Re: Controlling Hot Water Recirculation Pumps

["CWatters" <colin.watters@xxxxxxxxxxxxxxxxxxxxxxxxx>]

"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?

On many systems there is no timer. The loop runs continuously. You can get a
timer added easily.

> (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?

On my system I've added a timer and a pipe mounted thermostat. The timer
turns the loop off at night. The pipe stat is clamped to the pipe where the
hot loop returns to the hot water tank. It turns off the pump during the day
once the hot water has gone around the loop an heated the return. Eventually
the loop cools again and the pump restarts. The pipe stat is overkill
really. A system is perfectly ok without.

> (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?

These recirculating pumps are quite low power and are designed to run
continuously. The power should be written on it somewhere.  I guess you
could use an appliance module to control it and switch it off at night.
Definitly overkill though!