I think, these translations would be best:

•chilled water = kaltes/gekühltes Wasser (gekühlt sounds a bit better)

•ambient water
--> there are multiple possible translations:

- **raumtemperiertes** Wasser (this is an **official word** by producers of water dispensers)
- ungekühltes Wasser (like you already said)
- laues Wasser

•hot water = warmes/heisses Wasser

Hope I could help you.