Patent Application
20110127343
The invention relates generally to heating systems and methods of controlling the same and, more particularly, to steam heat systems and controls and methods for controlling various aspects of the systems.
A conventional steam heating system includes a boiler and various radiators connected to the boiler by one or more pipes. There are different configurations such as a single pipe system with main pipes pitched towards the boiler, single pipe systems with main pipes pitches away from the boiler, stem trap systems, etc. Each of these configurations share some of the same elements. The boiler is typically located at the bottom of the system, such as in the basement of a building, and the radiators are typically located in various locations above the boiler, such as in various rooms of an apartment. When the system is operating correctly, water in the boiler is converted to steam, the steam rises through the pipes and into the radiators, the radiators heat up and the air in the rooms in which the radiators are located heat up. When the steam in a radiator cools, it condenses to water, which drains down the pipe(s) back to the boiler where it is again available to be converted into steam. This condensation makes more room for additional steam to be added to that particular radiator thus keeping the radiator hot. This condensation also creates a vacuum in the radiator which draws additional steam to replace the condensed steam. In an effort to prevent such a vacuum in the boiler, vacuum valves may be employed on or near the boiler. Additionally, to prevent an explosion due to pressure, safety valves may also be employed.
A conventional radiator, for ease of explanation, is essentially a conduit for the steam. At one end of the conduit is the pipe leading to the boiler. Radiators typically include a manual valve at this end of the radiator for connecting the radiator to and/or disconnecting the radiator from the system. At the other end of the conduit is a vent valve which allows cool air to be released from the radiator. When the system is operating and the vent valve is open, steam enters the radiator and pushes the cold air out through the vent valve. Once the steam reaches the vent valve, the valve closes, trapping the steam within the radiator. With the steam trapped in the radiator, the radiator heats up.
The vent valve is conventionally controlled by a bi-metallic strip or some other thermal or steam responsive strip that closes when it comes in contact with the steam. The size of the vent valve controls the rate at which a radiator is heated. A larger vent valve allows a radiator to heat quickly by quickly releasing the cool air from the radiator. A smaller vent valve forces a radiator to heat more slowly, by releasing the cooler air at a slower rate than the larger valve. Various vent sizes may be employed to meet different demands of various parts of a particular system.
While steam heat is relatively inexpensive and reliable it is not without its drawbacks. For instance, conventional steam heating systems do not discern which radiators to heat. Additionally, the heat is not evenly distributed throughout the system; i.e. those radiators closest to the boiler tend to receive more heat and receive the heat quicker than those farthest away. Further, steam heat tends to be inefficient to the extent that the boiler tends to operate at the same rate regardless of how many radiators actually need heat. These are some reasons steam heat is not typically utilized in residential houses. Instead, steam heat is typically reserved for large buildings.
Systems exist that attempt to regulate heating systems. Examples of such systems are U.S. Pat. No. 4,147,302 entitled Home Heating System Control, U.S. Pat. No. 6,454,179 entitled Method for Controlling a Heating System and a Heating System and U.S. Pat. No. 7,130,720 entitled Radio Frequency Control of Environmental Zones. However, these systems are either not related to steam heat, are not practical solutions and/or do not centralize the control of the system.
It would thus be advantageous to create steam heat systems and methods for controlling the same. It would also be advantageous to provide such systems and methods that are practical, require relatively low energy for control and which reduce energy requirements to operate the system.
Many advantages of the invention will be determined and are attained by the invention, which in a broadest sense provides steam heating systems and methods for controlling the same. In at least some embodiments it provides systems and methods for wirelessly controlling steam heat systems from one or more centralized locations. In at least some of the embodiments it provides latching solenoids for controlling one or more radiators. Implementations of the invention may provide one or more of the following features.
An aspect of the invention provides a system to facilitate the provision and regulation of steam heat in a building. The building may have multiple rooms, a boiler and multiple radiators. Each of the radiators is connected to the boiler via a network of pipes and there is a radiator located in many if not all of the rooms. They system includes a central processor that is configured to monitor and adjust the system. The central processor includes a central processor transceiver. The system also includes air vent controllers which include an air vent controller transceiver for wireless communication with the central processor. Each air vent controller is adapted to be attachable to a respective radiator. The air vent controllers may be selectively shifted from an open state to a closed state and visa versa. In the open state, an air vent controller allows air to flow through the air vent controller and in the closed state air is prevented from flowing through the air vent controller. The air vent controllers are separated into at least two groups. Each group will represent a heating zone in the building. The system also includes room thermometers respectively coupled at least to some of the air vent controllers. The room thermometers are configured to measure the room temperature in a room in which a radiator is located. The air vent controllers which are associated with a room thermometer are configured to communicate the room temperature and the state of the air vent controller to the central processor via the air vent controller transceiver. The central processor is configured to, at least in part in response to the communications from the air vent controllers, determine that a group of air vent controllers needs to be placed in the open state and to send an instruction to that group of air vent controllers to change to the open state. The group of air vent controllers for which the command is intended are configured to, in response to receipt of the instruction from said central processor, change to the open state.
