General topics about all things heating, ventilation, air conditioning and refrigeration.
3 posts • Page 1 of 1
I have an older gas furnace (Trane 1989 vintage) that does not have any fusing for the low voltage control board. Older boards were not as processor/IC oriented long ago. But today most all have a fuse to protect the control board. However what they do not usually have is any protection for induced current spikes from lightning on the thermostat/control wiring.