Abstract:
A chiller heater building air space conditioning system is set out including a plurality of interconnected modular chiller/heater units which can be operated variously in a chilling mode, a heating mode, or an off mode. An arrangement for converting a system comprising reversible modular heat pump chiller heater elements into a system comprising non-reversible modular chiller heater elements is set out.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to an apparatus and method for converting a modular reversing chiller/heater system to a modular non-reversing chiller heater system. 
         [0003]    2. Description of the Related Art 
         [0004]    In the past, various systems have been proposed for providing an energy efficient system for building air space conditioning, where a building may require variously simultaneous heating and cooling. Such systems are set out, for example, in U.S. utility patent application Ser. No. 12/562,931 and U.S. provisional patent application number 61/447,247. 
         [0005]    The first such system in the world to utilize a plurality of modular reversible heat pump chiller heater units utilizing a system of virtual moveable endcaps is described in U.S. Utility patent application Ser. No. 12/562,931. This application disclosed for the first time an arrangement of interconnected reversible heat pump chiller heaters having on one side of each modular unit one or more building conditioning fluid loop connections for alternately chilling or heating building/conditioning fluid. The system allows for each modular unit to be operated and interconnected in a manner by which flexibility in providing various arrangements of heating, cooling, and simultaneous heating and cooling to a building is provided, as well as selective resting of particular units. 
         [0006]    A ground or water source heat sink/source could be variously utilized on the other side of each modular unit opposite the building load. 
         [0007]    This system provided many advantages but meanwhile suffered from certain drawbacks, one of which was that by virtue of the reversible nature of the individual modular units, significant design compromises were inherent which led to a reduced energy efficiency compared to non-reversing units. 
         [0008]    An improved system was set out in U.S. Provisional Patent Application No. 61/447,247, whereby the flexibility of interconnected modular units could be realized, but which for the first time disclosed an arrangement whereby each modular unit was a non-reversing chiller heater, instead of a reversing heat pump chiller heater. This system realized significant gains in energy efficiency over the previously disclosed reversing system. 
         [0009]    Meanwhile, a need existed to allow for the conversion of the relatively inefficient modular reversing heat pump chiller heater system to a non-reversing mode, in order to realize the inherent efficiency advantages. 
       BRIEF SUMMARY OF THE INVENTION 
       [0010]    In view of the aforementioned drawbacks in certain prior art chiller heater systems, a new system is proposed which achieves the objects of flexibility and energy efficiency. 
         [0011]    It is an object of the invention to set out a system of interconnected modular chiller heater units which can variously be operated to provide chilling, heating, and/or simultaneous chilling and heating to a building load, as well as resting of particular units. 
         [0012]    Specifically, it is an object of the invention to set out a system of interconnected reversible heat pump chiller heater units which are originally installed in an arrangement whereby each unit is operable in a reversible mode, and which by virtue of the present invention are modified to operate in whole or in part as non-reversing units. 
         [0013]    More particularly, it is an object of the invention to set out a system which converts a system of interconnected modular reversible heat pump chiller heaters utilizing a ground or water source heat sink/source to a system of non-reversing chiller heaters capable of being selectively operated to variously provide cooling, heating, simultaneous cooling and heating, or to be rested as required. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEW OF THE DRAWINGS 
         [0014]      FIG. 1  is a schematic drawing of a prior art arrangement of interconnected reversible modular heat pump chiller heaters. 
           [0015]      FIG. 2  is a schematic drawing of a modification of prior art arrangements of interconnected reversible modular heat pump chiller heaters. 
           [0016]      FIG. 3  is a schematic drawing of a reversing system converted to a non-reversing system. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    Following is a listing of elements of the invention.