Another aspect of the invention provides a method of providing steam heat to a building that has radiators connected to a boiler via a network of pipes. The method includes assigning identifiers to at least some of the radiators and separating the radiators into at least 2 groups using the identifiers to differentiate the groups. The method also includes configuring each of the radiators within a group to operate under a common set of parameters and monitoring the parameters at a central processor. The central processor receives communications from the radiators in the group and determines from those communications whether the group parameters indicate that the group requires heat. If the parameters indicate that the group requires heat, then the central processor determines the state of the boiler (whether the boiler is on or off). If the boiler is on then the central processor sends an instruction to the group of radiators to turn on. If the boiler is off then prior to sending the instruction to the radiators, the central processor sends an instruction to the boiler to turn on.
In another aspect of the invention a system is provided for facilitating a steam heating system. The system includes radiators, each having an inlet for steam and an outlet for air. At least some of the radiators are assigned an identifier (ID) for grouping multiple radiators together into multiple groups or zones. The system includes a source of steam (e.g. a boiler) and pipes/conduits connecting the steam source to the inlets of the radiators that have been assigned IDs. Steam from the source of steam is capable of traveling through the conduits to the inlet of each of the radiators pushing colder air through the inlet and out the outlet of each radiator until the outlets are closed. Once the outlets are closed, the steam is trapped in the radiator, the radiator heats up and heats the air in the room. Each of the radiators with an ID includes an air vent controller that is connected to the radiator at the outlet. The air vent controller automatically closes the outlet when a temperature of the radiator reaches a predetermined temperature thus preventing air to flow through said radiator. The system also includes a central processor located remote from the radiator, which is configured to wirelessly communicate with the air vent controllers in the groups of radiators. The central processor is also configured to signal the air vent controllers based on their groups to open the radiator outlets as a group based on predetermined parameters for the group. The air vent controller also includes a battery for providing pulses of electrical current to change the air vent controller from open to closed or closed to open and to provide electrical current for communicating with the central processor.
The invention will next be described in connection with certain illustrated embodiments and practices. However, it will be clear to those skilled in the art that various modifications, additions and subtractions can be made without departing from the spirit or scope of the claims.
For a better understanding of the invention, reference is made to the following description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which:
The invention will next be described in connection with certain illustrated embodiments and practices. However, it will be clear to those skilled in the art that various modifications, additions, and subtractions can be made without departing from the spirit or scope of the claims.
Referring to the drawings in detail wherein like reference numerals identify like elements throughout the various figures, there is illustrated in
In a preferred embodiment as illustrated in
Air vent control 70 may include a latching solenoid, a low voltage DC motor, a stepper motor, a servo motor or any other device, which can open and close the passage to air vent 60 without requiring constant application of electric current. The air vent control 70 is preferably powered by one or more batteries (not shown), but may alternatively or also be powered by solar panels (not shown) and/or thermoelectric cells (also not shown). While it is also within the scope of the invention that the air vent control 70 receives power by plugging into a standard electrical outlet, this is not preferred as radiators 30 are often not located proximate such an outlet. Air vent control 70 includes at least one radio frequency (RF) transceiver 50 for communicating with a central control 80. Those skilled in the art will recognize that the air vent control 70, and any other device that employs a transceiver, may include separate transmitter(s) and receiver(s) instead of, or in addition to, the transceiver 50 and still fall within the scope of the invention. Air vent control 70 may also include one or more thermometers for determining the temperature of the room and/or the outside air and/or the radiator 30. As illustrated in
Air vent control 70 also includes circuitry designed to be aware of the state of the passage to the air vent 60 (open or closed), to change the state of the passage, to receive input from the one or more thermometers, and to transmit any or all of this information to central control 80. Depending on the design choices made, the circuitry may also be required to convert some or all of the information from analog to digital and/or from digital to analog. The circuitry may include an application specific integrated circuit (ASIC), a reduced instruction set computer (RISC), a digital signal processor (DSP) or any other processing circuitry that can be configured to perform the above functions. Preferably, but not required, the circuitry will require relatively low power for operation.
