Refrigerant system with tandem compressors and reheat function

Abstract

A refrigerant system incorporates at least two compressors that act in tandem to provide variable control over the refrigerant system performance. The tandem compressors can be of conventional or economized type and are configured for maximum performance utilization. Further, a reheat circuit can be incorporated into the refrigerant system at several different locations. The reheat cycle provides additional control over sensible and latent capacity of the refrigerant system, and is particularly advantageous when utilized in combination with the tandem compressors. As a result, multiple steps of unloading can be implemented in all operation regimes, the external load demands are satisfied with much greater precision, eliminating undesirable variations in temperature and humidity, system efficiency and reliability are augmented and equipment life-cycle cost is reduced.

Description

BACKGROUND OF THE INVENTION [0001] This invention relates to refrigerant cycles incorporating a reheat coil, and wherein a tandem compressor arrangement is utilized. The resulting cycles provide an enhanced control over both humidity and temperature in the conditioned space as well as improve efficiency, reliability and life-cycle cost of the equipment. [0002] Refrigerant cycles are utilized to change the temperature and humidity, or otherwise control the environment, in the conditioned space. In particular, a refrigerant cycle will typically include a compressor delivering a compressed refrigerant to a condenser, and from the condenser to an expansion device. The refrigerant exchanges heat with an outdoor environment at the condenser, and is expanded in the expansion device to a lower pressure and temperature. From the expansion device, the refrigerant continues to an evaporator at which it exchanges heat with an indoor environment, or an environment to be conditioned. From the eva...

AI Technical Summary

Benefits of technology

[0006] In disclosed embodiments of this invention, a refrigerant system incorporates tandem compressors. At least two compressors each separately compress a refrigerant and deliver it into the refrigerant cycle. A reheat coil is also incorporated into the refrigerant system, and receives air having passed over the evaporator to reheat the air to a desired temperature when required. In one embodiment, the reheat coil is positioned in the refrigerant cycle to receive a hot gas. Other embodiments may position the reheat coil such that it utilizes a two-phase mixture of refrigerant, or a liquid refrigerant. Also, some embodiments allow the condenser to be bypassed by at least a portion of refrigerant flow, when desired. Further, the reheat cycle may be incorporated in a system utilizing either economized or conventional tandem compressors, or a combination of both, in other embodiments. Also, in one embodiment, at least one compressor may be unloaded to provide even greater capacity control.

Problems solved by technology

The reheat coil has not been utilized in a combination with tandem compressors, however.

Thus, the refrigerant cycles with tandem compressors have not had as complete control over temperature and humidity levels as may be desired.

Images