Water heater with integrated building recirculation control

A hot water circulation system comprising:

• a water heater having an inlet and an outlet;
• a storage tank having a tank inlet configured to be fluidically coupled to a water source, a recovery inlet fluidically coupled to the water heater outlet, a recovery outlet fluidically coupled to the water heater inlet, and a tank outlet configured to be coupled to a plumbing network;
• a recovery pump fluidically coupled to the water heater outlet;
• a building recirculation pump, having an inlet and an outlet, wherein the building recirculation pump is configured to be fluidically coupled to the tank inlet, wherein the inlet of the building recirculation pump is configured to be coupled to an outlet of the plumbing network;
• a first temperature sensor disposed in a location downstream of the water heater outlet;
• and
• a second temperature sensor configured to measure a temperature about the building recirculation pump;
• a building recirculation controller;
• wherein the recirculation controller is configured to receive a heater output temperature from the first temperature sensor, and a recirculation temperature from the second temperature sensor;
• wherein the recirculation controller is configured to control a building recirculation pump based on the heater output temperature and the recirculation temperature.

A method of providing hot water, the method comprising:

• receiving an input to activate a building recirculation pump to circulate water from a storage tank through a hot water recirculation loop in a plumbing network of a building;
• receiving a heater output temperature from a first temperature sensor, wherein the first temperature sensor is disposed downstream of a water heater output of a water heater;
• receiving a recirculation temperature from a second temperature sensor, wherein the second temperature sensor is disposed about the building recirculation pump at a return pipe of the hot water recirculation loop of the plumbing network of the building;
• comparing the recirculation temperature to a comparison value that is calculated based on the heater output temperature;
• maintaining operation of the building recirculation pump upon a determination that the recirculation temperature is less than the comparison value;
• turning off the building recirculation pump upon a determination that the recirculation temperature is at least at the comparison value;
• receiving a storage tank temperature of the storage tank from a third temperature sensor;
• and
• circulating water between the water heater and the storage tank with a recovery pump based on the heater output temperature and the storage tank temperature.