US20250305704A1

US20250305704A1 - Control and fault detection of kitchen exhaust and makeup air systems

Info

Publication number: US20250305704A1
Application number: US19/094,972
Authority: US
Inventors: Vishal Patwari
Original assignee: Budderfly Inc
Current assignee: Budderfly Inc
Priority date: 2024-03-29
Filing date: 2025-03-30
Publication date: 2025-10-02

Abstract

A system and method of measuring, monitoring and adjusting fan controls in make up air units and restaurant kitchen hood appliances to provide a balanced air environment in an energy efficient manner including by monitoring the presence of exhaust gasses, flow rates of exhaust and makeup air along with pressure and temperature of the various spaces in a space such as a restaurant space including a kitchen.

Description

FIELD OF THE INVENTION

The present invention relates to systems and methods that identify air pressure imbalances and other system faults through real time monitoring of kitchen hood and make-up air systems in restaurant kitchen environments.

BACKGROUND OF THE INVENTION

It is important to keep a pressure balance in an enclosed building between incoming airflow and outgoing air. Not only can an out of balance system cause issues such as doors being hard to open on negative balance, or forced open on positive balance, an out of balance system can drastically affect energy costs for a facility.
A restaurant kitchen environment is particular in that there are high powered kitchen hoods and vents that expel cooking fumes. There may be one or more of these.
There are inherent inefficiencies in kitchen hood operation in the restaurant environment. These systems may be set to run all the time pulling out conditioned air from the space or may have maintenance issues leading to suboptimal performance.
In many cases these hoods are left on unnecessarily. Cooks or personnel turn on the hood fan in the morning, or when they start cooking and turn it off at the end of the day. In some cases, they even forget to turn off the hood or leave it on purposefully to clear out any remaining cooking fumes or smells. Some restaurants operate 24/7 and these fans may be on all the time.
In other cases, lack of maintenance of these kitchen hoods can lead to clogged filters that hamper the ability to adequately exhaust fumes at times when the fumes are most prevalent. This can lead to the fumes not being properly exhausted in an expeditious manner and the cook leaving the fan on longer than required to expel the fumes if the unit was working as designed. Vents can also clog up or outside ductwork may have items placed in front of it or be damaged or soiled affecting the unit's performance.
Additional faults can occur in the heating or cooling systems built into make-up air systems where these fail, air at outside temperatures is brought into the room without appropriate conditioning leading to high HVAC usage to compensate for the temperature differential.
In other installations, the balance between the makeup air supply and the kitchen hood is not properly configured. This can be a commissioning fault or can also get affected by inefficiencies such as clogged filters, improper installation, or equipment failure. If the vent fan is not expelling as much air as expected, the make-up air can be bringing in more air than needed leading to a positive pressure balance. In such cases, doors may pop open in the restaurant or windows may be difficult to open. The system also conditioned more air than required and introduces this to the space.
In other cases, the makeup air may be inadequately configured or improperly designed leading to insufficient, or excess make up air for the facility. As more air is exhausted than introduced, a negative balance occurs in the room making doors sticky and difficult to open and windows again difficult to open due to the pressure balance. As less air is exhausted than introduced, a positive overbalance occurs in the room making doors sticky and difficult to walk out of the building due to the pressure balance.
Again, units work harder, replacing more conditioned air and driving powerful fans consuming energy.
Frequent opening of doors, windows or the use of a drive-up window also affects room pressure balance throwing system out of balance.
Most users of the system are unaware of how much energy replacing the exhaust air takes, and simply don't think about the economics of turning the fan on or off. Kitchen hood fans remove not only the cooking fumes but also the conditioned air in the space where they operate. A commercial kitchen hood typically operates at about 1,000 CFM, larger kitchens may employ as much as 4,000 CFM or more. If you consider a kitchen area of 10×10 with a 10 ft ceiling one has 1000 cubic feet of volume, and this air can be exchanged every minute essentially expelling the air in the room that the HVAC system has worked hard to warm or cool to the desired setting.
With a large temperature differential of inside temperature and outside temperature, such as a hot summer or a cold winter, significant additional energy can be needed to condition the space. While the walls and items in the room also retain some of the heat and aid in maintaining the temperature, the costs of conditioning this replacement air for the room that is quickly expelled by the exhaust add up quickly.
Despite this, the typically cook or restaurant employee does not put much emphasis on energy savings when it comes to kitchen venting fans and may see these simply as a function to rid the restaurant of cooking fumes. Further, the installers or designers of the system may not have designed or installed the system properly to have a good balance of input air and exhaust air in the first place. Finally, systems over time require maintenance and may have faults which are not apparent or detected leading to what can become a drastic increase in energy costs to a facility.
To address some of the above-listed problems, various systems have been proposed with limited success.
European patent EP2292981B1 to Thompsom et. al. titled Variable Ventilation method and system describes relates to a variable ventilation system for a kitchen wherein exhaust rates are determined based upon the current operation of one or more kitchen appliances.
U.S. Pat. No. 5,139,009 to Walsh describes an exhaust ventilation control system for use with a ventilation system located at a cooking station and having one or more exhaust fans for exhausting air containing cooking by-products from the cooking station to an external environment, can alter operation of the exhaust fans to match the exhaust requirements to the cooking load. The exhaust ventilation control system includes an exhaust control connected to the exhaust fans for controlling operation of the exhaust fans in response to operation of the cooking areas.
These systems do not account for the temperature of the incoming air, or other outside factors that may offset efficiencies of the system. The disclosed system also fails to detect or alert if faults or maintenance is required within the makeup air or the kitchen hood.
