The ITT thermostat does not have any letter to indicate where the cables go. The new Honeywell thermostat has R W. From the wall I have 2 cables coming out white and red. What letter goes to what color cable? Help please!

Lets see if we can figure this out. Without an algorithm to guide us, we have 2 wires. Red & White and 2 terminals R&W. Where do you suppose they might go? Red-R, White-W would be logical. This is a heat only system, correct?