The present invention relates to the field of a refrigerant-to-air device that works in conjunction with earth-coupled heat pumps, to dissipate a portion of the heat otherwise intended to be rejected in the earth.
FIG. 1 is a diagram of the components, the refrigerant circuit, and the electrical connections.
In FIG. 1, the parts are numbered as follows:
- 10 . . . Compressor
- 12 . . . Auxiliary Cooling Module (ACM)
- 27 . . . Electronic Motor Control Unit (EMCU)
- 11, 13, 16, 18, 20, and 22 . . . Refrigerant conduits
- 14 and 15 . . . Earth loop conduits
- 17 . . . Expansion Valve or Liquid Flow Control
- 19 . . . Evaporator
- 21 . . . Accumulator or Active Charge Control
- 29 . . . Temperature Sensor
- 30 . . . Pressure Sensor
- 23 . . . Wiring from temperature sensor to EMCU
- 24 . . . Wiring from pressure sensor to EMCU
- 25 . . . Power cable from the EMCU to blower inside the ACM
- 28 . . . Surface of Earth.
In FIG. 2, the parts are numbered as follows:
- 35 . . . Fan coil
- 36 . . . Inlet manifold
- 37 . . . Outlet manifold
- 38 . . . Refrigerant tubing
- 39 . . . Refrigerant outlet
In FIG. 3, the parts are numbered as follows:
- 50 . . . Fan and Fan coil arrangement
- 51 . . . Fan motor
- 53 . . . Fan blades
- 37 . . . Side view of Fan coil outlet manifold
- 39 . . . Fan coil outlet.
In FIG. 4, additional parts are:
- 31 . . . Refrigerant-to-water heat exchanger
- 32 . . . Water circulating pump
- 33 . . . Underground water loop
In FIG. 5, additional parts are:
- 36 . . . Power cable from wattage sensor to EMCU
- 34 . . . Power inlet cable
- 35 . . . Wattage sensor
- 36 . . . Wiring from wattage sensor to EMCU
- 37 . . . Power cable from wattage sensor to compressor
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The operation of the system is a follows:
With reference to FIG. 1, the unwanted heat is absorbed by the refrigerant in the evaporator 19. The refrigerant is then drawn through Active Charge Control (ACC) 21, and on to the compressor 10, via conduits 20 and 22. The hot compressed vapor then leaves the compressor through conduit 11 to the Auxiliary Cooling Module (ACM) 12. The ACM removes superheat from the refrigerant vapor, and the heated vapor proceeds onward to earth loop 14 and 15, where the remaining heat is dissipated within the earth 28, where the vapor is condensed back to liquid refrigerant. The liquid then flows via conduit 16 to the Liquid Flow Control (LFC) 17, which regulates the amount of refrigerant required by the evaporator 19. The refrigerant then flows on to the evaporator 19 via conduit 18 to complete the cycle. The LFC 17 and the ACC 21 work in concert to require the condenser (earth loop 14, and 15) to be fully condensing and the evaporator 19 fully wetted, such that all inactive liquid refrigerant resides in the ACC, and an optimum amount of refrigerant is in active circulation under all operating conditions, and the ACC provides storage for inactive liquid refrigerant to provide for all operating conditions, plus any desired amount of reserve refrigerant charge.
Pressure sensor 30 transmits a pressure signal via wiring 24 to The Electronic Motor Control Unit (EMCU) 27, or temperature sensor 29 transmits a temperature signal via wiring 23 to the EMCU 27. The purpose of the EMCU 27 is to turn the fan motor 51 on or off and modulate the electrical power that enters the EMCU by power entrance cable 26 and then flows from the EMCU via power cable 25 to a fan within the ACM 12. Within the EMCU is an electronic control (not shown), that uses pressure or temperature signals to regulate the speed of the fan motor 51 by controlling the amount of electrical power that flows on to the fan within the ACM. The electronic control modules are off-the-shelf modules that are generally readily available, leaving no need to describe the details of such modules. The amount of power delivered to the fan may vary from zero (off) to full power, thus allowing the ACM 12 to remove the optimum amount of unwanted heat from the hot vapor, to achieve a predictable system capacity and efficiency. Improving efficiency by use of the ACM can allow fewer earth loops for a given system capacity, which can result in a reduced overall system cost.
Alternatively, the LFC 17 may be replaced with other expansion devices such as a capillary tube, TXV (Thermostatic expansion valve), or a fixed orifice, and the ACC 21 may be replaced with a liquid/vapor separator such as an accumulator. For a system with these refrigerant controls, it is necessary to calculate a fixed refrigerant charge for the system, the amount of charge that will provide the best average efficiency as the systems operates through the whole range of operating conditions.
With reference to FIG. 2, the Fan coil 35 receives hot vapor at inlet manifold 36, then the hot vapor flows through multiple tubes 38, where air blowing between the tubes absorbs and removes heat. The tubes may be finned (not shown) for maximum heat removal. The vapor flows from the tubes into outlet manifold 37, and exits the Fan coil at exit stub 39.
FIG. 3 is a side view of Fan and Fan coil 50, viewed from the exit manifold 37 side of the Fan coil. The fan motor 51 rotates the fan blades 53, to force air through the fan coil 35 (FIG. 2). The refrigerant vapor exits the fan coil at exit stub 39.
With reference to FIG. 4, another embodiment of the invention dissipates the unwanted heat into the earth by way of a heat exchanger 31 and water loop circuit. In this configuration, the hot vapor leaving the ACM 12 is conveyed via conduit 12 to the primary side of heat exchanger 31, wherein the vapor is condensed back to a liquid and the liquid refrigerant proceeds via conduit 16 to the expansion valve 17, to complete the cycle. The unwanted heat is transferred to the secondary side of the heat exchanger. A water loop circuit consists of the secondary side of the heat exchanger 31, a circulating pump 32, and underground water loop 33. The pump 32 circulates water, or glycol or some other liquid through the circuit, thereby transferring the unwanted heat into the earth 28.
Yet another embodiment of the invention is shown in FIG. 5. All the components in FIG. 4 remain, and components 34, 35, 36, and 37 are added. In FIGS. 1 and 4, the function of holding the compressor output temperature and/or pressure to or below a desired limit, is provided by automatically or manually controlling the speed of the fan motor 51. The configuration of FIG. 5 further provides the function of automatically controlling the fan to a speed that results in the lowest power consumption incurred by the system. Power for the system enters through power cable 34, and proceeds through wattage sensor 35 to the EMCU 27 via electric power cable 26, and to the compressor 10, via power cable 37. Wattage sensor 35 then sends a signal representing the total power usage to the EMCU via wiring 36.
With this configuration, the EMCU is set to maintain a fan speed that gives the lowest system wattage input. When the pressure and/or temperature sensor reaches the desired limit, the EMCU will then respond to control the fan such that the desired limit is not exceeded. When the pressure and temperature are below the set limit, the AMCU will adjust the fan speed to a speed that reduces the total wattage to the system to a minimum, but not to a speed that allows the temperature or pressure to rise above the desired limits.