Re: Controlling Hot Water Recirculation Pumps

["Jeff Volp" <JeffVolp@xxxxxxx>]

I installed one of those Grudfos pumps here.  The master bedroom and laundry
are a long run from the hot water heater.  In this desert climate, I hated
to dump that much water down the drain waiting for the water to warm up.
Our schedule is variable, so we may need hot water any time of the day.

I changed the runs to two complete loops which service opposite ends of the
house, The Grudfos pumps both loops.  A gate valve in the return balances
both so they heat up at the same speed.  The pump runs for 75 seconds every
15 minutes, just long enough for freshly heated water to purge the line.
All piping is well-insulated so there is little decrease in temperature over
that interval.  I probably could stretch it out to 20 minutes or even a half
hour by allowing more variation in temperature.

Rather than hearing that clack clack every 15 minutes, I run the Grudfos off
an old BSR X10 lamp module.  Obviously, it is only sent ON and OFF commands
from the Ocelot.  It has worked fine for almost 4 years now.

Regarding a timer or possible temperature sensor, check if there is any
other wiring or a dial on the pump.  If it just has a simple wire connection
that connects to 120VAC, it probably runs 24/7

Jeff

"David White" <whitedavidp@xxxxxxxxxxx> wrote in message
news:76udnYZFN5WKzOzbnZ2dnUVZ_gadnZ2d@xxxxxxxxxxxxxx
> Hello. I just bought a new home that has a recirculation pump located near
> the hot water heater. I am new to all this so I have some questions:
>
> (a) I have looked online and see some of these pumps have timers attached
> so they operate only during expected usage times (not between midnight and
> 5am). Mine does not have one that I can see. Are these always attached
> directly to the pump body or can the timer be located elsewhere? If
> elsewhere, where might this be?
>
> (b) I have read that some of these systems incorporate a temperature
> switch somewhere that shuts off the pump when a pre-set temp is reached at
> some point in the line. What are the signs that mine has such a switch?
>
> (c) Even with a timer as in (a) above it seems potentially very wasteful
> and hard on the pump for it to run continuously as we are not big hot
> water users generally. So is there some simple way - ideally using X-10,
> Active Home, CMA-11 (I think that's it), and simple macros (no running
> computer needed) which I already use - to control this pump mechanism at a
> more granular level?
>
> Thanks,
>
> David