need help hooking up a classic 3 to a regular 2 wire Honeywell round thermostat

[SurClay]

Im going to start here.
I have a round honeywell thermostat (3 wire input R, Y, W ) , on the classic 3 there is a th/tp, tp and th.
I ran the th/tp wire (white ) to the W on the thermostat and the TH wire (red) to the R wire on the thermostat and I get nothing, But when I connect the two the together they work. Would this mean my Milavolts are to little?

Any advice would be so helpful Im pulling my hair out , it's been days lol

 

[DAKSY]

What ARE the millivolts being generated by the thermopile? Are you sure you have a millivolt thermostat?

 

[Lennox65]

Im going to start here.
I have a round honeywell thermostat (3 wire input R, Y, W ) , on the classic 3 there is a th/tp, tp and th.
I ran the th/tp wire (white ) to the W on the thermostat and the TH wire (red) to the R wire on the thermostat and I get nothing, But when I connect the two the together they work. Would this mean my Milavolts are to little?

Any advice would be so helpful Im pulling my hair out , it's been days lol

If you mean that the Red and White wires are connected to the respective TH and TH/TP terminals on the valve, then just touch them in different combinations of R,,W, and Y on the thermostat while the thermostat is set high enough to call for heat to find out which two terminals on the thermostat call for heat.