Low shower pressure when another faucet turned on
Recently I installed a second hot water at the MBR and kitchen end of my long rancher. (Formerly, it took a LONG time for HW to reach the Master Bath and Kitchen; the new HW heater remedied that.) Howe ver, now when the shower is in use and someone runs hot or cold water in the kitchen or Master Bath sink, the water termperature in the shower changes drastically. Before I installed the new HW heater this occurred only very slightly. Now it is quite pronounced, making for a very uncomfortable shower (usually accompanied by a scream.) I've checked all the valves and they are all wide open. Any suggestions?