I vetwo bathrooms server served by the same hot water tank from the attic. The master bed room bathroom doesn't get hot water in the sink or shower. Any clues ?

1. Is this a storage-type water heater or instant?
2. When did this start? Has it been gradual or sudden?
3. Do you ever get any hot or lukewarm water in the master bath?
4. Have you made any plumbing changes?
5. Do you know if there is a thermostatic mixing valve or other tempering device on the plumbing?
6. Are you having any other plumbing issues, e.g. broken or leaking shower/tub valves, faucets, etc.?
7. Are you getting any water at all through the hot taps? If so, is it the same pressure that you had when it was hot or before the problem started?
8. Do you happen to know how the pipes are routed to the master bath fixtures? Do they run through an outside wall? Through an uninsulated attic space?