Installing 5-2 progrmmable Honeywell thermostat

[kumarp5]

My HVAC system has a C wire and so does my old Honeywell non programmable digitial thermostat. In order to save some money I bought a Programmable 5-2 day programmable thermostat (Honeywell). This thermostat does not have a position for the C wire (The other positions are Rh, Rc(connected by jumper to Rh), W, Y, G and it matches with the new one)

The question is - can I leave the C wire unconnected?

If yes, what are the pitfalls of doing so

Thanks

[RBM]

The thermostat doesn't use a common. No pitfalls

[mm]

I learned that if you don't connect the C wire, it will detonate, usually in 10 hours.

I learned this watching "24".