At the heart of the electrofusion welding process is the handheld 230 V EF1 electrofusion welder. The robust construction, water and dust-resistant housing, and easy-to-read graphic display of the electrofusion process provides installers with a durable, reliable, and simple means of installation. The handheld EF1 electrofusion welder automatically recognizes a fitting when connected with the welding cable and also checks the ambient temperature using a sensor positioned in the housing and adjusts the energy level to balance with the surrounding environment. It then applies the correct amount of energy necessary to achieve a successful weld. One welder can handle every type of electrofusion welding coupler, fitting, or entry seal and comes complete with welding leads in a lightweight carrying bag.