That's some pretty nasty direct afternoon sun. Some of my heucheras will tolerate some sun, but none like a lot of direct sun. Treat them like ferns or hostas. Keep them moist and they may recover in the fall. Heucheras are also very tough.

Too much sun. Some of my heucheras get sun from 11 til 1, and that's almost too much for them. They have shade and filtered light the rest of the day. The ones that do best for me are planted at the edge of a woodland garden where they get filtered light all day long - in other words they get lots of light, but they are never in direct sun. I'd try cutting off the crisp leaves and moving them to more shade. They probably won't look too good the rest of this summer, but should come back ok next year or over the winter.

Thanks all. This weekend I made a new bed and moved them into more shade. they get some morning sun until about 1 then are in bright light but no sun.