone?
Thanks,
Eric

P.S.
I don't want to run wires to the fixtures, it's a big hassle and I am
looking for a solution to avoid it. I think a pressure differential
switch may be the solution. If I wanted to use a timer I wouldn't have
asked about the switch. A timer is not a good solution.

wrote in message
...
I posted the message below a couple days ago but with a different
subject.

Since this involves metal plumbing I figger it's probably OK to post
my questions. Because of the way my house is plumbed it takes a long
time for the water to get hot at a few fixtures. I could put little
water heaters at these fixtures but that would require running power
to the fixtures. Though this could be done it wouldn't be easy. I
looked at two types of recirculating systems and both are lacking.
One
relys on a thermostatic valve opening up between the hot and cold
pipes when the hot side cools enough. For the system to work a pump
must be operating , to keep the hot side at a higher pressure. The
other system I looked at requires running wires from each fixture.
The
wires power a solenoid valve and provide a signal to turn on a pump.
But that would require running wire which as already stated isn't
that
easy. I'm wondering if maybe a check valve and a differential switch
could be used to turn on the pump when the thermostatic valve opens.
The valve doesn't require power and each fixture can have its own
valve. Or just one valve can be installed at the furthest fixture.
Advice anyone?
Thanks,
Eric

P.S.
I don't want to run wires to the fixtures, it's a big hassle and I
am
looking for a solution to avoid it. I think a pressure differential
switch may be the solution. If I wanted to use a timer I wouldn't
have
asked about the switch. A timer is not a good solution.

Your specification is vague and incomplete and forces us to make
assumptions.
Forget the hardware for a moment, what are you trying to achieve from
the user's perspective?

For example, is the recirculating pump triggered by the water cooling,
by someone at the remote faucet, or by someone going to the remote one
because the more convenient bathroom is busy?

The last may be the simplest to implement if you can locate the pump
button on short wiring at a traffic choke point like the stairs. If
they forget they have to wait a little longer, or wash in room temp
water.
-jsw