Therefore, a need exists for an energy efficient system to monitor the balance of the input and output air pressure in a restaurant kitchen environment in a near real time fashion including the temperature of the input air and the CFM (cubic feet per minute) performance of the fans compared to an expected baseline to provide optimal energy efficiency.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a system and method of detecting faults in a kitchen hood and makeup air system deployed in a restaurant kitchen. In essence, the continual monitoring of the airflow, the input air temperature, and the room pressure through the use of sensors, a central monitoring and control system and local controllers and data gatherers on the kitchen hood and the makeup air system are used.
It is an object of the present invention to provide a method of verifying that an installed system is in balance, and then through continuous monitoring in near-real time detecting if the system in out of balance compensating for influences from outside factors like open windows or doors.
It is an additional object of the present invention to notify and alert personnel of situations where the system is out of balance or if components of the system such as heating or cooling systems in the makeup air have failed, if filters have become clogged, or if there are problems in airflow due to fan or fan motor issues, blocked vents, or if for whatever reason balance cannot be achieved.
Accordingly, it is desired to provide a system and method that can monitor the input and output air of a kitchen environment, for example in a quick serve restaurant (QSR) kitchen. The system and method provides for measurement of the air volume in CFM of both the makeup air and the kitchen hood exhaust air whereby air is replaced at a rate commensurate with the volume of cooking fumes and make up air is brought in to the space at a proportional rate. Further, the pressure in the room is measured allowing the detection of overly positive or negative pressure, and the temperature of the incoming air is measured to detect faults in the makeup air conditioning unit.
A system that automates fault detection of the kitchen hood and related make-up air unit is proposed, that can detect maintenance issues such as clogged filters, imbalance issues such as faulty installation or design, as well as fault detection such as failed components including fans, ductwork, or heating and cooling systems. A system of alerting is provided to notify of the faults and extrapolate potential problems to aid in diagnosis and repair.
A continuous monitoring system and method that measure airflow of the kitchen hood controlling the makeup air allowing these to work in tandem with appropriate speeds is done through a set of sensors including pressure sensors, temperature sensors and air volume flow sensors which sensor data is fed to a controller which regulates the control/speed of the various fans of the makeup air system and also allows for fault detection or maintenance needs.
Further, when errors are detected, alerts are generated with information about the potential fault and probable cause.
In one configuration, air flow is measured of both the exhaust system and makeup air system, and a comparison of the two airflows is correlated with the pressure balance in the room.
In another configuration temperature sensors are used to measure input air temperature into the room for the makeup air allowing for the detection and diagnosis of faults in the heating or cooling system of the makeup air unit.
In another configuration sensors for pressure in the room are used to detect potential issues in either unit or in design or configuration of the system indicative of the system not being in proper balance.
Additional pressure sensors can optionally be deployed to also offset the effect of open windows or windows that can adjust the room pressure. Typically, a momentary opening of a door does not have a major impact but in some locations where, for example a drive through window may be present and open for long periods of time pressure balance is affected. That said, it is not ideal to have the non-conditioned air being brought into the premises to compensate for pressure generated by the kitchen hood, thus the placement of the make-up air and the use of makeup air bringing in conditioned air is still preferred.
It is further contemplated that sensors to detect cooking activity including air temperature near the vent through a temperature sensor and cooking oil vapor sensors are used and these provide input signals to the central controller that in turn can detect if the kitchen hood vent fan operation is configured correctly.
A fudge factor can be factored into the airflow to reduce pre-heating and cooling and thus saving energy costs when temperature differentials with outside air are high. A slight off-balance in pressure in order to save energy is tolerable and thresholds are utilized in the system to compensate for this before alerts are generated.
It is further contemplated that if potential faults are detected in the system, further diagnosis may be configurable including restarting components of the system or running diagnostics where appropriate.
These and other objects and aspects are achieved by providing a system for balancing exhaust venting and makeup air in a space. The system includes a plurality of sensors in communication with a system computer having software executing thereon. A first one of the sensors is an exhaust detector configured to measure presence of exhaust from cooking. A second one of the sensors is a pressure sensor configured to measure air pressure in the space. The computer is in communication with an exhaust system which includes a variable speed fan whose speed is configured to be controlled by the computer. A third one of the plurality of sensors is an exhaust flow sensor configured to provide a measurement indicative of a rate at which the exhaust is expelled by the exhaust system. The is further in communication with a makeup air system which is configured to deliver air to the space and said computer further configured to provide control instructions to the makeup air system to vary a rate with which makeup air is provided to the space and to vary a temperature of the makeup air. The software receives data from each of the first, second and third ones of the plurality of sensors and based on said data the software determines a speed for the variable speed fan of the exhaust system and the rate which the makeup air is provided to the space. The software varies the speed for the variable fan and the rate in order to maintain pressure readings from the second one of the plurality of sensors within a range. The speed of the of the variable speed fan is varied based on the first and third ones of the plurality of sensors in order to control temperature within a temperature range and to control the exhaust within an exhaust range.
