Dear Ms. Dunn,
Thank you for posting your request on History Hub!
We searched online and located a photograph of Coit House on the website of the Ohrstrom Library Digital Archives, along with an article about the history of the orphanage. Because the orphanage was linked with St. Paul’s School, Concord, NH, the school’s Ohstrom Library may be able to assist you with locating records. We also located records listed in the catalog of the New Hampshire Historical Society. Since Coit House was affiliated with the Episcopal Church’s Diocese of New Hampshire, the Archives of the Episcopal Church and The Archives of the Episcopal Diocese of New Hampshire may have relevant records and you may wish to contact the Concord Historical Society and the New Hampshire State Library.
We searched WorldCat and located several listings. We also searched HathiTrust and located the book Historical Sketch of Coit House, formerly the Orphans' Home of Concord, N.H., which has been digitized in full and can be viewed online. Finally, we searched Google Books and located Memorials of St. Paul’s School which includes some information about the beginning of the Orphanage near the school. See pages 54-57, 113.
Residents of orphanages as of the enumeration date are also listed in the federal decennial census. For more information about using census records, please see our topic page on Census Records. If there is a specific census year or individual you are interested in, please post a follow up here on History Hub and we can assist you.
We hope this information is helpful. Best of luck with your research!