Editing Unity Temple (section)

=== Mechanical features ===
Unity Temple originally had a coal-fired steam boiler, in addition to concrete ducts that were supposed to distribute heat.<ref name="AR-2006-02" /><ref name="Hampton b253" /><ref name="Sokol p. 137">{{harvnb|Sokol|2008|ps=.|page=137 }}</ref> The ducts proved ineffective at carrying air,<ref name="Sokol p. 137" /> and as such, steam radiators were installed shortly after the temple was finished.<ref name="AR-2006-02" /><ref name="Hampton b253" /><ref name="Sokol pp. 138–139" /> A hot-water system was also installed within half a year of the temple's completion; it remained in use through the 21st century.<ref name="Southern Illinoisan 2005" /> The coal-fired boiler was replaced with an oil-fired boiler in the early 20th century, and a gas generator was added later in the century.<ref name="AR-2006-02" /> Since the 2010s, the church has been heated by a [[geothermal heating]] system,<ref>{{cite web |last=Lydersen |first=Kari |date=October 15, 2018 |title=Geothermal and the city: Utilities and industry push installations in Chicago |url=https://energynews.us/2018/10/15/geothermal-and-the-city-utilities-and-industry-push-installations-in-chicago/ |access-date=January 27, 2025 |website=Energy News Network }}</ref> which consists of nine {{Convert|500|ft|4=-deep|adj=mid}} wells on the lawn just north of the church.<ref name="Johnson o698" /> This system includes ice-storage space and a set of geothermal wells.<ref name="Hampton b253" /><ref name="AR-2006-02" />