In certain aspects the software is configured to receive data from a fourth sensor, the data from the fourth sensor is data indicative of temperature associated with the space and based on the data from the fourth sensor, the software generates control instructions for the group consisting of: the variable speed fan, the makeup air system and combinations thereof. In other aspects, the plurality of sensors comprises a fifth sensor which is configured to provide the software with data indicative of a state of one or more cooking appliances associated with the exhaust system and the software configured to activate the variable speed fan based on the data indicative of the state of one or more cooking appliances.
In other aspects, based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system.
In yet other aspects the software is further in communication with and a room conditioning unit configured to deliver conditioned air to the space and the software is further configured to control a rate and/or temperature of conditioned air delivered to the space by the room conditioning unit and the makeup air unit along with the speed of the variable speed fan based on the measured air pressure.
In still other aspects the space includes a kitchen area and a second area and the makeup air system is located in the kitchen area. In other aspects the makeup air system is located adjacent to the exhaust system.
Other objects and aspects of the invention are achieved by providing a system for balancing exhaust and makeup air in a restaurant space which includes a kitchen space. The system includes software executing on a computer which software is in communication with a plurality of sensors, an exhaust vent, a makeup air system and a room conditioning unit. The makeup air system is located in the kitchen space and the room conditioning unit is configured to deliver conditioned air to the restaurant space. The software is configured to receive data from said plurality of sensors which data includes:—data indicative of exhaust amount or presence from an exhaust detector;—data indicative of a pressure in the restaurant space from a pressure sensor;—data indicative of exhaust flow rate from an exhaust flow sensor associated with an exhaust system;—data indicative of a state of a cooking appliance associated with the exhaust system from a state sensor; and—data indicative of a temperature associated with the restaurant space from a temperature sensor. The software analyzes the received data and transmits instrucitons to control:—a speed of a variable fan associated with the exhaust system based on data from two or more of the exhaust detector, exhaust flow sensor, temperature sensor and state sensor;—a first rate and first temperature of air delivered to the kitchen space via the makeup air system based on data from at least one of the temperature sensor, exhaust flow sensor and the exhaust detector; and—a second rate and second temperature associated with the room conditioning unit for conditioning the restaurant space while maintaining pressure in the restaurant space within a range based on the data from the pressure sensor.
In certain aspects the makeup air system is located adjacent to the exhaust system. In other aspects the software is further configured to control a rate and/or temperature of conditioned air delivered to the space by the room conditioning unit and the makeup air unit along with the speed of the variable speed fan based on the measured air pressure. In still other aspects based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system. In still other aspects the software generates an alert when a fault has occurred with the exhaust system. In yet further aspects the software is configured to activate the variable speed fan based on the data indicative of the state of one or more cooking appliances. In still other aspects the exhaust detector is located in or adjacent to a vent hood and the pressure sensor includes a plurality of pressure sensors positioned spaced from each other within the restaurant space, at least one of the pressure sensors is located in the kitchen space. In still other aspects the makeup unit comprises makeup air sensors including a temperature sensor and a flow rate sensor and the software is configured to receive temperature and flow rate data from the makeup air sensors and the software further configured to control a variable speed fan and a heating and/or cooling unit of the makeup air system based on the temperature and flow rate data from the makeup air sensors.
Other objects and aspects of the invention are achieved by providing a method of balancing exhaust and makeup air in a kitchen space including one or more of the steps of: providing software executing on a computer; receiving at said software data from a plurality of sensors; receiving data at the software from a first one of the plurality of sensors is an exhaust detector which is configured to provide data to the software indicative of presence of exhaust from cooking in the kitchen space; receiving data at the software from a second one of the plurality of sensors which is a pressure sensor configured to provide data to the software indicative of an air pressure in the space; receiving data at the software from a third one of the plurality of sensors which is an exhaust flow sensor configured to provide a measurement indicative of a rate at which the exhaust is expelled by an exhaust system; receiving data at the software from at least a fourth one of the plurality of sensors which includes one or more temperature sensors associated with the space; and controlling via aid software, the exhaust system and a makeup air system, said software generating control instructions to control a speed of a variable fan associated with the exhaust system based on the data from the first one of the plurality of sensors and said software generating instructions to control a rate at which makeup air is delivered to the space based on the data from the second and third ones of the plurality of sensors such that pressure of the space remains within a predetermined range, and that the software controls exhaust in the space to remain within below a predetermined amount while the rate at which makeup air is delivered to the space is controlled based on readings from the third one of the plurality of sensors and said software further configured to control a temperature of air delivered by the makeup air unit to the space based on readings from the at least a fourth of the plurality of sensors.
In certain aspects the makeup air system is located adjacent to the exhaust system. In other aspects based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system. In yet other aspects, the software activates the variable speed fan based on the data indicative of the state of one or more cooking appliances. In still other aspects, the exhaust detector is located in or adjacent to a vent hood and the pressure sensor includes a plurality of pressure sensors positioned spaced from each other within the restaurant space, at least one of the pressure sensors is located in the kitchen space.
Other objects of the invention and its features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts the components of a continual monitoring kitchen ventilation system in a kitchen.

FIG. 2 is a functional flow diagram of some of the components of FIG. 1 .

FIG. 3 is a functional flow diagram showing reporting functions and fault detection of the system of FIG. 1 .

FIG. 4 is a logic flow diagram according to an aspect of FIG. 1 .

FIG. 5 is a birdseye view diagram of additional features of the system of FIG. 1 .

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.
FIG. 1 is a depiction of the components used in the continual commissioning kitchen ventilation system.
Kitchen hood 10 is depicted with embedded sensors 20 for air speed and temperature as well as particulate detection to determine if fans are running at an appropriate rate, these may include separate exhaust flow, temperature and exhaust detector sensors or the same combined into one unit. Fan 15 and controller 25 receive sensor data from these sensors either via an internet/cloud connection or optionally a direct electrical connection. The kitchen hood 10 picks up hot air 30 from a cooking area 35 which can be a stove, cook top, fryer or a combination thereof.
The hot air 30 is sucked through the kitchen hood 10 with the fan 15 and expelled through a duct 65 to a vent 70 typically outside of the facility.
A makeup air system 40 with an embedded controller 55 fan 45 and sensors 50 is also used to match the escaping hot air 30 with makeup air 60. The sensors 50 include air flow rate and temperature sensors which allow the controllers 55 and 80 to trigger pre-cooling and pre-heating 52 of the makeup air 60 into the facility. In many cases a slight temperature imbalance is not sufficient to trigger this mechanism, but it is there to prevent large differences in temperature from occurring. The sensors 50 can also be used to detect failures when airflow is insufficient such as potential fan or fan motor failure or ventilation blockage or partial blockage. Sensors 50 for temperature can also be used to detect failures in the pre-heat/pre-cooling 52 system with alerts being generated based on the sensor data by the central controller 80 (or generated by local controllers and sent to the central controller). A makeup air system is provided at or adjacent to the hood and is able to provide more rapid response to heating or cooling needs based on variations of the exhaust rate than a traditional HVAC unit designed to condition the overall space.
The local controllers on the kitchen hood 25 and make up air system 55 and their various components including sensors and controllable components (fans heating/cooling) are connected over the cloud to a central controller 80 which is running control and monitoring software 85. The controller may include a processor with software executing thereon. The controller may further be an analog controller which can receive inputs from the central controller 80 or local controller 110 (FIG. 5 ). Room sensors are also connected to the central controller. There may additionally be a local controller as shown in FIG. 5 to which the various devices in the space are connected which in turn the local controller is connected to the central controller. The devices may also be connected through physical wires in another configuration but since the central controller can manage multiple sites the connections are typically over the cloud/network connections. The central controller software 85 can also be installed directly in the cloud but are depicted as a dedicated box in the diagrams herein. These systems, while labeled controllers and capable of control of the various components are used in the context of data gathering in the proposed system.
Turning now to FIG. 2 , we see the same central controller 80 and controller software 85 connected to the cloud to a single site where one or more kitchen hood systems 25 and one or more make up air systems 40 are deployed.
FIG. 3 depicts the same central controller 80 and controller software 85 connected to multiple sites 300 where each site can be make-up of or more kitchen heads and make up air units such as depicted in FIG. 2 and FIG. 1 .
Additionally, the central controller and central controller software generates email alerts and alarms 320 as well as providing statistics and reporting capabilities 340. Further, the firmware and software in the local controllers and central controller may require occasional updating or may support diagnostic and control functions that can aid in fault determination. These updates and functions 330 are also provided through the cloud.
Further, temperature sensors in the hood allow for turning the fan on and off. Temperature sensors for air exchangers are also used to turn on or off the heating and cooling systems to precondition the air that is entering the facility.
Turning now to FIG. 4 we see the logic behind the fan control to achieve the continuous commissioning system.
The system starts 400 operation and checks for whether cooking is detected 405. This can be done through manual controls triggered by the cook, through detecting hood temperature or cooking fumes.
