CN101072629A - Single integrated humidity and ventilation control in an hvac system - Google Patents

Abstract

HVAC systems are employed to control the indoor environmental characteristics of a building structure to make it comfortable for its inhabitants. An HVAC system includes one single integrated central control to regulate an indoor temperature level, an indoor relative humidity level and an indoor fresh air level of a building structure during both a heating season and a cooling season. Further, the single integrated central control is operable to selectively activate/deactivate an indoor blower to control a sensible ratio within a building structure. In addition, a protection feature for avoiding condensation on the interior surfaces of the building structure is included as an user selectable option.

Description

Single integrated humidity/ventilation control in heating, ventilation, and air conditioning systems

This application claims priority to US Provisional Application No. 60/537,528, filed January 20, 2004, the disclosure of which is hereby incorporated by reference in its entirety.

technical field

This application relates to indoor central heating, ventilation, and air conditioning (HVAC) systems in which the control of indoor temperature, indoor relative humidity, and indoor fresh air level are combined into a single integrated centralized control device, which is controlled during the heating and cooling seasons The device can be used to manage the indoor environment.

Background technique

HVAC systems are used to control the indoor environmental characteristics of building structures for occupant comfort. A typical HVAC system includes a temperature control device, or thermostat, and one or more humidity control devices called a humidistat.

A thermostat is used as a control device to regulate the temperature in a room. The thermostat senses the actual room temperature and allows the user to input the desired room temperature. As the room temperature deviates from a desired level, the thermostat operates to selectively activate or deactivate the heating unit and/or air conditioner and its associated blower to achieve the user's desired setting.

In addition to temperature control, in order to provide a comfortable indoor environment, the indoor relative humidity of the building is often adjusted. Relative humidity is defined as the ratio of the actual amount of water vapor in the air to the maximum water vapor capacity at a given air temperature. It is known that as the temperature increases, the capacity of the air to hold water vapor in the form of water vapor also increases. Conversely, as the temperature decreases, the capacity of the air to hold water vapor decreases, and any excess water vapor condenses as water on surfaces in contact with the air.

Therefore, during the winter months, the cold outdoor air has a relatively low moisture content, however, the air inside the building structure is usually heated. Depending on the construction quality of a particular building, some of the cool, dry outside air infiltrates into warm interior spaces and is subsequently heated to interior temperatures. This phenomenon effectively reduces the indoor relative humidity and dries the indoor air.

To address this winter dryness or low indoor relative humidity, humidifiers are often used as part of central heating systems. A humidifier brings moisture into the heated air, increasing the relative humidity in the room and is usually controlled by a second control device called a humidistat. The hygrostat senses actual indoor relative humidity and allows the user to set a desired indoor relative humidity level. When the indoor relative humidity falls below a desired level, the hygrostat activates the humidifier to add moisture to the air. Once the desired indoor relative humidity is reached, the hygrostat stops the humidifier.

Conversely, to address high indoor relative humidity, devices known as ventilators are often used. Once the indoor relative humidity exceeds the desired level, the ventilators are activated to bring a controlled amount of outside dry air into the building envelope to lower the indoor relative humidity. In addition, ventilators are used to bring in a controlled amount of outside fresh air to improve indoor air quality. Ventilators are usually controlled by a humidistat. However, the humidistat that controls the ventilator is generally separate from the humidistat that also controls the humidifier.

While it is known to combine temperature control and humidifier control into a single controller (such as a hygrostat), the combination of ventilators usually requires the addition of a second independent humidistat control. Likewise, providing year-round control of all indoor environmental characteristics of a building structure requires the user to interface with at least two control devices to control different functions of the same HVAC system. This can confuse users. Furthermore, functions requiring multiple control devices to control the same HVAC system can sometimes have conflicting results, thus causing the system to operate at a less than optimal performance level.

In summary, controlling indoor environmental characteristics such as indoor temperature, indoor relative humidity, and indoor fresh air level has thus far required the use of multiple control devices, which is not ideal. Therefore, it is desirable to have HVAC systems that integrate temperature, humidity, and ventilation into a single comprehensive centralized control unit.