System 10 also includes a central control 80. Central control 80 may be a computer running control software or it can be any other suitable processing device which can be used to schedule and or control the various air vent controls 70. Central control 80 also includes at least one RF transceiver 50 for communicating with air vent controls 70. Central control 80 may also be configured to communicate with and control boiler 20. Central control 80 may be hard wired to or may communicate wirelessly with boiler 20. If central control 80 communicates wirelessly with boiler 20 then boiler 20 will also require a transceiver 50 and a relay 55 for receiving and carrying out instruction from central control 80 to turn the boiler on/off. It will also need to be able to wirelessly transmit boiler status information (e.g. boiler pressure, and/or length of time boiler has been on, etc.) to central control 80.
When no heat is needed in any of the zones (440 of
Air vent control 70 and central control 80 may be designed to operate with existing systems and/or they could be designed to operate on newly installed systems. In this regard, a conventional radiator includes a threaded aperture designed to receive a threaded stem of an air vent 60. Thus, air vent control 70 may be designed with a threaded stem that is compatible with (capable of mating with) existing radiators. Additionally, air vent control 70 may be designed with a threaded aperture for receiving a conventional air vent 60. While not required, it is considered within the scope of the invention that vent control 70 may include an air vent 60 incorporated therein thus eliminating the need for a separate air vent. Alternatively, air vent control 70 may receive temperature readings from a thermometer 72 attached to the radiator 30 and automatically close when the radiator 30 reaches a predetermined temperature. If the entire system 10 is new, or if one or more radiators 60 are new, the air vent control 70 and the radiator 30 may be configured in any suitable fashion to be mated together or may be made as a single unit and still fall within the scope of the invention.
When the system 10 of
By way of a non-limiting example (illustrated in
At various offset intervals, to prevent interference between transmissions, the various air vent controls 70 communicate with central control to provide information such as the state of the air vent control 70 (open/closed) and the temperature in the room. Central control 80 then determines the average temperature for all rooms in a particular zone and determines whether or not the radiators 30 in that zone need to be turned on or off (440 of
Having thus described preferred embodiments of the invention, advantages can be appreciated. Variations from the described embodiments as illustrated in
An alternate embodiment is illustrated in
In
A room unit 200 can be designed to either communicate with a single air vent control via IR 1 and the central command via RF 2 communications or it can be designed to communicate with multiple or all air vent controls in a room if there are multiple radiators in a particular room. As with the above described embodiments, communications may be based on an ID of one or more units and/or a group/zone ID. Room units 200 do not need to be very complex. Their purpose is essentially to receive RF communications 2 and retransmit those received communications either in IR 1 if the communication is intended for an air vent control or in RF 2 if the communication is intended for the central control. Preferably, all IR communications 1 will be at a frequency that avoids interference from devices such as fluorescent lamps, etc.
When an air vent control communicates with central control it transmits an RF signal 2. This signal may be a burst communication or it may be a standard communication. While burst communications will save energy it is not a requirement. Since the RF communication 2 only needs to reach the room unit 200 the signal strength need not be very high. The room unit 200 detects the RF communication 2 and retransmits the communication to the central control 80 (with a stronger signal if necessary). The communication from the air vent control to the room unit 200 and the RF communications 2 between the room unit 200 and the central control 80 may be transmitted at the same frequency or they may be transmitted at different frequencies to avoid interference. Additionally, the RF frequencies can be designated particularly for a facility 500 and interference from other RF sources minimized with appropriate isolation techniques. A room unit 200 may be assigned its own ID for communications or it may share the same ID as the air vent controls with which it communicates.
