Wehat Chamrun is a Chinese-style two-story mansion at Bang Pa In Palace that was built by the equivalent of the Chinese Chamber of Commerce and presented to King Chulalongkorn in 1889. Prince Ookhtomsky recorded that,
” It is really a palace of romance, with ornamented tiled floors, massive ebony furniture, gold, silver, and porcelain freely used for decorative purposes, and delicate fretwork on the columns and on the windows. Evidently we have before us the principal sight of Bang Pa-In. The Emperor of China himself can scarcely have a palace much finer than this”
The ground floor contains a Chinese-style throne; the upper story houses an altar enshrining the name plates of King Mongkut and King Chulalongkorn with their respective queens. This Chinese-style mansion was the favourite residence of King Vajiravudh (1910-1925) when he visited Bang Pa-In Palace. 
Unfortunately no photos are allowed inside the second story where many fine decorations, exotic sculptures and old Chinese furnishings reside.
 Encyclopedia Thai – Phra Thinang Wehat Chamrun – http://www.encyclopediathai.org/sunthai/center/ayut/bagin13.htm Accessed 19 Sept 2015