I recently bought an older home with a gas fired boiler, picked up a Hunter Digital Thermostat(model 44155c) in order to change out the old one(White-Rodgers type 1f35-910). On the old termo plate, there are 3 wires: a red that was near a Y6 marking, white by R5 and a yellow/tan near a 4 marking. The new thermostat has RH, RC, Y/O, W/B, G and Y1. Which ones go where? The wiring directions really aren't that clear to me, so I followed the wires into the basement and they are connected to a White-Rodgers Zone-a-flow water valve(model 1311-102). Have been researching and struggling with this for hours now. I'd appreciate any and all suggestions. Thank you.

Oh, I forgot to mention that I have 2 thermostats to control the heat in the house. I think 1 controls most of the first floor and addition, and the one in question, controls one room on the first floor and the 2nd and 3rd floors.

Similar question. Three wires running from the Honeywell Intermittent Ignition Oil Primary (model R8184 G 1427) black, red, and yellow. Where do they fit into the Honeywell thermostat (model RTH2310). The thermostat has connectors marked Rh and Rc with a jumper between them, W, Y, and G. The wires are connected to the ignition primary with the black and red connected to one contact and the yellow connected to the adjacent contact.

On a side note, why don't the thermostat manufacturers define the function of each connection and it's associated letter? They like to state that one should mark the wires before removing them from the previous thermostat, but what is one to do if the thermostat was removed by another person who ignored step 1?