This guide on Rheem RTEX-18 Troubleshooting will break down:  Note: This is an electric tankless water heater. If you have a gas unit, read this article on the Rheem Tankless Water Heater Troubleshooting Manual. Rheem Rtex-18 Troubleshooting: Common Problems & Solutions Here are the common problems you might experience:  1. Water Heater Isn’t Heating At … Continue reading Rheem Rtex-18 Troubleshooting [Complete Guide]