Conflated Air Conditioning System

Abstract

The primary object of the present invention is to provide a basis for the design and implementation of a heating and cooling system (air conditioning system) which will reduce energy consumption over the presently used systems, reduce equipment and installation cost, and reduce maintenance cost. The use of this invention can mostly be used (but not only) in any commercial or residential building requiring heating and cooling. This system allows heating and cooling with water-cooled, self-contained air conditioning units or heat pumps, served by 2-pipe or single pipe, viable without heat pump operation, and can utilize waterside economizer. The system eliminates the need of having separate condenser water and separate hot water piping connections to the self-contained terminal air conditioning units. In cooling mode, the 2-pipe system or the single pipe system serves as condenser water piping from the cooling tower, and at appropriate outdoor temperature the colder water is supplied through the same piping to the economizer coil, thus saving the compressor work. At heating mode, the 2-pipe system or single pipe system from the boiler serves as hot water piping to the same coil serving also as the economizer coil.

Description

This invention relates to a system for those providing cooling and heating by water-cooled self-contained air conditioning units or heat pumps, having economizer coil in such a manner that condenser water source is the cooling tower, and heating source is the boiler, utilizing 2-pipe or single-pipe distribution arrangement.

BACKGROUND OF THE INVENTION

It is conventional practice utilizing the advantage of the 2-pipe distribution arrangement for water-cooled, self-contained air conditioning units. When at heating mode the units are working in heat pump mode. Boiler provides the absorption heat for the heat pump operation in addition to the heat that is provided from the units still operating in simultaneous cooling mode. The electric power consumption of the heat pump compressor all year long makes its operation very expensive. The economic advantage of the less expensive initial installation cost is lost by the higher energy consumption costs.

A Customary system using cooling only water-cooled self-contained units with hydronic heating, is served by separated condenser water and separate hot water piping for optimum energy consumption costs, but the 4-pipe distribution arrangement and two separate coils increases its installation costs.

An Economizer coil of the water-cooled self-contained units is customized for providing free cooling at cooling mode, when the condenser water temperature is cool enough.

The object of the present invention is to combine all the advantages of the less expensive piping distribution and component arrangement, combine functions of the economizer coil, lower energy consumption costs, make use of the free cooling of the economizer coil, which is also used as a heating coil, and in this way to make it possible to achieve less expensive energy consumption costs alongside with minimal installation and equipment costs.

SUMMARY OF THE INVENTION

A System constructed in accordance with the invention compromises a 2-pipe or single-pipe distribution arrangement serving water-cooled air conditioning self-contained units with economizer coil or water-cooled self-contained heat pumps with economizer coils. In cooling mode the distributing piping is connected to the cooling tower and serves as condenser water piping. When the condenser water temperature is cool enough, the condenser water is directed throughout the economizer coil. In heating mode, the distribution piping is connected to the boiler and the water again will be directed throughout the economizer coil serving as heating coil. In practical composition of the invention, the cooling tower and/or the boiler can be connected to the distribution piping over with an inserted heat exchanger. For simulations heating and cooling operation of some unit, heat pumps are connected to the piping. Pumps are circulating the water in the distribution piping. Valves serve to separate equipment from piping.

Detailed Description of a Conflated Air Conditioning System

The most economical air conditioning system in today's buildings, in terms of both cost of installation and yearly operation costs, is a Conflated System. With a better insulated building and the use of heat recovery ventilation, we reduce the ratio of heating load to cooling load. The result is a more economic operation of the building system which translates into significant beneficial economic impact. The Conflated System utilizes the readily available self-contained water cooled heat pump units and fits them with economizer coils both for cooling and for heating, thus utilizing a cost effective single-water distribution piping network. It provides the highest thermal efficiency through the use of evaporating cooling of the cooling tower and through the use of the condensing boiler.

The operation method of the Conflated System in a building, for example a hotel, is the following. After conventional summer operation, the economizer coils can serve for free cooling when the outside temperature allows cooling down the circulated water to around 60° F. The low outdoor absolute humidity starts the vapor migration from the building to the outside and the latent load is diminishing. The sensible load can be handled by higher temperature chilled water. Thus, this procedure requires no compressor operation in the building. When heating is required in certain specific rooms, they can be heated by heat pump operation. During this time only the compressors in these rooms are operating.

During this period, when the cooling load dominates, it needs to cool the circulating water by the cooling tower to prevent its temperature from elevating.

When the cooling requirement turns minimal and the heating load is prevailing, the temperature of the circulated water tends to drop and to maintain its temperature it has to be heated. When heating of the circulated water is required, it will be heated up to warm temperature by the boiler and directed through the coil and controlled in a similar way as conventional 2-pipe fan coils for heating. In the rooms where cooling is still required, the units in there will be running in cooling mode when the compressors, in these rooms only, are needed to operate. During this time, the rejected heat of the units in cooling mode reduces the load of the boiler.

The automatic control of the heat pumps shall be as follows. There is a manual change over from Cooling Mode to Heating Mode of the unit. When the compressor is on, water flows through the refrigerant heat exchanger and the fan is activated. The water flow is closed through the refrigerant heat exchanger by time delay when it is diverted to the economizer coil.

