This study investigates Personalized Environmental Comfort Systems (PECS) as a solution to address individual thermal comfort needs in office environments. Utilizing small Vapor Compression (VC) units to provide cooling has the potential to reduce central HVAC set points, resulting in energy savings. However, the main challenge for VC-based PECS is heat rejection. Outdoor expulsion requires significant building integration constraints, while indoor expulsion may cause discomfort and energy inefficiency. The proposed alternative approach involves storing heat during cooling periods and releasing it during off-peak hours. A compact water-to-water VC unit for desktop PECS applications was developed, tested, and connected to a water/PCM rejection tank. It can store condensation heat produced over 8 h of continuous operation while delivering an average cooling capacity of around 200 W, with COP higher than 2.