If there is no cooking detected the fan should be turned off and the system continues to monitor the cooking operation 405. If the fan remains off for a long period of time the system may detect this 406 with a timer and generate an alert 490.
If cooking is detected the kitchen hood 405, the system will monitor the CFM on the fan to see if there is air movement 410. If not, a possible fan failure or power issue 450 may be present. Next the system will compare the CFM rate to acceptable levels 425 and if this is not the case a blocked filter or failing fan 455 may be suspected.
CFM rates are measured 420 and compared with input make-up air and exhaust fan air and if these rates are not within expected thresholds a miscalibration or faulty installation 460 may be detected.
The air movement from the makeup air is measured and if there is no air movement or insufficient CFM 425 then a possible failed fan or power issue or blocked air entry 465 may be suspected.
The makeup air rate is measured 430 and compared with kitchen vent air and if these rates are not within expected thresholds a miscalibration or faulty installation 470 may be detected.
The temperature of the makeup air is measured 435 and if not within expected thresholds a failed heating or cooling unit or thermostat or power issue 475 may be detected.
Finally room pressure is measured 440 and compared to acceptable bounds and if not acceptable a miscalibration or faulty installation 470 may be detected.
In each failure case, the system generated an alarm 490 which may lead the central system to run diagnostics 491 which if not resolved 494 may generate an alert with context information 495 that triggers a site visit.
After any alarm is generated 495 or if the pressure is acceptable 440 after all the tests, the system resumes monitoring 405 in a continuous fashion.
Referring to FIG. 5 a birdseye view of an example restaurant and kitchen space is shown. The kitchen space 108 may be separate from the eating space 112 via a door or the kitchen area 108 may be open to the eating space 112 which includes tables 100. The cooking appliance 35 (in this case a range) includes a hood 25, both with the elements depicted in FIG. 1 . The cooktop may have a state sensor 107 which provides the controller (110 and/or 80) with state data indicative of if the cooking appliance (cooktop in this case) is on and to what degree the cooktop is on. Such data may include power level, and how many burners are active (and the power level for each one). This information may in turn be used by the controller(s) 110/80 to provide instructions to the variable speed fan of the hood 25. The hood 25 may further include exhaust detectors as part of the hood sensors 20 which identify particulates/gasses associated with cooking which should be removed. Additional temperature sensors 106 may be located throughout the space 300 and the hood 25 may further include a temperature sensor as well. The temperature, exhaust detector and state sensor 107 may be used to enable to controller 110/80 to determine how to set the variable fan 15 of the exhaust vent hood. The hood sensors 20 may further include exhaust rate sensors 109 which measure the volume/flow rate of gasses out the exhaust hood. A comparison of the actual flow to the expected flow given the fan 15 speed can help to identify faults and is further used by the controller 110/80 to determine a setting for the makeup air 40 system. The makeup air system incudes a variable fan 45, sensors 50 and a pre heater/cooler to heat/cool the air which is provided to replace the exhausted air. The makeup air system as shown in FIGS. 1 and 5 is within the kitchen area 108, and particularly positioned adjacent to the vent hood. This allows the makeup air system to be built to easily and quickly respond to changes in need of volume and temperature of makeup air which HVAC system for the overall space 300 may not be as capable of dealing with. The makeup air sensors 50 include temperature and volume and then various room sensors such as temperature 106 and pressure 104 may be further connected to the controller 110/80 to enable balancing. Also connected to the controller is the HVAC 114 unit (heater, air conditioner etc). It is understood that the heating device may be a separate unit from the air conditioning device and that the HVAC 114 may represent one or multiple devices. With the controller 110/80 able to receive data from all the sensors as described herein, imbalances in pressure and temperature as determined by the various sensors may be accounted for by varying the speed/temperature/output of the exhaust vent and the makeup air system 40 and HVAC unit(s) 114. Furthermore the door 102 may include a sensor to indicate the extent to which the door is open and/or if the door is opened/closed. The door 102 may further include an air curtain whose speed can impact the pressure and the amount of makeup air needed, thus the air curtain of the door 102. It is understood that all the sensors described herein may be connected to the local controller 110 and/or central controller by wired or wireless connection or network connection and combinations thereof.
Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art.

