Noritz N-0931M-DV Installation Manual

Also see for N-0931M-DV: Field manual Service manual

Contents

27B-1. Example of Recirculation with a Multi-SystemThis system will make hot water more quickly available to remote fixtures.The pump will circulate water through the loop until the entire loop is warm, and then the systemcontroller will turn off the pump until the loop cools down.G(1 1/4"-2")(3/4"-1 1/4")Hot WaterSupplyCirculation Pump 2(If Necessary)Circulation Pump 1System select connectorConnect to the "Recirculation System"connector. Remote ControllerPump Connection Wire (for pumps> 85 W, use an external relay)When installing 2 pumps in parallel* Set dipswitch 3 to "OFF".(See SC-201-6M Installation Manual)Gas PipeHot Water Return Line*Size the water supply piping toallow for maximum flow ratesof the units.Hot Water(1 1/4"-2")Water supply* Also disconnect this connector on units 2-6Disconnect this ConnectorExpansionTankUnit 6 Unit 2 Unit 1System Controller* Size the pump to provide at least 2 GPM @ 10 feet of head + piping losses through the system.Check the maintenance monitors on the unit to make sure the pump is providing adequate flow.• Make sure that the flow rate is not greater than 4 ft./sec.(3/4”: 5 GPM, 1 1/4”: 13 GPM)If the flow is too low, the recirculation loop temperature will not be warm enough, if the flow is toohigh, the lifetime of the unit will be reduced.* If there are multiple circulation loops, try to make the flow rate .75-1.25 GPM in each loop.* Use copper or stainless water piping for the entire system.