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Coleman 3400A Wire Diagram / Parts manual/ Helpful user guide (Download)
Parts list for the 3400A812 Coleman electric furnaces. 10.6KW or 36,000 BTU.
The Coleman 3400 and 3400A series are mostly identical. Unlike many newer Coleman furnaces, the Coleman 3400A series was not built to be air-conditioner ready. To make the furnace A/C ready, an A/C control box and upgraded blower assembly were usually added. 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.