Air Conditioning - Upgraded Thermostat Issues

I ordered a couple of new White-Rodgers thermostats from a local HVAC company to replace the non-programmable units that are currently installed.

This is for my parents retail store, which has two AC/Gas Heat Carrier rooftop units and individual Carrier thermostats....very simple digital boxes.

I'm dealing with 5 wires, labeled R, Y, G, W and C on the old thermostats. From what I can tell, this is a single transformer setup.

The new thermostats are model 1F90-371 "pro-spec #90s3p". I chose them because they are lockable and the same as what we have at another store.

I left the factory installed jumper from RH to RC, installed the R on RH, then installed Y, G, and W.....however there is no "C" on the terminal strip....so I left that wire disconnected to try it out.

The unit seemed to work alright, both heat and cooling, but the LED on the thermostat was solid yellow the whole time. From what I found online, this may indicate an issue with the low voltage feed to the thermostat. I reconnected the old thermostat after trying the new one.

Is there a place I should be connecting this C (common?) wire?

The layout on the new thermostat is: --MV--W--RH--RC--G--Y--O--B--6


Thanks a bunch for any help, this is getting pretty frustrating.

-derek

The "C" is not connected to anything on this new thermostat.

The yellow LED indicates the system is running. You have nothing to worry about. You've wired this right. You may want to take some time and look at the programming side though, just so you get it the way you want it.