Patent Publication Number: US-2005126630-A1

Title: Automatic freeze protection system for plumbing systems

Description:
RELATED APPLICATIONS  
      This application is a Continuation-In-Part of U.S. Ser. No. 10/420,213. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Technical Field  
      This invention is related to domestic plumbing systems, and in particular to an apparatus and method for protecting a home or other building from the extensive damage that can result from the freezing and resulting bursting of pipes within walls and ceilings of a building. The apparatus is portable such that one apparatus may be utilized in several locations.  
      2. Field of the Invention  
      A typical domestic plumbing system receives water from a municipal supply system or a well, and then distributes the water as hot and cold water to fixtures throughout the house. The piping that makes up the plumbing system is installed within the walls and ceilings of the building for cosmetic purposes. Such systems work very well, and provide reliable service under most conditions. One potential problem with such systems arises if and when the heating system in the building fails, and the internal temperature of the building falls below freezing. If this occurs while the building is unoccupied, the pipes can freeze and burst, causing extensive damage to the building. The damage can be particularly severe if the water service to the building has not been turned off at the supply valve, in which case water will continue to flow into the building until the leak is discovered hours or even days later.  
     BRIEF SUMMARY OF THE INVENTION  
      This invention addresses this problem by providing a plumbing system that includes an antifreeze dispensing apparatus that can be activated to inject a predetermined amount of antifreeze into the plumbing system and prevent the freezing of the pipes and fixtures. The antifreeze is a nontoxic antifreeze that is approved for domestic use, and that can be readily flushed from the system using only fresh water form the normal supply. In another aspect of the invention, the apparatus senses when the temperature in the building has dropped to freezing and automatically shuts the water supply valve to the plumbing system. In yet another aspect of the invention, the major components of the apparatus are portable so that a single apparatus may be utilized in several different locations. These and other features of the invention will be described in greater detail be reference to the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The nature, principle and utility of the present invention will be clearly understood from the following detailed description when read in conjunction with the accompanying drawings, wherein:  
       FIG. 1  is a schematic drawing of a typical domestic plumbing system including various domestic appliances and fixtures, and the required hot and cold water supply lines.  
       FIG. 2  is a schematic drawing of a domestic plumbing system according to a preferred embodiment of the present invention.  
       FIG. 3  is a front view of a system controller.  
       FIG. 4  is an enlarged perspective view of connections between the bypass valve assembly, the water heater and the water supply shown in  FIG. 1 .  
       FIG. 5  is a partial cut away view of the bypass valve.  
       FIG. 6  is a perspective view of the portable antifreeze protection system.  
       FIG. 7  is a perspective view of the portable antifreeze protection system as shown in  FIG. 6  with the cover in place.  
       FIG. 8  is a front view of the quick connect winterize valve.  
       FIG. 9  is a front view of the hot water heater bypass valve. 
    
    
      The drawings are for illustrative purposes only and are not drawn to scale. In the drawings, the same numbers are used for the same part or portion throughout the drawings.  
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
      Turning now to  FIG. 1 , a typical domestic plumbing system includes a water supply  10 , a water supply cut-off valve  12 , backflow preventer, and separate hot and cold water supply piping systems  14  and  16  respectively. The hot water system  14  includes a hot water heater  18 , a cold water supply  20  to the water heater  18 , and a hot water supply piping system to supply hot water to appliances such as the dishwasher  22 , clothes washer  24 , sinks  26  in the bathrooms and kitchen, and bathtubs  28 . The cold water supply piping system  16  supplies cold water to each of these same appliances and fixtures, and also to toilets  30  and hose bibs  32 .  
      In one preferred embodiment of the invention, shown in  FIG. 2 , a freeze protection system includes, in addition to the components enumerated for the typical domestic plumbing system, a cold water supply valve controller  34 , an antifreeze storage tank assembly  36 , a bypass valve assembly  38 , and a controller assembly  40 . The water supply valve controller  34  includes a water supply shut off valve (not shown). An antifreeze supply line  42  connects water supply valve controller  34  to the antifreeze storage tank assembly  36 . The antifreeze storage tank assembly  36  includes a pump (not shown) to dispense antifreeze within the storage tank assembly  36  through line  42  to the water supply controller valve  34  and into the water supply line  35 . The pump is preferably a low voltage pump that is supplied with low-voltage current from a transformer connected to the building&#39;s electrical system (not shown) under normal operation. In the event of a power outage, the storage tank assembly  42  includes a backup battery (not shown) for operating the pump.  
      Referring to  FIGS. 4 and 5 , bypass valve assembly  38  includes an electrically operated three-way valve that can be configured to direct a supply of cold water into the water heater  18  under normal operation, and to bypass the water heater  18  and redirect cold water directly into the hot water piping system  16 . Bypass valve  38  in the preferred embodiment is a three way ball valve with its inlet  39  connected to the cold water inlet line from the water supply controller valve  34 . One outlet  41  of bypass valve  38  directs cold water to the hot water heater  18  under normal conditions. A second outlet  43  directs cold water to bypass water heater  18  and go directly into the hot water system of the building. This configuration is used to introduce antifreeze into the hot water system of the building. A check valve  51  is installed between the water heater hot water outlet  53  and bypass valve  38  to prevent backflow into the water heater discharge from the bypass valve. Referring to  FIG. 5 , bypass valve  38  includes a ball assembly  45  that is rotated between the first and second configurations by actuator  47 . Actuator  47  is connected by wires  49  to controller assembly  40 , which operates the bypass valve as described below.  
      The controller assembly  40  is preferably an electronic as shown  FIG. 3 . Controller  40  includes an outside temperature monitor  42 , an antifreeze level indicator  44 , an inside temperature monitor  46 , a switch  48  to initiate the winterization process, a switch  50  to activate the bypass valve assembly  38 , a switch  52  to activate the battery backup for antifreeze injection pump, and a water damage control switch  54  to activate the water supply controller valve  34  in order to isolate the plumbing system from the water supply system if temperatures drop to −30° F.  
      The operation of the system will now be described. Under normal operation, water supply controller  34  directs water from the water supply system to the plumbing system. Cold water is directed into the cold water piping system  16 , and also through bypass valve assembly  38 , hot water heater  18  and into the hot water piping system  14 .  
      When the building is going to be unoccupied for a period of time in which it would be possible for the plumbing system to be exposed to freezing temperatures, the user presses the bypass switch  50 , followed by the winterize switch  48 . The system is activated to configure bypass valve assembly  38  to redirect water away from the hot water heater and directly into the hot water piping system  14 . The system then activates the antifreeze pump to supply antifreeze from storage tank assembly  42  to the water supply controller, which injects the antifreeze into the water entering the plumbing system of the building. Water valves on the appliances and fixtures are then opened to permit the water/antifreeze solution to flow through and fill the plumbing system, and are then closed. The hot and cold water piping systems are then protected from freezing temperatures. Applicant has found that a ratio of 50% propylene glycol is suitable for protecting the system to a temperature of about −50 F. A higher concentration of antifreeze can be obtained by adjusting the water supply controller  34  to inject a greater amount of antifreeze into the water entering the system. In this way the system can be protected to a temperature of −60° F. Once the plumbing system has been flushed with the antifreeze mixture, the valves on the appliances and fixtures are closed. The water supply controller  34  is then activated again, and shuts the water supply valve, protecting the system in the event of a leak in the system during the owner&#39;s absence. The winterize injection switch also deactivates the pump in the antifreeze storage assembly  36 . The water heater can be turned off and drained since it is isolated from the rest of the system.  
      When the building is to be reoccupied, the bypass switch  50  is activated, configuring the bypass valve  38  to its bypass operating configuration. The winterize switch  48  is activated to normal flow to open the water supply valve. The water valves at each appliance are opened to permit fresh water to completely flush the antifreeze from the system in preparation for normal use of the building. After flushing is complete, the bypass  50  is activated to normal flow position and the water heater will fill at this time.  
      In the preferred embodiment the system is activated and controlled by a 12 volt electrical system. In other embodiments some or all of the system configuration and activation can be done manually.  
      Some functions of the system can be activated individually. For example, if the building is to be unoccupied, but freezing is not a concern the water damage control switch  54  can be activated to shut off the water supply to the building while unoccupied. If it is necessary to service the water heater, the bypass valve can be operated separately to isolate the water heater from the rest of the system. Finally, if power to the building is interrupted, the water damage control  54  will activate closing the flow of water supply.  
