# US 11,441,788 B2 · Method and system for determining hot water use by using temperature gap

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- Number: US 11,441,788 B2
- Document ID: US11441788B2
- Status: Granted
- Kind: B2
- Application number: 16/410,535
- Filed: 2019-05-13
- Published: 2019-11-14
- Granted: 2022-09-13
- Earliest claimed: 2018-05-11
- Assignees: Kyungdong Navien Co., Ltd.
- Applicants: Kyungdong Navien Co., Ltd.
- Inventors: Changheoi Hu; Euneok Lee
- Web page: https://patentgrep.com/patent/US11441788B2

## CPC

- F24D 19/1066: {for the combination of central heating and domestic hot water}
- F24H 15/212: Temperature of the water
- F24H 15/215: before heating
- F24H 15/269: Time, e.g. hour or date
- F24H 15/281: Input from user
- F24H 15/36: of burners
- G01K 1/14: Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
- G01K 2201/00: Application of thermometers in air-conditioning systems
- F24D: DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR (using steam or condensate extracted or exhausted from steam engine plants for heating purposes F01K17/02)
- F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22)
- G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00)

## Abstract

According to an aspect of the present disclosure, there is disclosed a method of determining the use of hot water performed in a system including a water heater and an air handler. The method includes: sensing a temperature of influent flowing into the water heater; sensing a temperature of effluent flowing out of the air handler; calculating a temperature difference between the temperature of the influent and the temperature of the effluent; and determining whether hot water is used by calculating whether the temperature difference is greater than a predetermined value.

## Claims

### Claim 1

A method of determining the use of hot water performed in a system including a water heater and an air handler, the method comprising:
sensing a temperature of influent flowing into the water heater;
sensing a temperature of effluent flowing out of the air handler;
calculating a temperature difference between the temperature of the influent and the temperature of the effluent; and
determining whether hot water is used by calculating whether the temperature difference is greater than a predetermined value.

### Claim 2 (depends on 1)

The method of claim 1, wherein the temperature of the influent and the temperature of the effluent are sensed after a predetermined time has elapsed since the water heater was burned for heating.

### Claim 3 (depends on 1)

The method of claim 1, wherein the determining comprises:
determining that hot water is being used when the temperature difference is greater than the predetermined value.

### Claim 4 (depends on 3)

The method of claim 3, wherein the determining comprises:
determining that the use of hot water is stopped when the temperature difference between the sensed temperature of the influent and the sensed temperature of the effluent is less than the predetermined value.

### Claim 5

A hot water usage determining system comprising:
a water heater;
a first temperature sensor configured to sense a temperature of influent flowing into the water heater;
an air handler configured to receive heating water from the water heater for heating and to discharge effluent after heat exchange;
a second temperature sensor configured to sense a temperature of the effluent, and
a controller communicable with the first temperature sensor and the second temperature sensor;
wherein the controller calculates a temperature difference between the sensed temperature of the influent and the sensed temperature of the effluent, and determines whether hot water is used by calculating whether the calculated temperature difference is greater than a predetermined value.

### Claim 6 (depends on 5)

The hot water usage determining system of claim 5, wherein the second temperature sensor is formed in a water outlet pipe through which the effluent flows.

### Claim 7 (depends on 5)

The hot water usage determining system of claim 5, wherein the second temperature sensor is formed in a water return pipe through which the effluent flows into the water heater again.

### Claim 8 (depends on 5)

The hot water usage determining system of claim 5, wherein the controller determines that hot water is being used when the calculated temperature difference is greater than the predetermined value.

### Claim 9 (depends on 8)

The hot water usage determining system of claim 8, wherein the controller determines that the use of hot water is stopped when the calculated temperature difference between the sensed temperature of the influent and the sensed temperature of the effluent is less than the predetermined value.