Contents of the invention

The invention discloses a single comprehensive centralized control device. The single integrated centralized control device can obtain various actual environmental characteristics, such as: indoor temperature, indoor relative humidity and outdoor temperature, which are transmitted to the single integrated centralized control device through various sensors.

In one disclosed embodiment, the single integrated centralized control device has an input structure for the user to input desired indoor environment characteristics, such as: the user's desired indoor temperature during heating, the user's desired indoor temperature during cooling, the user's desired indoor temperature during heating, and the user's desired indoor temperature during heating. The desired indoor relative humidity, the user's desired indoor relative humidity when cooling, and/or the desired indoor fresh air level. Based on various actual environmental inputs and user-desired inputs, a single integrated centralized control device provides comprehensive centralized control of the heating and air-conditioning system (including associated blowers, humidifiers, ventilators) to achieve the user-desired indoor environment characteristic.

During the heating season, that is, when the outdoor temperature drops below the user's desired indoor temperature, the air in the building structure has a tendency to dry out, ie, the indoor relative humidity is low. In this environment, in addition to controlling the actual indoor temperature to achieve the user's desired indoor heating temperature, a single integrated centralized control device is used to actively humidify the indoor air. Active humidification involves the start and stop of balanced humidifiers and/or ventilators. When the actual indoor relative humidity is lower than the user's desired indoor relative heating humidity (this situation usually occurs in the heating season), start the humidifier to add water vapor to the air, and actively increase the actual indoor relative humidity. Conversely, when the actual indoor relative humidity exceeds the user's desired indoor relative heating humidity, the ventilator is activated to bring cool, dry, and fresh outdoor air into the building structure, effectively reducing the actual indoor relative humidity.

During the cooling season, that is, when the outdoor temperature exceeds the user's desired indoor temperature, the air within the building structure has a tendency to become humid or humid, ie, the indoor relative humidity is high. In this environment, a single integrated centralized control unit is used to actively dehumidify the room air in addition to controlling the actual room temperature. Active dehumidification includes adjusting the temperature of the output air generated by the air conditioner and the airflow generated by the blower associated with the air conditioner. When the actual indoor relative humidity exceeds the indoor relative cooling humidity expected by the user (this situation usually occurs in the cooling season), the single integrated centralized control device adjusts the temperature of the air conditioner to be lower than the indoor cooling temperature expected by the user Sets the degree and reduces the airflow generated by the blower associated with the air conditioner. This effectively maintains the actual indoor temperature close to the user's desired indoor cooling temperature while reducing the actual indoor relative humidity. Conversely, when the actual indoor relative humidity is lower than the user's desired indoor relative humidity for cooling, start the ventilator to bring warm, humid, and fresh outdoor air into the building structure, effectively increasing the actual indoor relative humidity .

In addition, during the cooling season, a single comprehensive centralized control device can effectively control the indoor sensible ratio (that is, balance cooling or sensible heat demand and dehumidification or latent heat demand) by selectively adjusting the blower fan. latent demand)) to adjust the indoor airflow. By adjusting the indoor airflow, the air conditioner can transfer different proportions of sensible heat and latent heat capacity to the indoor space. Therefore, if there is a high sensible heat demand (room temperature is difficult to maintain) but no latent heat demand (humidity below desired humidity level), the room airflow is increased to increase the sensible heat ratio of the air conditioning capacity delivered. Conversely, when there is little cooling demand but the humidity is above the desired humidity level, indoor airflow is reduced to reduce the sensible heat ratio.

In another disclosed embodiment, commonly assigned, concurrently A single integrated centralized control unit including protective components (optional by the user) for preventing condensation on building interior surfaces is disclosed in a pending US patent application, the disclosure of which is incorporated herein by reference in its entirety. This option provides automatic adjustment of the desired indoor relative humidity based on actual indoor and outdoor characteristics to avoid condensation on building interior surfaces.

In this embodiment, the user input is a user-selectable heating humidity level entered by the building owner or actual occupant. The occupant selects the heating humidity level from a predetermined range of 1-9, with a default value around the middle, say 5. The selected heating humidity level is then used to determine the single adjustment coefficient (A ^* ). In this embodiment, the centralized control unit converts the user-selected heating humidity level into a single adjustment factor (A ^* ) using a conversion table stored in memory. The single adjustment factor (A ^* ) is then used to calculate the maximum allowable indoor relative humidity based on the user selected heating humidity level.

