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Parts list for the 3500A818 Coleman electric furnaces. 16.1KW or 55,000 BTU.
Unlike many newer Coleman furnaces, the Coleman 3500A series was not built to be air-conditioner ready. To make the furnace a/c ready, the blower assembly was upgraded to a 3500-6901/A and an a/c control box was added. For 2-wire thermostats, a 3500-5821 a/c control box was added. For 4-wire thermostats, a 3500-5841/B a/c box was added. For heat pumps, a 3500-5871 control box was used. For 4-5 ton air conditioners, a 3500-7901 blower assembly was used. The original 3500-5901 blower assembly is no longer available. If this furnace was paired with an air conditioner of a different brand, the a/c control box and blower assembly may be of that brand. For example, adding a Nordyne air condition was common practice.
Click here to view an installation manual which includes wiring diagrams.