I need to replace on old Weathtron baystat239a with a Hunter 44260 but the wiring does not match, The weathtron has 8 wires and the Hunter uses 4 wires a green, yellow and a white with a jumper between rc & rh, I don't have a wire for rc & rh. Please help.

Jumper that rc and rh together (or put the jumper back on as it was) unless you're sure you have a dual transformer system (pretty rare). Just so you know that Hunter is designed to control Single Stage Heat Pump - No auxiliary, if that's what we're dealing with here. So I'd need to know more about what were controlling before recommending other wire mappings, or know if you have the wrong thermostat.

The olw Weathertron has an auxiliary, do I need it?

You might, what are we dealing with here? A furnace and straight A/C? Heat pump with Aux backup where aux is a furnace or heat strips?

Heat pump with aux wth heat strips

As mentioned that Hunter will not support what you have, as it says in the Owners Manual. Time to get your money back.

Thank you for your help

Please recommed a thermostat that will work

I would pick Honeywell for the sheer volume of support from Honeywell and out on the net with folks familiar. A number of their models will work for your application depending on the bells and whistles you like. Just be sure to read the manual to verify it will work for you. Repost if you have one selected but are not sure.

I have found a Honeywell yrth31001029, please advice.

Unfamiliar with that model. Is that the correct model number?