An air conditioning system for use in an over-the-road or off road vehicle is provided that provides a method of operation during both engine on and engine off conditions. The method operates the air conditioning system at one capacity when the engine is running, and at a second capacity when the engine is not running. The selection of these capacities is based on the power capacity of the source of electric power from which the air conditioning system is operated. When a storage battery is used to power the air conditioning system during engine off conditions, the second capacity is lower than the capacity at which the system is operated when the engine is running.

Vehicle air conditioning and heating system providing engine on and engine off operation

An improved combined ambient-air and earth exchange heat pump system includes a subterranean heat exchanger (11) and an ambient-air heat exchanger (13), both refrigerant-based, which are adapted to be selectively operated individually, serially or in parallel for heating and cooling purposes. The system also includes a dynamic load heat exchanger (17), a reversing valve (9) for converting the system from heating to cooling and vice versa, storage for excess refrigerant including an accumulator (111), an optional preheat exchanger (37), a regulating assembly (59) with bleed port arrangement, a bypass mechanism (131) for repetitive start-up attempts, and a lost charge device (113). A control center (34) is provided to automatically activate the ambient-air heat exchanger (13) to assist the subterranean heat exchanger (11) after thermal stressing about the latter, to automatically deactivate the ambient-air heat exchanger (13) for ambient conditions below a preset temperature, to increase or decrease the number of tubes (92) used by the subterranean heat exchanger (11).

Combined ambient-air and earth exchange heat pump system

An improved geothermal heat exchange unit, which can be placed in ground and/or water, has a rigid hollow core about which is formed a helical winding of thermally conductive tube. The return section of the tube extends vertically along a central axis of the core, separated from the inner wall of the core by thermal insulating material. The heat exchange unit is optionally encased in a solid thermally conductive casing and may have a small diameter oil return tube from the lowermost portion of the unit to the suction intake port of a gas compressor. An optional high pressure water hose is attached for installation assistance in wet sand or wet soils.

Geothermal heat exchange unit

An coaxial-flow heat exchanging structure having a proximal end and a distal end for exchanging heat between a source of fluid at a first temperature and the environment (e.g. air, ground, water, slurry etc.) at a second temperature. The coaxial-flow heat transfer structure comprises: a thermally conductive outer tube section, and an inner tube section having an inner flow channel and being coaxially arranged within the outer tube section. An outer flow channel is formed between the inner and outer tube sections, and helically-extending turbulence generator is provided along the outer flow channel, so as to create turbulence along the flow of heat exchanging fluid flowing between the inner and outer flow channels, and thereby increasing the heat transfer through the walls of the outer tube section to the ambient environment.

Coaxial-flow heat transfer structures for use in diverse applications

A heating, ventilating and air conditioning (HVAC) system for use in an over-the-road or off road vehicle is provided. The HVAC system may be operated regardless of the operational state of the engine. That is, the HVAC system may be operated to condition the interior compartments of an over-the-road vehicle while the engine is running and while the engine is in a no-idle (off) condition. In general, the HVAC system efficiently shares one or more typical air conditionings components with those already found in the vehicle. In one instance, the HVAC system operates an electrically-driven compressor when a belt-driven compressor is idle. In another case, the HVAC system operates both an electrically-driven compressor and a no-idle condenser when a belt-driven compressor and condenser are idle. In yet another embodiment, the HVAC system shares an evaporator.

Vehicle air conditioning and heating system providing engine on and off operation

A heating and cooling method and apparatus for a single, closed loop configuration for directly exchanging thermal energy with the earth for both heating and cooling purposes. A refrigerant, which is pumped through the apparatus by a compressor, undergoes two phase transitions during each circuit through the loop. A subterranean heat exchanger has a pair of manifolds in flow communication with a plurality of substantially horizontally oriented tubes. Refrigerant flowing through the tubes has sufficient velocity to sweep lubricant oil, which has escaped from the compressor, along with it for return to the compressor. An expansion valving assembly automatically meters and regulates the flow rate and pressure of the refrigerant during both the heating mode and the cooling mode of the apparatus. A refrigerant storage device automatically supplies or accepts the change in quantity of the refrigerant required when the apparatus changes from either the heating or cooling mode to the reverse mode. A bypass mechanism anticipates the low pressure condition which arises at the compressor input during reversal or startup of the apparatus and provides multiple attempts to overcome inertial resistance corresponding thereto. A modified embodiment of the apparatus provides a non-phase-change heat exchanger flow communicating in tandem to remove a portion of the thermal energy for auxiliary thermodynamic purposes.

William E. Dressler

Papers

Heating and cooling apparatus