vkiNm, I would just like to say that running water wouldn't be too much of a surprise to people with medieval-era tech, or even 0BC/AD level tech. They had running water in ancient Roman times. Granted, the pipes weren't the best for your health, but still.
Historically the European middle age peoples would have been awed. The Romans took running water indoors, fish fountains with nozzles squishing jets of water, and massive aqueducts with them wherever they went. When they fell to barbarian tribes, the knowledge wasn't all lost but fell out of use with the odd architecture manual stuffed in someone's library.
With barbarians pulling down aqueducts to besiege towns all over the place and whatnot, and settling under the shadow of the wisdom of the ancients, they were awed enough for the Christian church to take easy hold (having the ancient Roman title of Pontifex Maximus was for them the same as saying that the church was the inheritor of the ancients' wisdom and power).
Enter the church spreading their religion, declaring the Frankish unwashed barbarians as the political successor of the Western Roman Empire and enforcing conformity - but said conformity according to the New Rome barbarian overlords' mores, lest they found the Papacy too much trouble.
Result: the dung ages, a massive inferiority complex to the ancients, and scholastics.
So yes, running water would have been huge for medieval Europe; what few cities that retained aqueducts were considered awesome just because people could take water from public fountains built on walls and statues - evidence that they were closer to the ancients' wisdom.
Running water indoors, and heated water? Unthinkable