SYSTEMS AND METHODS FOR FAULT DETECTION USING SMART VALVES

• US 20150233597A1
• Filed: 04/29/2015
• Published: 08/20/2015
• Est. Priority Date: 12/17/2013
• Status: Active Grant

• Current Assignee: Belimo Holding AG
• Original Assignee: Optimum Energy LLC
• Inventors: Dempster, Ian Robert, Erpelding, Benjamin Paul, Hartman, Thomas Bennett, MacNeill, Chelsey Ann
• Granted Patent: US 10,465,925 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24F 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/56 Remote control
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 11/83 by controlling the supply of heat-exchange fluids to heat-exchangers
• CPC Class Codes: F24F 11/84 using valves
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2140/20 Heat-exchange fluid temperature
• CPC Class Codes: F24F 3/044 Systems in which all treatment is given in the central station, i.e. all-air systems
• CPC Class Codes: F24F 3/08 with separate supply and return lines for hot and cold heat-exchange fluids i.e. so-called "4-conduit" system
• CPC Class Codes: F24H 3/08 by tubes
• CPC Class Codes: F24H 9/2064 for air heaters
• CPC Class Codes: G01K 13/02 for measuring temperature of moving fluids or granular materials capable of flow
• CPC Class Codes: G01K 13/024 of moving gases
• CPC Class Codes: G01K 13/026 of moving liquids

Abstract

An air handler unit (AHU) in communication with a building automation system (BAS) or through direct programming of one or more smart valves within the AHU operates to meter an amount of water that flows through a coil in the AHU. In one embodiment, the BAS transmits a temperature setpoint signal to the smart valve and allows the smart valve to control its valve position without additional input from the BAS. In another embodiment, the AHU includes a master smart valve and a second valve. The BAS provides the temperature setpoint signal to the master smart valve, which in turn provides another temperature setpoint signal to the second valve. The second valve may take the form of a slave smart valve or a slave non-smart valve.

Claims

1. A fault detection system for detecting a lack of air flow in an air handler unit, the fault detection system comprising:

a coil located in an air stream of the air handler unit, the coil configured to operate as a conduit for process fluid in the system;

air temperature sensors located in an air stream of the air handler unit, one temperature sensor located to determine an air temperature of air upstream of the coil and another temperature sensor located to determine an air temperature downstream of the coil;

liquid temperature sensors located to determine a liquid temperature entering the coil and to determine a liquid temperature exiting the coil;

a smart valve having a controller in communication with the liquid temperature sensors and at least one of the air temperature sensors, the controller operable to utilize the measured temperatures for a period of time to determine whether the air handler unit is experiencing a lack of air flow; and

a notification device in communication with the controller of the smart valve,

wherein determining the lack of air flow, the smart valve activates the notification device and the controller of the smart valve mitigates an energy loss by changing a valve position of a smart valve actuator to fully closed or partially closed.

2. The fault detection system of claim 1, wherein the smart valve provides a signal to a computing system regarding the lack of air flow.

3. The fault detection system of claim 1, wherein the notification device provides a visual light proximate the smart valve.

4. The fault detection system of claim 1, wherein the smart valve communicates with a building automation system.

5. The fault detection system of claim 4, wherein determining the lack of air flow includes determining with the building automation system is disabled.

6. The fault detection system of claim 4, wherein determining the lack of air flow includes the building automation system operating to disable a fan within the air handler unit.

7. The fault detection system of claim 1, wherein the coil is a heating coil, a cooling coil, or both a heating and a cooling coil.

8. A fault detection system for detecting a flow restriction in an air handler unit, the fault detection system comprising:

a coil located in an air stream of the air handler unit, the coil configured to operate as a conduit for process fluid in the system, the coil having a plurality of design parameters;

air temperature sensors located in an air stream of the air handler unit, one temperature sensor located to determine an air temperature of air upstream of the coil and another temperature sensor located to determine an air temperature downstream of the coil;

liquid temperature sensors located to determine a liquid temperature entering the coil and to determine a liquid temperature exiting the coil;

a smart valve having a controller in communication with the liquid temperature sensors and at least one of the air temperature sensors, the controller operable to use the measured air temperature downstream of the coil and a valve actuator position to determine whether the coil is operating at a reduced capacity; and

a notification device in communication with the controller of the smart valve.

9. The fault detection system of claim 8, wherein the controller is configured to modulate the valve actuator position to minimize an energy loss of the air handler unit until the reduced capacity situation is rectified.

10. The fault detection system of claim 8, wherein the controller is configured to modulate the valve actuator position to overflow the liquid supplied to the coil.

11. The fault detection system of claim 10, wherein the overflow of the liquid supplied to the coil mitigates a performance loss of the air handler unit for a designated period of time.

12. The fault detection system of claim 11, wherein the designated period of time is an amount of time for the reduced capacity situation to be rectified.