Occupants typically set the heating humidity level to just below the level that allows condensation to occur. This is done through an iterative process. Occupants selectively increase heating humidity levels until condensation occurs within the building envelope. The occupant then selectively reduces the heating humidity level to just below where condensation occurs. Once the occupant has selected the desired indoor relative humidity to prevent condensation, a centralized control can be used to maintain the actual indoor relative humidity based on the user-selected indoor relative humidity level, continuously adjusting the actual indoor relative humidity to provide varying environmental conditions while simultaneously Prevent condensation.

In yet another disclosed embodiment of the invention, the installer of the HVAC system enters the user input after installation. User input represents building structural characteristics and typically indicates the degree of insulation of the building envelope. User input may be set based on the installer's experience with previous homes of similar quality. In this embodiment, centralized control uses a conversion table to subsequently convert the structural features into the aforementioned single adjustment coefficients (A ^* ). The single adjustment factor (A ^* ) is then used to calculate the maximum allowable indoor relative humidity based on the degree of insulation of the building. Once set by the installer, the HVAC system is used to maintain the actual indoor relative humidity level, constantly adjusting to provide changing environmental conditions to prevent condensation.

These and other features of the present invention can be better understood from the following description and drawings, the following of which is a brief description.

Description of drawings

Figure 1 is a schematic diagram of a building HVAC system.

Figure 2 is a detailed schematic diagram of a building HVAC system including integrated centralized controls for controlling furnaces, air conditioners, humidifiers and ventilators, and blowers.

Figure 3 is a detailed diagram of an example indoor relative humidity input.

Fig. 4 is a graph illustrating active humidification in the heating mode of the integrated centralized control device.

Fig. 5 is a graph illustrating active dehumidification in the cooling mode of the integrated centralized control device.

Fig. 6 is an example of a conversion table.

Fig. 7 is an example of an allowable humidity table.

Fig. 8 is a graph illustrating fresh air control of the integrated centralized control device.

Detailed ways

FIG. 1 illustrates a schematic diagram of a building HVAC system 10 . A single integrated centralized control device 12 may control multiple indoor environmental characteristics based on the actual environmental characteristic E sensed by at least one environmental sensor 14 and user input U input to the user interface 16 by the user. A single integrated centralized control device 12 controls indoor environmental characteristics by selectively activating and/or deactivating at least one device 18 .

FIG. 2 illustrates a detailed schematic diagram of a building HVAC system 10 including a single integrated centralized control device 12 . A single integrated centralized control device 12 receives actual environmental input from multiple sensors. Indoor temperature sensor 20, indoor relative humidity sensor 22, and outdoor temperature sensor 24 may be used to transmit actual indoor temperature input (T _I ), indoor relative humidity input (H _I ), and actual outdoor temperature (T _O ) to a single integrated centralized Control device 12. User interface 16 may be used to receive user input. The user inputs his desired indoor temperature level 26, his desired indoor relative humidity level 28, and his desired fresh air level 30, which includes the user's desired indoor heating temperature level and The indoor cooling temperature level desired by the user, the indoor relative humidity level 28 desired by the user includes the heating humidity level 28A ( FIG. 3 ) desired by the user and the cooling humidity level 28B ( FIG. 3 ) desired by the user.

The user interface 16 communicates the user's desired settings to the single integrated centralized control device 12 . Based on a comparison of user desired settings received from the user interface 16 with actual environmental inputs received from multiple sensors, a single integrated centralized control device 12 can be used to selectively activate and/or deactivate at least one device 18 to control the actual indoor environment. Temperature level, actual indoor relative humidity level and actual indoor fresh air level to achieve user desired settings. In the illustrated embodiment, at least one appliance 18 includes a furnace 18A, an air conditioner 18B, a humidifier 18C, a ventilator 18D, and a blower 32 associated with the furnace 18A and air conditioner 18B, all of which are centrally controlled by a single integrated Device 12 controls.