In addition to the above features and functions, the invention may include additional energy saving features. For example, the system may include a pressure gauge on or near the boiler which can be employed to determine the minimum steam pressure of the boiler to reach a radiator and the minimum pressure required to reach all radiators so that they are all sufficiently heated for their settings. For example, all of the radiators can be turned off except one (e.g. the farthest from the boiler) and the boiler turned on. When that radiator reaches a sufficient temperature to heat the room to the desired temperature, the pressure at the boiler can be determined from the pressure gauge and stored for future use. Additionally, the amount of time it took for the radiator to reach the temperature can be stored and used for further refining the system. This process can be performed for individual radiators or groups of radiators. The system can then use this information to determine which boiler to employ (in a system with multiple boilers) and/or when the boiler can be turned off after supplying heat to a particular radiator or zone. The system may employ a thermometer in an outdoor location which communicates directly or indirectly with central control 80. Central control 80 can use this information to determine whether or not heat is required, regardless of whether or not the various zones are calling for heat. Various radiators may be flagged as being close to an exit door and thus receive special treatment. The furthest radiator from the boiler may be flagged for priority purposes, etc. Any or all of this information may be employed by central control to refine the system. The more information central control is provided the more robust the system can be and the more options it can have for programming. In addition to being placed on the radiators, air vent controls may be placed on various pipes throughout the system. This could be used to close off entire portions of the system thus enabling the steam to reach other sections of the system faster with less pressure required of the boiler.
An optional feature of the system is a choice between a more economical setting and a more luxurious setting. The more economical setting could require feedback from the radiators less frequently and/or it could react to temperature changes slower. For example, if the desired room temperature was 70 degrees, the more economical setting could wait until the temperature of the room reached 65 degrees before providing heat whereas under a luxury setting the system could be designed to provide heat if the temperature in the room dropped to 69 degrees. Those skilled in the art will recognize that this setting could be a sliding scale, a binary decision or fixed degrees such as 100% economy 50% economy 50% luxury and 100% luxury. 100% economy could be a 5 degree drop, 50% could be a 2 degree drop and 100% luxury could be a 1 degree drop. These are merely non-limiting examples.
When the system first turns on after being shut down for any substantial amount of time (e.g. the boiler and the various radiators are all cold) central control polls each air vent control 70 to determine the status of the radiator and room. It also determines the status of the boiler to make sure that it is cold and has been off for a sufficient amount of time that is determined to be safe. It may also determine the outside temperature. If the outside temperature is above the temperature set for heat then central control may leave the system off and wait for the outside temperature to drop before polling the air vent controls. Once the outside temperature drops, central control will begin polling (440 of
Thus it is seen that steam heat systems and methods for controlling various aspects of the systems are provided. Although particular embodiments have been disclosed herein in detail, this has been done for purposes of illustration only, and is not intended to be limiting with respect to the scope of the claims, which follow. In particular, it is contemplated by the inventors that various substitutions, alterations, and modifications may be made without departing from the spirit and scope of the invention as defined by the claims. By way of non-exclusive example, air vent control may be provided with sufficient programming to automatically close, without the need for a signal from central control when the temperature of the radiator reaches or exceeds a predetermined temperature. By way of another non-exclusive example, in large structures, the system may employ one or more repeater units for receiving and retransmitting communications between central control and the various air vent controllers. The repeaters may be configured to receive and retransmit using the same transmission format (e.g. RF) or it may be configured to receive in one format and retransmit in another format, similar to the room units described herein. With still another non-exclusive example, the system may employ other forms of transmissions such as frequency modulations (FM), etc. Other aspects, advantages, and modifications are considered to be within the scope of the following claims. The claims presented are representative of the inventions disclosed herein. Other, unclaimed inventions are also contemplated. The inventors reserve the right to pursue such inventions in later claims.
Insofar as embodiments of the invention described above are implemented, at least in part, using a computer system, it will be appreciated that a computer program for implementing at least part of the described methods and/or the described systems is envisaged as an aspect of the invention. The computer system may be any suitable apparatus, system or device, electronic, optical, or a combination thereof. For example, the computer system may be a programmable data processing apparatus, a computer, a Digital Signal Processor, an optical computer or a microprocessor. The computer program may be embodied as source code and undergo compilation for implementation on a computer, or may be embodied as object code, for example.
It is also conceivable that some or all of the functionality ascribed to the computer program or computer system aforementioned may be implemented in hardware, for example by one or more application specific integrated circuits and/or optical elements. Suitably, the computer program can be stored on a carrier medium in computer usable form, which is also envisaged as an aspect of the invention. For example, the carrier medium may be solid-state memory, optical or magneto-optical memory such as a readable and/or writable disk for example a compact disk (CD) or a digital versatile disk (DVD), or magnetic memory such as disk or tape, and the computer system can utilize the program to configure it for operation. The computer program may also be supplied from a remote source embodied in a carrier medium such as an electronic signal, including a radio frequency carrier wave or an optical carrier wave.
It is accordingly intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative rather than in a limiting sense. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention as described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between.
