no hot water at some fixtures

[dbower]

I'm in a 20-year-old house. Never had any particular hot water problems. Gas water heater. Today, some fixtures (dishwasher, kitchen sink, etc) suddenly provide only cold water from both hot and cold valves. Other fixtures (bathroom, etc) provide plenty of hot water as always. I'm stumped.

[Plumbguy]

I'm guessing their is a restriction somewhere in the system. what type of material is your home water piped with? Copper, galvanized,cpvc, etc..
a restriction will cause the water to mix longer than it should causing the hot water to take forever to reach effected area. have you checked the aerator on the KS. The dishwasher has a screen where the water line connects to the solenoid underneath.