Based on the comparison of the actual indoor temperature (T _I ) sensed by the indoor temperature sensor 20 and the actual outdoor temperature (T _O ) sensed by the outdoor temperature sensor 24, the single integrated centralized control device 12 operates in heating mode or cooling mode . The user enters the user's desired indoor temperature level 26, the user's desired indoor relative heating humidity level 28A, and the user's desired indoor relative cooling humidity level 28B. When the actual indoor temperature (T _I ) is lower than the actual outdoor temperature (T _O ), the single integrated centralized control device 12 will work in the heating mode. Conversely, when the actual indoor temperature (T _I ) is greater than the actual outdoor temperature (T _O ), the single integrated centralized control device 12 will work in the cooling mode.

In heating mode (also referred to as active humidification mode), a single integrated centralized control device 12 can be used to regulate the furnace 18A including the associated blower 32 as needed to achieve the user's desired indoor heating temperature level. Humidifier 18C and ventilator 18D are also adjusted as needed to achieve user desired heated indoor relative humidity level 28B and user desired indoor fresh air level 30 .

The single integrated centralized control device 12 receives input from the actual indoor temperature sensor 20, the actual indoor relative humidity sensor 22, and the user. The user inputs include a user desired room heating temperature level, a user desired room heating relative humidity level 28A, and a user desired room fresh air level 30 . The single integrated centralized control device 12 compares the actual indoor relative humidity (H _I ) with the user's desired indoor heating humidity level 28A. If the actual indoor relative humidity (H _I ) is lower than the user's desired indoor relative heating humidity level 28A (this situation usually occurs during the heating season), the single integrated centralized control device 12 selectively activates the humidifier 18C to bring the actual indoor The relative humidity (H _I ) increases to a value close to the user's desired indoor relative heating humidity level 28A. If the actual indoor relative humidity (H _I ) exceeds the user's desired indoor relative heating humidity level 28A, the single integrated centralized control device 12 selectively activates the ventilator 18D to bring cool, dry, fresh outdoor air into the building structure, effectively Reduce the actual indoor relative humidity (H _I ) to a value close to the user's desired indoor relative heating humidity level 28A.

Figure 4 shows a graph of active humidification in heating mode.

In the cooling mode (also known as the active dehumidification mode), when it is necessary to achieve the user's desired indoor cooling temperature level, the user's desired indoor cooling humidity level 28B, and the user's desired indoor fresh air level 30, a single integrated centralized control Device 12 may be used to condition air conditioner 18B, humidifier 18C, and ventilator 18C including associated blower 32 .

The single integrated centralized control device 12 receives input from the actual indoor temperature sensor 20, the actual indoor relative humidity sensor 22, and the user. The user inputs include the user desired room cooling temperature, the user desired room cooling humidity level 28B, and the user desired room fresh air level. The single integrated centralized control device 12 compares the actual indoor relative humidity (H _I ) with the user's desired indoor cooling humidity level 28B. The actual indoor relative humidity (H _I ) may exceed the user's desired indoor relative cooling humidity level 28B; this usually occurs during the cooling season. The single integrated centralized control device 12 then selectively adjusts the temperature of the output air generated by the air conditioner 18B below the user's desired room cooling temperature and reduces the airflow generated by the associated blower. This will reduce the actual indoor relative humidity (H _I ) to a value close to the user desired indoor relative cooling humidity level 28B. If the actual indoor relative humidity (H _I ) is lower than the user's desired indoor relative cooling humidity level 28B, the single integrated centralized control device 12 selectively activates the ventilator 18D to bring warm, moist, fresh outdoor air into the building structure. This effectively increases the actual indoor relative humidity (H _I ) to a value close to the user's desired indoor relative cooling humidity level 28B.

In addition, when operating in cooling mode, the single integrated centralized control device 12 can be used to adjust the airflow of the blower 32 to balance cooling (sensitive heat) demand and dehumidification (latent heat) demand. When there is a high demand for sensible heat (the user's desired indoor temperature is difficult to maintain) but there is no latent heat demand (the actual indoor relative humidity is lower than the user's desired indoor relative humidity), the single integrated centralized control device 12 adjusts the air blower 32 to increase the required temperature. The sensible heat ratio of the delivered air conditioning capacity. Conversely, when there is little cooling demand (the actual room temperature is at or slightly below the user's desired room temperature) but the actual room relative humidity is higher than the user's desired room relative humidity, adjust the blower to reduce the sensible heat ratio .

