York Thermostat Replaced Thermostat Furnace Doesn't Go No With New T-stat. Why?

Replaced thermostat furnace doesn't go no with new t-stat. why? - york thermostat

By replacing a manual thermostat with Honeywell 7400D York. I put the cables in exactly the manner in which they were old (G to G (, Y, Y, and W for W and R with R, which is to be filled)). All operating systems, except heat in the oven not at the start (even after 5 minutes) increase in temperature. Can not understand why. How can I get it to work?