The Tank › Hot water recirculating systems vs. booster heaters. › Reply To: Hot water recirculating systems vs. booster heaters.
I have a Watts model 500800 after market recirc pump. The instructions say to plumb it on the WH hot line. But pump seals prefer cold water vs. hot. I built a heat trap on the cold line and installed the pump there so hot water cannot get to the pump. When the pump runs, it has to push cold water in so hot water has to leave. It works fine. There is a thermostatically controlled check valve under the farthermost sink. If you had to go in two completely different directions, I would think you could order a second valve. There is a timer on the motor which can be set for 15 minute increments. During awake hours, I run 15 on and 15 off. If I would ever insulate the pipes, I could probably go 15 on 30 off or more. I turn it off during asleep hours. The only power you need (120 volts) is at the WH.
I have seen these systems and you can buy as many check valves as you need.
So you just put the pump on the inlet side of the heater instead of the outlet side?
What do you think of systems that use a push button or a motion detector that circulate the hot water only when it is needed?? This would eliminate the timer and theoretically only circulate hot water when needed, although you do have to push the button before you need the hot water.
How reliable have the check valves been???