Figure 5 shows a graph of active dehumidification in cooling mode.

Therefore, when the single integrated centralized control device 12 is working in the heating mode, all environmental controls are calculated based on the user's desired indoor heating temperature and the user's desired indoor relative heating humidity level 28A. On the contrary, when the single integrated centralized control device 12 is working in the cooling mode, all environmental controls are calculated based on the user's desired indoor cooling temperature and the user's desired indoor relative cooling humidity level 28B. Likewise, a single integrated centralized control device 12 can be used to control all devices 18 required to achieve the user's desired indoor environmental conditions during the heating season and the cooling season.

FIG. 3 illustrates an example screen of the user interface 16 in which a user enters a user desired relative humidity input 28 . The user enters the desired heating indoor relative humidity level 28A and the desired cooling indoor relative humidity level 28B into the user interface 16 (FIG. 2). The user interface 16 then transmits the user input to the single integrated centralized control device 12 . Of course, this is just one example screen of the user interface 16 . Different screens are available for the user to enter other types of inputs such as user desired room heating temperature level, user desired room cooling temperature level and user desired fresh air level.

Also included are protection components to avoid condensation on building interior surfaces (customer option). This feature is in commonly assigned, co-pending U.S. Patent Application Serial No. 11/016,373, entitled "Determination of Maximum Allowable Humidity in Indoor Space to Avoid Condensation Inside Building Envelope," filed December 17, 2004 published in , the disclosure of which is hereby incorporated by reference in its entirety. In this option, a single integrated centralized control device 12 calculates the maximum allowable indoor relative humidity based on indoor and outdoor characteristics to prevent condensation, and adjusts the actual indoor relative humidity to prevent condensation.

In this embodiment, the single integrated centralized control device 12 converts the information entered into the user interface 16 by the owner or system installer into an adjustment factor A ^* using a conversion table (CT) as illustrated in FIG. 6 . After conversion, the single integrated centralized control device 12 then calculates the effective ΔT based on the following formula:

ΔT=A*(t ₂ -t ₁ )

After calculating the effective ΔT, the single integrated centralized control device 12 uses the allowable humidity table (AHT) as illustrated in FIG. 7 to determine the maximum allowable indoor relative humidity. Of course, other methods of comparing such tables to determine reference values are within the scope of the present invention. Any method that utilizes user input and environmental input to determine a reference value for comparison to a table is within the scope of the present invention.

After determining the maximum allowable indoor relative humidity, the single integrated centralized control device 12 can be used to selectively activate/deactivate indoor devices to adjust the actual indoor relative humidity to a value less than the calculated maximum allowable indoor relative humidity to prevent condensation.

When this option is activated, the single integrated centralized control unit 12 increases the intake of fresh air from the ventilator to reduce the Actual indoor relative humidity. A single integrated centralized control device 12 can be used to bring in fresh air to achieve the user's desired fresh air level, but limit or stop air intake for extreme (very hot or very cold) outdoor environmental conditions, so as to minimize the impact on indoor environmental conditions . Figure 8 shows a graph of the fresh air control portion of a single integrated centralized control device 12 utilizing a humidifier 18C and a ventilator 18D.

Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.

Claims (21)

1. single integrated control device that is used for the HVAC system comprises:

Central control device, wherein said central control device can be used to control the indoor relative humidity and the actual indoor fresh air level of indoor temperature actual between heating season and cooling seasonal period, reality.

2. single integrated control device as claimed in claim 1, also comprise indoor temperature transmitter, indoor relative humidity sensor and outdoor temperature sensor, wherein said central control device can be used to receive the input from described indoor temperature transmitter, described indoor relative humidity sensor and described outdoor temperature sensor.

3. single integrated control device as claimed in claim 2, the user interface that also comprises user-operable, be used for importing the indoor temperature of at least one user's expectation, the indoor fresh air level of the indoor relative humidity of at least one user's expectation and user's expectation, wherein said central control device generates signal to control the indoor temperature of described reality based on described input, the indoor fresh air level of the indoor relative humidity of described reality and described reality, thus reach the indoor temperature that described at least one user expects, the indoor fresh air level of the indoor relative humidity of described at least one user's expectation and described user expectation.

