can you recommend a recirculating pump?
we are building a home and will be using 2 rinnai tankless water heaters that will be pigtailed for our whole house. Our engineering plans call for a recirculating pump to push hot water to the rooms faster. The pump turns on automatically through a sensor whenever the lights in the bedrooms turn on. I am supposed to buy all appliances for our build, but have no idea where to find such a pump and sensor. Is this setup pretty common? Can you recommend some brands of pump and sensors for me to look at? thank you very much!