This paper demonstrates some results from an on-going experiment on energy management in a residential testbed in Singapore by controlling the air-conditioning (AC) system. The testbed is set up at the faculty housing of Singapore University of Technology and Design (SUTD) in which the ACs installed within each unit can be controlled from a remote server. The control can be conducted both in terms of switching on/off and changing the temperature set-point of the ACs. The main objectives are to reduce the consumption of energy at a residential setting by controlling the ACs' temperature set-points and investigating the feasibility of having residential ACs as interruptible loads for demand response and thus enabling residential users to participate in the energy market. The control methodology is briefly discussed and the users' inputs on the experience of such experiments are also explained. Some preliminary results from the experiments are discussed and some insights are provided into how much load can be controlled through the set-point temperature of ACs such that the users do not feel any discomfort.