Controlling Hot Water Recirculation Pumps

[David White <whitedavidp@xxxxxxxxxxx>]

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