In Cooling Mode: If water temperature is cooler than the space thermostat set point, the water flows through the economizer coil and fan, cycled by the space thermostat to maintain space temperature set point. When a rise in space temperature occurs, water flow bypasses the economizer coil and the compressor is sequenced by the space thermostat. If water temperature is higher than the space thermostat set point, water flow bypasses the economizer coil and the compressor is sequenced by space thermostat.

In Heating Mode: If water temperature is cooler than the space thermostat set point, water flow bypasses the economizer coil and the compressor is sequenced in heat pump mode by the space thermostat. If water temperature is higher than the space thermostat set point—water flows through the economizer coil and fan, cycled by thermostat (in heating mode).

As an option, especially for larger units, a temperature control of the economizer coil, through a water side-flow control with proportional or incremental actuator of the water valve, controlled the from space thermostat, can be provided.

For condenser water pump economy, the water valve is closed when the fan is off and it is open when the fan is activated.

Circulated Water Temperature Control can work as follows.

Condenser water discharge temperature during cooling season is 85° F., controlled by cooling tower fan operation. In economizer mode, temperature is in the region of 55°-60° F. It can be maintained as well during cold winter conditions by directing the water flow, either up to the cooling tower nozzles over the fill or down to the basin, by alternating the two-position condenser water directing valve. At heating mode, the distributed water temperature is elevated up to around 100° F. by the boiler and can have outdoor temperature setback.

From an operational point of view, when the circulated water temperature drops under the set-point of the economizer mode, the system should switch to heating mode and when the temperature set point is elevating above heating mode set-point, the system should switch to economizer mode. For preventing sort cycling, about a 5° F. temperature-span delay should be provided before switching for changeover.

Conflated System exploits all the advantages of the conventional water loop heat pump, providing a low construction cost of its water circulation loop, where the single circulation system is either cooled by cooling tower or heated by the boiler.

The operation costs of a Conflated System, however, are significantly lower than the conventional water loop heat pump systems. The operation costs of the Conflated System are lower than the operation costs of water source self-contained systems, which need a costly separate condenser water loop with a cooling tower for cooling and another separate loop with the boiler for heating. At times, the Conflated System even works like a 2-pipe fan coil system does in a chiller system.

The Conflated System uses the newly available contemporary heat pumps, which can operate for cooling with 40° F.-110° F. condenser water temperature and for heating with 30° F.-80° F. entering water temperature. These products are available with factory made economizer coils.

When comparing the yearly operation costs of the conventional heat pump systems where the compressor runs year around, in the winter for heating and in the summer for cooling, to the Conflated Systems, where the compressors only run limited time and only in limited units, the cost difference is significant. Even, in ideal situations for conventional heat pumps application, where the cooling load just compensates the heating load, the Conflated System is still significantly more economical. Using the economizer coils for cooling, the heat generated at the coils also compensates the absorption load of the heat pumps operating in heating mode. At those time, with the conventional heat pump system, all compressors are running, but with the Conflated System roughly only half of the units' compressors have to be operated.

In addition to the initial lower installation cost, utilizing a single circulating loop results in favorable operating expenses by saving significant compressor operations, thus the conflated system provides more savings. By using only limited hot water temperature, the condensing boiler can operate season round on condensate mode, with best efficiency. This is significant for historic buildings especially, where the circulating system can be single pipe with the Taco LoadMach method. Any of the single units can be operated in either heating or cooling mode anytime of the year according to the occupants' desire. During most of the year, units can be operated with a reduction of noise, when no compressor in the unit is operating. Fewer compressors wearing down corresponds to reduced maintenance costs. The emergency generator can be much smaller if considering critical heating requirements in the building. A Conflated System can be built with all American-made equipment.

THE DRAWINGS

A System constructed in accordance with the invention is illustrated in the accompanying drawing wherein:

FIG. 1 is a diagrammatic illustration of the 2-pipe distribution system of the cooling and heating units.

FIG. 2 is a diagrammatic illustration of the single-pipe distribution system of the cooling and heating units.

THE PREFERRED EMBODIMENT

A System constructed in accordance with presently preferred embodiment of the invention is illustrated in FIG. 1 and FIG. 2. as being associated with the water-cooled self-contained air conditioning or heat pump units-1, the cooling tower-2, the boiler-3, and the economizer coils-4, fluid circulators-5, and pumps-6 are maintaining the flow in the distribution piping. Heat exchanger-7 may be dividing the direct circulation with valve-8 thus far described is conventional.

The arrangement illustrated by only one 2-pipe or one single-pipe riser, but at a practical completion of the system, may be grouped with several similar risers. At a commensurate implementation of the method, the illustrated system may be connected to a conventional heat pump system as a sub-division.

The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims.

Claims

1. Air conditioning and heating system compromising of: water-cooled self-contained air conditioning unit or heat pump with economizer coil; cooling tower; boiler; circulating pumps; the system components are connected with 2-pipe or single-pipe distribution piping with valves as condenser water piping, or hot water piping.

2. The system as recited in claim 1, wherein the distribution piping is furnished with valves that can direct or control the flow to the condenser, or to the evaporator, to the economizer coil which serves both as cooling coil and heating coil, to the cooling tower, to the boiler.

3. The system according to claim 2, wherein heat exchanger is inserted into distribution piping, or circulator is inserted to single-pipe distribution piping connected to air conditioning unit, or to heat pump, or expansion tank is connected to piping.