Claims

What is claimed is:

1. A system for balancing exhaust venting and makeup air in a space comprising:

a plurality of sensors in communication with a system computer having software executing thereon;

a first one of the plurality of sensors is an exhaust detector configured to measure presence of exhaust from cooking;

a second one of the plurality of sensors is a pressure sensor configured to measure air pressure in the space;

said computer is in communication with an exhaust system which includes a variable speed fan whose speed is configured to be controlled by the computer.

a third one of the plurality of sensors is an exhaust flow sensor configured to provide a measurement indicative of a rate at which the exhaust is expelled by the exhaust system.

said computer in communication with a makeup air system which is configured to deliver air to the space and said computer further configured to provide control instructions to the makeup air system to vary a rate with which makeup air is provided to the space and to vary a temperature of the makeup air;

said software receiving data from each of the first, second and third ones of the plurality of sensors and based on said data said software determining a speed for the variable speed fan of the exhaust system and the rate which the makeup air is provided to the space, wherein said software varies the speed for the variable fan and the rate in order to maintain pressure readings from the second one of the plurality of sensors within a range and wherein the speed of the of the variable speed fan is varied based on the first and third ones of the plurality of sensors in order to control temperature within a temperature range and to control the exhaust within an exhaust range.

2. The system of claim 1 wherein the software is configured to receive data from a fourth sensor, the data from the fourth sensor is data indicative of temperature associated with the space and based on the data from the fourth sensor, the software generates control instructions for the group consisting of: the variable speed fan, the makeup air system and combinations thereof.

3. The system of claim 1 wherein the plurality of sensors comprises a fifth sensor which is configured to provide the software with data indicative of a state of one or more cooking appliances associated with the exhaust system and the software configured to activate the variable speed fan based on the data indicative of the state of one or more cooking appliances.

4. The system of claim 1 wherein based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system.

5. The system of claim 1 wherein the software is further in communication with and a room conditioning unit configured to deliver conditioned air to the space and the software is further configured to control:

a rate and/or temperature of conditioned air delivered to the space by the room conditioning unit and the makeup air unit along with the speed of the variable speed fan based on the measured air pressure.

6. The system of claim 1 wherein the space includes a kitchen area and a second area and the makeup air system is located in the kitchen area.

7. The system of claim 1 wherein the system further comprises a central computer with software executing thereon and the space comprises a plurality of spaces located geographically apart from each other in different buildings, said central computer in communication with the computer of each of the plurality of spaces via a network and the software of the central computer is configured to receive data from the plurality of sensors and is further configured to transmit control instructions to one or more of the computers to control the exhaust system and the makeup air system.

