Systems and methods for operating and monitoring dehumidifiers

• US 8,572,994 B2
• Filed: 04/26/2010
• Issued: 11/05/2013
• Est. Priority Date: 04/27/2009
• Status: Active Grant

• Current Assignee: Legend Brands, Inc. (RPM International Incorporated)
• Original Assignee: Dri-Eaz Products Incorporated (RPM International Incorporated)
• Inventors: Pendergrass, Robert, Miller, Matthew, Schnelle, Tom, White, Larry
• Primary Examiner(s): NORMAN, MARC E
• Application Number:
  US12/767,526
• Publication Number:
  US 20100269526A1
• Time in Patent Office: 1,289 Days
• Field of Search: 621/761, 621/766, 621/86, 236/44.A, 236/44.C
• US Class Current: 62/176.6
• CPC Class Codes: B01D 53/265 by refrigeration (condensation)
• CPC Class Codes: F24F 11/0008 for air-humidification F24F11/30 takes precedence
• 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 11/65 for selecting an operating mode
• CPC Class Codes: F24F 11/74 for controlling air flow rate or air velocity
• CPC Class Codes: F24F 11/77 by controlling the speed of ventilators
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

Systems and methods of automatically operating dehumidifiers in response to dehumidifier operating conditions are disclosed herein. A method of operating a dehumidifier configured in accordance with one embodiment includes directing air flow through the dehumidifier at a first volumetric flow rate while the dehumidifier is operating at a first operating condition. The method further includes changing the first volumetric flow rate to a second volumetric flow rate when the first operating condition of the dehumidifier changes to a predetermined second operating condition.

Claims

1. A method of controlling air flow through a dehumidifier having an air mover and a moisture removal device, the method comprising:

operating the air mover at a first speed to direct air flow into thermal contact with the moisture removal device while ambient air surrounding the dehumidifier is at a first ambient condition that includes a first humidity, wherein air flow through the dehumidifier has a first dwell time at the moisture removal device with the air mover operating at the first speed;

sensing a change from the first ambient condition to a second ambient condition that includes a second humidity less than the first humidity and below a threshold humidity value; and

in response to the change, automatically operating the air mover at a second non-zero speed that is slower than the first speed to increase the first dwell time of air flow at the moisture removal device to a second dwell time.

2. The method of claim 1 wherein sensing the change includes measuring one or more of a dry-bulb temperature, a wet-bulb temperature, a dew-point temperature, a relative humidity, and a specific humidity of the ambient air.

3. The method of claim 1 wherein sensing the change includes sensing a decrease in a temperature of the moisture removal device from a first temperature to a second temperature, and wherein the decrease in the temperature of the moisture removal device corresponds to a decrease in humidity of the ambient air surrounding the dehumidifier.

4. The method of claim 1 wherein operating the air mover at the first and second speeds to direct air flow includes directing air flow into thermal communication with an evaporator.

5. The method of claim 1 wherein the threshold humidity value is less than about 45 grains per pound (GPP).

6. A method of operating a dehumidifier, the method comprising:

moving air flow through the dehumidifier at a first volumetric flow rate while an operating condition of the dehumidifier includes a first humidity value; and

automatically decreasing from the first volumetric flow rate to a second non-zero volumetric flow rate in response to the operating condition of the dehumidifier decreasing beyond a threshold humidity value from the first humidity value to a second humidity value less than the first humidity value.

7. The method of claim 6 wherein:

moving air flow through the dehumidifier at the first volumetric flow rate includes driving an air mover in the dehumidifier at a first speed; and

changing the first volumetric flow rate includes driving the air mover at a second speed that is slower than the first speed.

8. The method of claim 6 wherein:

moving air flow through the dehumidifier at the first volumetric flow rate includes directing air flow into thermal contact with a moisture removal device in the dehumidifier, with the air flow having a first dwell time at the moisture removal device; and

changing from the first volumetric flow rate to the second non-zero volumetric flow rate includes directing air flow into thermal contact with the moisture removal device, with the air flow having a second dwell time that is greater than the first dwell time.

