Hi I am new here, I had a honeywell programmable, I replaced it with a RITETEMP programmable. It is working great in the heat mode but, I switched it to cool and the blower won't come on though the unit outside is working and evap is almost iced over. The blower works in heat and in the on position. I have a four wire, red-RH white_W yellow_Y green_G This is how it is connected to stat. Any Ideas out there?

I'm not sure why anyone would replace a Honeywell with a Ritetemp... either the thermostat is not compatible with your system, or the installation/setup is incorrect. Post a list of the terminal connections on the new thermostat.

Also, please give some indication as to what type of system you have. Is it gas? A heat pump?