8. A system for balancing exhaust and makeup air in a restaurant space which includes a kitchen space comprising:

software executing on a computer, said software in communication with a plurality of sensors, an exhaust vent, a makeup air system and a room conditioning unit, wherein the makeup air system is located in the kitchen space and the room conditioning unit is configured to deliver conditioned air to the restaurant space;

said software configured to receive data from said plurality of sensors wherein said data includes:

data indicative of exhaust amount or presence from an exhaust detector;

data indicative of a pressure in the restaurant space from a pressure sensor;

data indicative of exhaust flow rate from an exhaust flow sensor associated with an exhaust system;

data indicative of a state of a cooking appliance associated with the exhaust system from a state sensor;

data indicative of a temperature associated with the restaurant space from a temperature sensor;

said software analyzing the received data and transmitting control instructions to control:

a speed of a variable fan associated with the exhaust system based on data from two or more of the exhaust detector, exhaust flow sensor, temperature sensor and state sensor;

a first rate and first temperature of air delivered to the kitchen space via the makeup air system based on data from at least one of the temperature sensor, exhaust flow sensor and the exhaust detector; and

a second rate and second temperature associated with the room conditioning unit for conditioning the restaurant space while maintaining pressure in the restaurant space within a range based on the data from the pressure sensor.

9. The system of claim 6 wherein the makeup air system is located adjacent to the exhaust system.

10. The system of claim 6 wherein said software is further configured to control a rate and/or temperature of conditioned air delivered to the space by the room conditioning unit and the makeup air unit along with the speed of the variable speed fan based on the measured air pressure.

11. The system of claim 6 wherein based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system.

12. The system of claim 11 wherein said software generates an alert when a fault has occurred with the exhaust system.

13. The system of claim 6 wherein the software is configured to activate the variable speed fan based on the data indicative of the state of one or more cooking appliances.

14. The system of claim 6 wherein the exhaust detector is located in or adjacent to a vent hood and the pressure sensor includes a plurality of pressure sensors positioned spaced from each other within the restaurant space, at least one of the pressure sensors is located in the kitchen space.

15. The system of claim 6 wherein the makeup unit comprises makeup air sensors including a temperature sensor and a flow rate sensor and the software is configured to receive temperature and flow rate data from the makeup air sensors and the software further configured to control a variable speed fan and a heating and/or cooling unit of the makeup air system based on the temperature and flow rate data from the makeup air sensors.

16. A method of balancing exhaust and makeup air in a kitchen space comprising:

providing software executing on a computer;

receiving at said software data from a plurality of sensors;

receiving data at the software from a first one of the plurality of sensors is an exhaust detector which is configured to provide data to the software indicative of presence of exhaust from cooking in the kitchen space;

receiving data at the software from a second one of the plurality of sensors which is a pressure sensor configured to provide data to the software indicative of an air pressure in the space;

receiving data at the software from a third one of the plurality of sensors which is an exhaust flow sensor configured to provide a measurement indicative of a rate at which the exhaust is expelled by an exhaust system;

receiving data at the software from at least a fourth one of the plurality of sensors which includes one or more temperature sensors associated with the space;

controlling via aid software, the exhaust system and a makeup air system, said software generating control instructions to control a speed of a variable fan associated with the exhaust system based on the data from the first one of the plurality of sensors and said software generating instructions to control a rate at which makeup air is delivered to the space based on the data from the second and third ones of the plurality of sensors such that pressure of the space remains within a predetermined range, and that the software controls exhaust in the space to remain within below a predetermined amount while the rate at which makeup air is delivered to the space is controlled based on readings from the third one of the plurality of sensors and said software further configured to control a temperature of air delivered by the makeup air unit to the space based on readings from the at least a fourth of the plurality of sensors.

17. The method of claim 16 wherein the makeup air system is located adjacent to the exhaust system.

18. The method of claim 16 wherein based on a comparison of information indicative of a speed of the variable speed fan to the rate at which exhaust is expelled by the exhaust system, the software determines if a fault has occurred with the exhaust system.

19. The method of claim 6 wherein the software activates the variable speed fan based on the data indicative of the state of one or more cooking appliances.

20. The method of claim 16 wherein the exhaust detector is located in or adjacent to a vent hood and the pressure sensor includes a plurality of pressure sensors positioned spaced from each other within the restaurant space, at least one of the pressure sensors is located in the kitchen space.