Reactive Energy Storage for Instantaneous Hot Water Applications

Abstract

Systems and methods are directed to water heater systems, including combi boilers and instantaneous water heaters, for initiating pre-heat and energy savings operations. Embodiments of the present invention can include at least one heat exchanger configured to heat water; and a control system in communication with the at least one heat exchanger. The control system can be configured to at least determine an expected flow demand for hot water; sense water temperature at one or more locations, including at a domestic hot water outlet; determine an end to the expected flow demand for hot water; upon receiving an indication to end the flow of hot water, initiate a recovery demand determination; and initiate a pre-heat operation based on the recovery demand determination.

What is claimed is: 
     
         1 . A water heater system, comprising:
 at least one heat exchanger configured to heat water;   a control system configured to at least:
 determine an expected flow demand for hot water; 
 sense water temperature at one or more locations within the water heater system using the plurality of temperature sensors, wherein a first temperature sensor senses a temperature of heated water at the heated domestic hot water outlet; 
 determine an end to the expected flow demand for hot water; 
 upon receiving an indication to end the flow of hot water, initiate a recovery demand determination; and 
 initiate a pre-heat operation based on the recovery demand determination. 
   
     
     
         2 . The water heater system of  claim 1 , wherein the water heater system is a combi boiler or an instantaneous water heater. 
     
     
         3 . The water heater system of  claim 1 , wherein the recovery demand determination is based on an expected recovery temperature threshold or a pattern of usage, where the pattern of usage analyzes water demand based on at least one of a time of day, a demand frequency, an average hot water use over time, anticipated usage, and historic usage. 
     
     
         4 . The water heater system of  claim 1 , wherein the recovery demand determination comprises:
 estimating an anticipated demand based on the expected recovery temperature threshold or the pattern of usage ; and   determining whether to initiate a heating operation based on the anticipated demand.   
     
     
         5 . The water heater system of  claim 4 , wherein the recovery demand determination initiates the pre-heat operation to heat a volume of water to meet the anticipated demand. 
     
     
         6 . The water heater system of  claim 4 , wherein the pre-heat operation causes one or both of the first heat exchanger and second heat exchanger to heat a volume of water based on the anticipated demand. 
     
     
         7 . The water heater system of  claim 4 , wherein the recovery demand determination reduces an amount of time required for the water temperature to reach a set point for a subsequent demand. 
     
     
         8 . A method, comprising:
 determining an expected flow demand for hot water;   sensing water temperature, using a plurality of temperature sensors, at one or more locations within a water heater system comprising at least one heat exchanger, wherein a first temperature sensor senses a temperature of heated water at a heated domestic hot water outlet;   determining an end to the expected flow demand for hot water;   initiating a recovery demand determination; and   initiating a pre-heat operation based on the recovery demand determination.   
     
     
         9 . The method of  claim 8 , wherein the at least one heat exchanger is part of a combi boiler or an instantaneous water heater. 
     
     
         10 . The method of  claim 8 , wherein the recovery demand determination is based on either an expected recovery temperature threshold or a pattern of usage, wherein the pattern of usage analyzes water demand based on at least one of a time of day, a demand frequency, an average hot water use over time, anticipated usage, and historic usage. 
     
     
         11 . The method of  claim 8 , wherein the recovery demand determination comprises:
 estimating an anticipated demand based on the pattern of usage; and   determining whether to initiate a heating operation based on the anticipated demand.   
     
     
         12 . The method of  claim 11 , wherein the recovery demand determination initiates the pre-heat operation to heat a volume of water to meet the anticipated demand. 
     
     
         13 . The method of  claim 11 , wherein the pre-heat operation causes one or both of the first heat exchanger and second heat exchanger to heat a volume of water based on the anticipated demand. 
     
     
         14 . The method of  claim 11 , wherein the recovery demand determination reduces an amount of time required for the water temperature to reach a set point for a subsequent demand.