4. single integrated control device as claimed in claim 3, wherein said central control device is worked under heating mode and cooling pattern.

5. single integrated control device as claimed in claim 4, wherein: when described central control device is worked under described heating mode, the indoor temperature of described at least one user's expectation comprises the indoor heating temperature that the user expects, and the indoor relative humidity of described at least one user's expectation comprises the indoor relative heating humidity that the user expects.

6. single integrated control device as claimed in claim 5, wherein: when the indoor relative humidity of described reality was higher than the indoor relative heating humidity of described user's expectation, the indoor fresh air level of described reality was increased.

7. single integrated control device as claimed in claim 5, wherein: when the indoor relative humidity of described reality was lower than the indoor relative heating humidity of described user's expectation, the indoor fresh air level of described reality was lowered.

8. single integrated control device as claimed in claim 4, wherein: under described cooling pattern, work at described central control device, the indoor temperature of described at least one user's expectation comprises the indoor cooling temperature that the user expects, and the indoor relative humidity of described at least one user's expectation comprises the indoor relative cooling humidity that the user expects.

9. single integrated control device as claimed in claim 8, wherein: when the indoor relative humidity of described reality was lower than the indoor relative cooling humidity of described user's expectation, the indoor relative humidity of described reality was increased.

10. single integrated control device as claimed in claim 8, wherein: when the indoor relative humidity of described reality was higher than described cooling indoor relative humidity, the indoor relative humidity of described reality was lowered.

11. single integrated control device as claimed in claim 3, wherein: described central control device is controlled the indoor relative humidity of the indoor temperature of described reality, described reality and the indoor fresh air level of described reality by at least one device that optionally starts and stop the HVAC system.

12. single integrated control device as claimed in claim 2, also comprise: be used to import the user interface of user's input and wherein said central control device and receive at least one environment input from sensor, calculate effective Δ value based on described user's input and described at least one environment input, determine that based on described effective Δ value maximum allows indoor relative humidity, and the indoor relative humidity of regulating described reality is to the value of allowing indoor relative humidity less than described maximum.

13. single integrated control device as claimed in claim 12, wherein said user imports and represents the building structure feature.

14. single integrated control device as claimed in claim 12, wherein said user's input is at user option humidity.

15. a HVAC system comprises:

Single integrated central control device;

Temperature control equipment;

Humidity conditioner;

Fan unit; And

Ventilating device, wherein: described single integrated central control device can be used to control described temperature control equipment, described humidity conditioner, described fan unit and described ventilating device to reach the value of setting of user's expectation season at heating season and cooling.

16. HVAC as claimed in claim 15 system, wherein said pressure fan is optionally started and is stopped with the control sensible ratio.

17. a method of controlling the HVAC system comprises:

The indoor environment feature of at least one user's expectation is input into single integrated central control device;

Measure at least one actual environment feature;

Described at least one actual environment feature is transferred to described single integrated central control device; And

Based on the environmental characteristic of described at least one user expectation and described at least one actual environment feature, at least one actual indoor environment feature of centralized Control between heating season and cooling seasonal period.

18. method as claimed in claim 17 comprises the steps: that also indoor relative humidity in reality is higher than the occasion that desired indoor relative humidity and outdoor temperature are lower than predetermined temperature, increases actual indoor fresh air level.

19. method as claimed in claim 17 comprises the steps: that also indoor relative humidity in reality is lower than the occasion that desired indoor relative humidity and outdoor temperature are lower than predetermined temperature, reduces actual indoor fresh air level.

20. method as claimed in claim 17 comprises the following steps: that also indoor relative humidity in reality is lower than the occasion that desired indoor relative humidity and outdoor temperature surpass predetermined temperature, increases actual indoor fresh air level.

21. method as claimed in claim 17 comprises the following steps: that also indoor relative humidity in reality is higher than the occasion that desired indoor relative humidity and outdoor temperature surpass predetermined temperature, reduces actual indoor fresh air level.

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