     1 . Building to be conditioned     2 . Second side building fluid manifold     3 . First side building heat exchanger     4 . Second side building heat exchanger     5 . First side evaporator/condenser     6 . Second side condenser/evaporator     7 . Alternate chilled fluid/heat sink/source three way valve     8 . Ground/water heat sink/source     9 . Ground/water heat sink/source heat exchanger     10 . Reversing refrigerant working fluid loop     11 . Alternate heated fluid/chilled fluid three way valve     12 . Second side reversible chiller heater isolation valve     13 . First side reversible chiller heater isolation valve     14 . Building conditioning fluid loop     15 . Virtual moveable endcap building fluid isolation valves     16 . Chilled fluid isolation valve     17 . Heated fluid isolation valve     18 . Heated fluid bypass circuit     19 . Heated fluid bypass circuit isolation valve     20 . Heated fluid building load isolation valve     21 . Alternate chilled fluid/heat sink/source three way valve     22 . Heat sink/source isolation valve     23 . Non-reversing refrigerant working fluid loop     24 . Evaporator     25 . Condenser     26 . Chiller/heater module     27 . Modular reversing heat pump chiller/heater     28 . First side building first fluid manifold     29 . First side building second fluid manifold   
 
         [0047]      FIG. 1  sets out a prior art modular reversing virtual moveable endcap chiller heater system, as set out in U.S. Utility patent application Ser. No. 12/562,931. 
         [0048]    A series of chiller/heater modules  26  are arranged to variously be employed to provide chilled or heated building conditioning fluid via a building conditioning fluid loop  14  to a first side building heat exchanger  3 , a second side building heat exchanger  4 , or a ground water heat sink/source heat exchanger  9 . A modular reversing heat pump chiller/heater  27  includes a reversing refrigerant working fluid loop  10 , a first side evaporator/condenser  5 , and a second side condenser/evaporator  6 . 
         [0049]    Modular reversing heat pump chiller/heater  27  can be operated in one direction to evaporate working fluid in the first side evaporator/condenser  5  and condense working fluid in the second side condenser/evaporator  6 , and can alternately be operated in the opposite direction, by reversing the flow direction of working fluid in the reversing refrigerant working fluid loop  10 , to evaporate working fluid in second side condenser/evaporator  6 , and condense working fluid in the first side evaporator/condenser  5 . 
         [0050]    Virtual moveable endcap valves  15  can be operated to variously deliver heated or chilled building conditioning fluid to the first side building heat exchanger  3 , the second side building heat exchanger  4 , and/or the ground water heat sink/source heat exchanger  9 , depending on the requirements of the building cooling load, heating load, ambient conditions and energy cost considerations. 
         [0051]    Also, first side reversible chiller heater isolation valve  13  and second side reversing chiller heater isolation valve  12  can be operated to fully or partially add or remove the energy transfer effect of the respective first side evaporator/condenser  5  and second side condenser/evaporator  6  from contribution to the building conditioning fluid. 
         [0052]    In one embodiment, the conversion process from the reversing system of  FIG. 2  to the non-reversing system of  FIG. 3  is essentially as follows. 
         [0053]    Heated fluid bypass circuit  18  is attached in fluid connection with the previous connection between the second side condenser/evaporator  6  and the second side building fluid manifold  2 , and the first side building first fluid manifold  28 . 
         [0054]    Where in the pre-converted system, second side building fluid manifold  2  served the heat sink source  8 , in the post-converted system, the second side building fluid manifold  2  serves the building  1  second side heat exchanger  4 , normally to provide heat energy to the building space. 
         [0055]    In the pre-converted system, first side building first fluid manifold  28  served the second side building heat exchanger  4 , normally to provide heat energy to the building space. In the post-converted system, first side building first fluid manifold  28  serves the heat sink/source  8 . 
         [0056]    In both pre and post converted systems, first side building second fluid manifold  29  may serve the first side building heat exchanger  3 , normally to remove heat energy from the building space. 
         [0057]    The non-reversing refrigerant working fluid loop  23  would then be operated in such a manner that the previous reversing valve of the previous reversing heat pump chiller heater apparatus would not be required. The working fluid would be circulated such that it would transfer heat from itself through the condenser  25  to either the second side building fluid manifold  2  to heat the building, or to the first side building first fluid manifold  28  to be rejected into the heat sink source  8 . 
         [0058]    Simultaneously, the non-reversing refrigerant working fluid loop  28  would absorb heat through the evaporator  24 , to remove heat from either the first side building second fluid manifold  29  to remove heat from the building space, or from the first side building first fluid manifold  28  to remove heat from the heat sink source  8 . 
         [0059]    Via virtual moveable endcap building fluid isolation valves  15 , modular units  1 -n may be selected to variously add or reject heat to either the building space or to the heat sink source  8 . Also, individual chiller/heater modules could be rested as required. 
         [0060]    In this manner, a modular recovery heat pump chiller heater system may be converted into use as a modular non-reversing chiller heater system, with the attendant energy efficiency advantages of such a system.