Polymer components offer a lightweight, low cost option for heat exchangers and absorbers as well as storage vessels.  These components must be designed to consider heat transfer performance, mechanical (strength) performance and lifetime.  Polymer degradation in hot potable water may be delayed through the use of certain antioxidants.  In the present study, data are presented which show that antioxidant depletion in polyethylene (with a phenolic additive) is accelerated in hot potable water.  Characteristic time scales for antioxidant depletion are evaluated for this polymer/antioxidant combination at 80°C.  These time scales indicate that the rate of antioxidant depletion is controlled by chlorine diffusion into the polymer (and subsequent reaction between the chlorine and antioxidant).