      In an alternate embodiment, the major components of the apparatus are assembled and mounted on a cart so that a single apparatus may be utilized in several locations. As shown in  FIG. 6 , the antifreeze storage tank  36 , the pump  64 , the battery  66 , a converter  68  and a charger  69  are included in a portable unit  60 . The portable unit  60  includes a cover  61 . As shown in  FIG. 7 , when the cover  61  is engaged on the portable unit  60 , controller  40  is accessible. The controller  40  is operated manually and generates electrical signals to configure the system. The controller  40  includes an antifreeze level indicator  44 , a switch  48  to initiate the winterization process, and an antifreeze switch  50 , as discussed in more detail in reference to  FIG. 3 . The portable unit  60  also includes an antifreeze fill port  72  and an antifreeze injection hose  74 .  
      The portable unit  60  may be plugged in to an electrical outlet at the desired location with cord and plug  76 . In the event of a power failure, the controller  40  will direct the back-up battery  66  to operate the pump  64 .  
      One advantage of the portable unit  60  is that one unit may be utilized in several different locations. For example, it may be desirable to winterize several buildings in several different locations. The portable unit  60  may also be used winterize the plumbing system of a vehicle, such as an RV or a boat. The various locations would have a quick connect assembly as a permanent fixture. The portable unit  60  can easily be connected to the quick connect assembly in order to perform the winterization process.  
      Quick connect assembly  80  is depicted in  FIG. 8 . The incoming water supply line is connected at inlet  82  and the water supply exits at outlet  84 . Outlet  84  is connected to the plumbing system of the building or vehicle. The antifreeze injection hose  74  of the portable unit  60  can be connected at inlet  86  for performing the winterization process.  
      The building or vehicle may also have an electric hot water heater bypass valve as depicted in  FIGS. 4 and 5 . Alternatively, the hot water heater bypass valve may be manual, such as the valve assembly  90  depicted in  FIG. 9 . In the manual hot water heater bypass valve assembly  90 , the water supply enters at inlet  92 . Under normal operation, the water supply exits the bypass valve  98  and enters the hot water heater at outlet  94 . For winterization purposes, the lever  97  is activated so that antifreeze enters the assembly  90  at the inlet  95 , passes through the valve  98  and enters the plumbing system at outlet  96 , thereby bypassing the hot water heater.  
      The operation of the portable system  60  will now be described. Under normal operation, water is directed from the water supply inlet  82  of the quick connect assembly  80  to the plumbing system of the location via outlet  84 . Quick connect assembly  80  is a permanently installed fixture at the location. Cold water is directed into the cold water piping system, and also through bypass valve assembly  90 , hot water heater and into the hot water piping system.  
      When the location is going to be unoccupied for a period of time in which it would be possible for the plumbing system to be exposed to freezing temperatures, the user connects the antifreeze injection hose  74  of the portable unit  60  to the quick connect inlet  86 . Then, the user switches the lever  97  on the hot water heater to the bypass position so that water is redirected away from the hot water heater and directly into the hot water piping system. Then, the user presses the antifreeze switch  50 , followed by the winterize switch  48 , so that the antifreeze pump  64  supplies antifreeze from storage tank  36  to the plumbing system of the location. Water valves on the appliances and fixtures are then opened to permit the water/antifreeze solution to flow through and fill the plumbing system, and are then closed. The hot and cold water piping systems are then protected from freezing temperatures. Applicant has found that a ratio of 50% propylene glycol is suitable for protecting the system to a temperature of about −50 F. Once the plumbing system has been flushed with the antifreeze mixture, the valves on the appliances and fixtures are closed. The winterize injection switch then deactivates the pump  64  in the portable unit  60 . The water heater can be turned off and drained since it is isolated from the rest of the system.  
      When the location is to be reoccupied, the lever  97  on the hot water heater bypass valve  90  is switched to the bypass operating configuration. The winterize switch  48  is activated to normal flow to open the water supply valve. The water valves at each appliance are opened to permit fresh water to completely flush the antifreeze from the system in preparation for normal use of the building. After flushing is complete, the lever  97  on the hot water heater bypass valve  90  is switched to the normal flow position and the water heater will fill at this time.  
      The antifreeze solution can be any suitable solution approved for domestic potable water systems. Applicant has identified prop glycol, available from Dow Chemical, as one such preferred antifreeze solution.  
      While the invention has been described by reference to the foregoing preferred embodiments, the invention is not intended to be limited thereby. Those of skill in the art will understand that numerous modifications and variations are possible without departing from the scope of the following claims.