R134a is considered as an alternative refrigerant to R22 for air conditioners. An experimental investigation was made to study the characteristics of the heat transfer and pressure drop for R134a flowing in a fin-and-tube heat exchanger used for commercial air-conditioning units. Experiments were carried out under the conditions of inlet refrigerant temperature of $60^{circ}C$ and refrigerant mass fluxes of $150,;200,;and;250;kg/m^{2}s$. The inlet air has dry bulb temperature or $35^{circ}C$, relative humidity of 40% and air velocity varying from 0.68 to 1.6 m/s. Experiments show that air velocity decreased by 5.9% is needed for R134a than that of R22 while pressure drop for R134a was $18.1{sim}20.4%$ higher than that of R22 for the degree of subcooling $5^{circ}C$. The results are useful in designing more compact and effective condensers for various refrigeration and air conditioning systems using refrigerant R134a.