circuit board wired outside air handler

[Rod Figueroa]

A friend sent me this photo of a small circuit board (control board?) wired up to thermostat wiring at the attic mounted air handler. Without getting him to take another picture, i was wondering if this is most likely the control board or if it could be something else and whether there is any issue with having it mounted outside the housing. Thank you.

[Markus Keller]

Based on unit color, looks like an older Janitrol. That is not the motherboard or anything else that comes with that furnace. My guess is the motherboard died and they didn't want to spend the money on a new one. That's some guys retrofit.

[Dom D'Agostino]

It doesn't belong there, even if it was intended to replace a failed part internally.

Maybe someone was "part swapping" to find a fix, and didn't finish the job.

Tell him it's worth a few bucks to have pro check it out and repair it.

[Jim Luttrall]

Look for zoned air dampers and dual thermostats. That is likely the innards of the central control.

[Rod Figueroa]

Thank you for the responses. He told me there was only one thermostat (no separate zones).