My Mitsubishi water cooler is leaking. (The type that holds an upside down 20 liter water bottle)

It is now 3 years old, and sprung a leak somewhere inside where i cannot access it.

Any suggestions for a repairshop that deals with such things?

Try a small workshop on the main street in BangSaray.

Driving from Sukhumvit towards the beach, past the roundabout and almost to the end of the straight piece of road, its on the left (about 50 yards before the sharp left bend).

Just one of those small open-fronted places with bits of TV's and things all over the shop, so you need to look hard to find it. They fix just about anything.