I installed a Noritz NRC1111DVNG with a Redytemp recirc pump at the water heater location. It is controlled by timer until the thermostat at the furthest sink warms up. During the rest of the day when the timer is off, manual rocker switches (kitchen and two bathrooms) will trigger the pump to heat the pipes.

Noritz has an internal relay in this hot water heater that they claim is the preferred method of controlling the recirculation pump. I don't know anything about it, and am unsure how this could be an improvement on my Redytemp setup. If, for example, Noritz had an input (from the timer or switch) as well as an output (to the pump), I could see the possibility of cold water sandwich avoidance by firing the burner until the water was hot, and THEN turning on the pump. A trick that is not possible when the burner is triggered by water flow from a faucet.

But I don't see an input in their manual, and there is little to no description of the logic controlling this relay.

Does anybody know anything about Noritz's recirc pump control, and if it can be used in conjunction with my existing control to improve it?

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