Plumbing problems - bath and dishwasher
There is usually a shutoff valve somewhere along the line from your hot water heater and usually at the base of each appliance or fixture. I would first make sure the values near the bath and dishwasher are both on. If not try tracking the lines from your hotwater heater to see if any values are shut off.

The values near the bath may look like this: 



The values along the line look like this: