Making an assessment off all the monastic structures, in the zone demarcated by Chikun Rd, Pa Thon Rd, Pridi Banomyong Rd and U-thong Rd is rather difficult, as the position and name of the structures varies on different maps. On a 19th century map there are 15 structures counted, while on the 20th century Phraya Boran Rachathanin map there are 13 mentioned. There is inconsistence in the names and the positions. Even a map drafted in the 90's by the Fine Arts Department, what I presume, based on excavations in the zone, shed no light on this matter. Positions of monastic structures can be asserted, but their ancient names will remain questioned forever.
The monastery is mentioned in the Royal Chronicles of Ayutthaya during the reign of King Borommakot (r.1733-1758). Prince Suren Phithak became ill and ordained at Wat Khok Saeng. Sena Phithak the son of the elder consort of the king and two of his children laid an ambush for Suren, for a unknown reason. Suren escaped Sena Phithak's attack and reported afterwards to the king. The elder consort, realizing her son was in danger, smuggled Sena out of the palace in her palanquin and took him to Wat Khok Saeng, where he was ordained. King Borommakot searching for Sena and unable to find him, ordered the execution of the latter's two children. 
 The Royal Chronicles of Ayutthaya - Richard D. Cushman (2006) - page 428-430 / Source: Phan Canthanumat, British Museum, Reverend Phonnarat & Royal Autograph - Illness of the Prince-Monk, 1735.
When it was the seventh month of the year of the hare, seventh of the decade, the Holy Lord Omnipotent became ill with a holy disease. His Majesty the Department of the Fourth Rank Suren Phithak came in to stay at the Monastery of the Knoll of Light and regularly came in to [C: pay visits to] [D: visit with] the Holy Lord Omnipotent. One day, in the evening, the Holy Lord Child and Department of the Fourth Rank Sena Phithak sent His Holiness Chün and His Holiness Thet, His sons, out to [C: invite] [D: extend an invitation to] His Majesty the Department of the Fourth Rank Suren Phithak [C: at the monastery], by saying, “A holy royal proclamation has been issued to have Your Majesty invited to go [to the King].” His Majesty the Department of the Fourth Rank Suren Phithak, assuming that it was true, came and ascended in front of the Holy Victory and, advancing, reached [D: the center of] the doorway where the Department of the Fourth Rank Sena Phithak was hiding behind the doorway. He slashed at Him with His holy sword weapon and tore His waist cloth and cold weather robe, but failed to cut into Him. The Department of the Fourth Rank Sena Phithak ran on in to [C: a place in] the interior. CD: His Majesty the Department of the Fourth Rank Suren Phithak entered the place where the Holy Lord Omnipotent was [lying] ill. Looking with His holy eyes and seeing Him, the King asked, “How come the cloth of Your cold weather robe and of Your waist cloth is torn?” The Department of the Fourth Rank Suren Phithak bestowed His holy blessing and said, “The Department of the Fourth Rank Sena Phithak was playing a joke.” When the Department of the Fourth Rank Suren Phithak bestowed His holy blessing [C: and] [D: ,] took His leave [D: and came forth], Her Majesty the Department of the Third Rank Aphainuchit, the Holy Mother of the Department of the Fourth Rank Sena Phithak, followed after Him and pleaded with Him, saying, “If father doesn’t help, it appears His younger sibling will die.” The Department of the Fourth Rank Suren Phithak [C: asserted] [D: said], “Only the Lumnitzera dyed cloth, which is the victory banner of the Holy Arahats, will accordingly be able to help Him.” The Department of the Third Rank Aphainuchit having regained Her [C: holy] senses, Her Majesty thereupon went in to ride Her holy canopied palanquin, hid the Department of the Fourth Rank Sena Phithak [inside], took Him out by way of the Gate of the Covered Passageway and had Him take His [C: holy] vows [as a monk] at the Monastery of the Knoll of Light and stay with [C: the] [D: that] Department of the Fourth Rank Suren Phithak. The Holy Lord Omnipotent had [C: people search for] His person [D: searched for] but [C: they did not find Him] [D: He was not found]. Finding only His Holiness Thet and His Holiness Chün, [the King] accordingly had Them [C: sprinkled] [D: executed] with sections of sandalwood. [The Royal Chronicles of Ayutthaya - Richard D. Cushman (2006) - page 428-430 / Source: British Museum & Reverend Phonnarat.]
Text & map by Tricky Vandenberg - November 2010 Reviewed May 2012