Control system for a water heater

Abstract

A multi-function controller for a water heater is advanced comprising a control panel and a plurality of sensors that monitor a variety of functions that impact the operation of a water heater. A flammable gas sensor, placed in proximity to the air intake, detects the presence of an unsafe concentration of gas and issues a signal to the control panel, which subsequently discontinues the operation of the burners. Detection of a blocked vent pipe is achieved by a carbon monoxide sensor placed near the draft hood. The control panel is equipped with circuitry which monitors usage of the heater for a specified time period to develop a pattern of use. Subsequent to the monitoring period, the controller will activate the burners a predetermined time prior to an anticipated period of high use. During periods of low use, the controller will decrease the temperature to which the water is to be heated, thereby resulting in a more efficient heater. Non-volatile memory records data from the sensors so that the operation status of the heater may be ascertained subsequent to a power outage. The control panel contains a plurality of visual alarms, each of which corresponds to a sensor. Consequently, repair and maintenance are simplified because the cause of a malfunction is quickly recognized.

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates generally to water heaters. In particular, the present invention relates to the control of water heaters for proper operation and safety.2. Discussion of BackgroundMuch of the world has come to depend on having hot water on demand for bathing, laundering, and cooking. Usually this demand is met by water heaters. Water heaters come in two basic types: storage water heaters, which heat water in a tank for use when there is a demand, and instantaneous water heaters, which heat water as it is being drawn through the heater.Controlling the water heater begins with the temperature of the water it supplies. More specifically, being able to heat the source water to a desired temperature means being able to select that temperature from a range of temperatures and then controlling the water heater so that it does, in fact, heat the water to that temperature, regardless of changes in the many parameters that will...

AI Technical Summary

Benefits of technology

According to its main features and briefly stated, the present invention is a multiple function, solid state control system for a water heater. The control system comprises a control panel having a microprocessor, mounted to the exterior of the water heater, in electrical connection with a flammable gas sensor, positioned proximate to the air intake. Upon detecting a preselected concentration of a flammable gas, the sensor will issue a signal to the control panel which will prevent ignition of the burners, or shut them off if already in operation. A carbon monoxide sensor, positioned proximate to the draft hood, detects the presence of an unacceptable level of carbon monoxide, indicative of a blocked vent pipe, and also sends a signal to the microprocessor which will prevent, or discontinue, the operation of the burners. Both the flammable gas and carbon monoxide detector contain self-diagnostic circuitry which assures proper sensor operation. In addition, circuitry within the microprocessor monitors the service life of the sensors and will cause an alarm to be initiated when the sensors require replacement.

A major feature of the present invention is the placement of the flammable gas sensor, proximate to the air intake channel. Placement of the sensor in this region enables the sensor to sense the presence of a dangerous concentration of flammable gas and issue a signal to the controller prior to the gas reaching the flame. Consequently, the controller is capable of deactivating or preventing the operation of the burners prior to an explosion.

Another major feature of the present invention is the use of a carbon monoxide detector to determine the blockage of the vent pipe. A vent pipe can become blocked by birds, improper roof installation, rusted pipes, or the like. When this occurs, combustion gases back up below the exit to the flue and are referred to as "spillage" gases. These spillage gases contain an unsafe concentration of carbon monoxide. The gases will escape from both the ductwork and burner area of the water heater and enter the surrounding area, causing the danger of injuries and possibly death to individuals in the vicinity. By providing a carbon monoxide sensor, it is possible to detect the presence of an excessive concentration of carbon monoxide and deactivate the burners before the carbon monoxide concentration reaches a hazardous level.

Still another feature of the present invention is safety. The present invention centrally monitors a number of operational conditions that impact safety. Upon issuance of a signal that any of these conditions are outside operating parameters or are failing to function, the controller will halt the operation of the burners and emit an audio and / or visual alarm which details the type of malfunction that has occurred. Consequently, the danger of an explosion, escape of harmful gases, and other hazards associated with the operation of a water heater are minimized. Moreover, by indicating the type of malfunction that has occurred, diagnosis and repair is simplified.

Problems solved by technology

In addition, circuitry within the microprocessor monitors the service life of the sensors and will cause an alarm to be initiated when the sensors require replacement.

Images