I installed a hot water recirculating line & pump to my kitchen sink/faucet when I finished my basement. I was supposed to add a check valve at the water heater inlet(to keep recirculating water flowing in the right direction). I was concerned about flow restriction from a check valve so I never installed one. Now I'm realizing I need one because I get warm water in my cold water lines from time to time.
Anyway... I need to install one but I'm still concerned about flow restriction. My water heater is all 3/4" fittings/lines. Right now it wouldn't be any harder to go to a 1" check valve if that was better. Will a 1" check valve perform better? Am I overthinking this?