9. The method of claim 6 wherein:

moving air flow through the dehumidifier at the first volumetric flow rate while the operational condition of the dehumidifier includes the first humidity value includes moving air flow at the first volumetric flow rate while a moisture removal device of the dehumidifier is operating at a first temperature; and

changing from the first volumetric flow rate to the second non-zero volumetric flow rate includes reducing the first volumetric flow rate to the second volumetric flow rate in response to the temperature of the moisture removal device decreasing to a second temperature.

10. The method of claim 6 wherein:

moving air flow through the dehumidifier at the first volumetric flow rate while the operating condition of the dehumidifier includes the first humidity value includes directing air flow while air flow has a first specific humidity at an outlet of the dehumidifier; and

changing from the first volumetric flow rate to the second non-zero volumetric flow rate includes reducing the first volumetric flow rate to the second volumetric flow rate in response to the specific humidity of air flow decreasing to a second specific humidity at the outlet of the dehumidifier.

11. The method of claim 6 wherein the threshold humidity value is less than about 45 GPP.

12. A method of controlling air flow through a dehumidifier, the method comprising:

moving air flow through the dehumidifier at a first volumetric flow rate while a humidity of ambient air surrounding the dehumidifier has a first humidity value;

determining a change in the humidity from the first humidity value to a second humidity value that is less than the first humidity value and below a threshold humidity value; and

in response to the change in humidity, automatically moving air flow through the dehumidifier at a second non-zero volumetric flow rate that is less than the first volumetric flow rate.

13. The method of claim 12 wherein moving air flow through the dehumidifier at the second volumetric flow rate includes increasing a dwell time of air flow at a moisture removal device of the dehumidifier.

14. The method of claim 12 wherein:

moving air flow at the first volumetric flow rate includes directing air flow through the dehumidifier with an impeller rotating at a first rotational speed; and

moving air flow at the second volumetric flow rate includes directing air flow with the impeller rotating at a second rotational speed that is less than the first rotational speed.

15. The method of claim 12 wherein the threshold humidity value is less than about 45 GPP.

16. A method of increasing performance of a dehumidifier, the method comprising:

rotating an air mover in the dehumidifier at a first speed to move air flow through the dehumidifier at a first volumetric flow rate;

monitoring a humidity of ambient air surrounding the dehumidifier; and

in response to a decrease of the humidity of the ambient air below a predetermined humidity level, automatically rotating the air mover at a second speed that is slower than the first speed to move air flow through the dehumidifier at a second volumetric flow rate that is less than the first volumetric flow rate.

17. The method of claim 16 wherein:

rotating the air mover at the first speed removes moisture from the air flow at a moisture removal rate; and

rotating the air mover at the second speed at least maintains the moisture removal rate at the predetermined humidity level.

18. The method of claim 16 wherein:

rotating the air mover moves air flow across a moisture removal device in the dehumidifier; and

monitoring the humidity includes monitoring a temperature of the moisture removal device, wherein the temperature of the moisture removal device corresponds to the humidity of the ambient air.

19. The method of claim 16 wherein the predetermined humidity level is less than about 45 GPP.

20. A dehumidifier comprising:

a moisture removal device positioned along an air flow path to remove moisture from air flow through the dehumidifier;

an air mover positioned to direct air flow through the dehumidifier along the air flow path and into thermal communication with the moisture removal device; and

a controller coupled to the air mover, wherein the controller is configured to automatically operate the air mover to direct air flow at a first volumetric flow rate while the dehumidifier is at a first operating condition that corresponds to a first humidity and a reduced second volumetric air flow rate in response to a change from the first operating condition to a second operating condition corresponding to a second humidity below a threshold humidity value.

21. The dehumidifier of claim 20, further comprising a sensor that measures a temperature of the moisture removal device, and wherein the first operating condition is a first temperature of the moisture removal device and the second operating condition is a second temperature of the moisture removal device.

22. The dehumidifier of claim 20 wherein the moisture removal device is an evaporator and the air mover is an impeller.

23. The dehumidifier of claim 20 further comprising a computer readable medium storing instructions thereon that, when executed by the controller, operate the air mover at the first and second speeds.

24. The dehumidifier of claim 20 wherein the threshold humidity value is less than about 45 GPP.