A novel control algorithm, named H-L control, for a direct expansion air conditioning system was previously developed, so that an improved indoor humidity control was achieved at a higher energy efficiency. However, a variable speed compressor was used, leading to a high cost of implementation for the control algorithm. This technical note reports on an experimental study, where two parallel connected single speed compressors were used to replace an expensive variable speed compressor to implement the novel control algorithm. Experimental results demonstrated that similar control performance may be achieved when using two single speed compressors, thus lowering the cost of implementation.
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