The district museum of Samphanthawong district, which basically is Chinatown, was originally located within Wat Traimit, the famous golden Buddha temple. It was however removed there in 2006 in order to make space for the massive rebuilding of Wat Traimit, which now has been fully opened. Within the temple it now has a new local museum on the history of Chinatown, the Yaowarat Heritage Centre, a museum I will try to visit in my next trip to Thailand.
The original district museum was however not completely abandoned, it was moved into the Pathum Kongka temple school, only one block away from its original location. To visit it, one however really has to know where to search, as there is no sign at the school entrance nor at the school building which houses the museum. When I went there, the school entrance was blocked by a goal net, as the students played soccer in the inner courtyard, so I had to ask me way through. I was guided to the office building to the right, the upper floor now houses the museum.
Given the much bigger, more elaborate and better located new museum, and even more the total lack of promotion by the Bangkok tourist office (who told Eric from the Tour Bangkok Legacies website that the museum is still in Wat Traimit even after he noticed it being gone) as well as the total lack of signs towards to museum, I doubt it will attract any reasonable number of visitors except those who were able to find the sparse information on it. Though the Song Wat road, at which the museum is located, has far less tourists walking by than on Yaowarat road, one or two English sign would increase the visitor numbers already a lot.