expansion tank and back flow

I have this set up in my basement in a NYC condo for 10 years, I am now being told that this is a problem any thoughts on why there would be two check valves in this set up. Is it a problem . Arrows who direction of flow through check valves/back flow preventers. Supply is Cold water supply

fyi at bottom of photo is a weil mcclain indirect water heater

Do you think the lower check valve should be removed?

Assuming that expansion tank is for the potable hot water expansion...there's not supposed to be any valve of any sort between it and the cold inlet to the WH, so yes, if there's a check valve there, assuming it's working, the expansion tank is isolated, and not doing its job. An expansion tank absorbs the increased water volume when you heat water in the tank...there has to be an unobstructed path to the tank.