I have purchased a Hunter 44760 thermostat to replace my Bard mechanical thermostat (Honeywell LR1620). The Hunter thermostat has the following connections - R, Y1, W2, E, O, B, G, L, C. The Bard has the following connections - R, Y, W2, E, B, G, L, X1 - X2 (jumped together), and W3 (no wire to the o connection). I think the wiring from the old thermostat to the new should go R to R, Y to Y1, W2 to W2, E to E, B to B, G to G, L to L and C to X1. Where would the W3 from the old thermostat go? Tape it off? Put it together with the W2 wire? Thermostat not compatible? Thanks for your help.
Nick

This is a bad honeywell number (Honeywell LR1620). Now I think if you wire it up wrong you may cause some system damage. Are you willing to take the risk? I think you will be better served by having a professional on site fix this problem. The worst thing in the world happened when K-Mart and others started to sell digital/standard t-stats. The box says how easy it is and that is not the case.

I have purchased a Hunter 44760 thermostat to replace my Bard mechanical thermostat (Honeywell LR1620). The Hunter thermostat has the following connections - R, Y1, W2, E, O, B, G, L, C. The Bard has the following connections - R, Y, W2, E, B, G, L, X1 - X2 (jumped together), and W3 (no wire to the o connection). I think the wiring from the old thermostat to the new should go R to R, Y to Y1, W2 to W2, E to E, B to B, G to G, L to L and C to X1. Where would the W3 from the old thermostat go? Tape it off? Put it together with the W2 wire? Thermostat not compatible? Thanks for your help.
Nick
The Honeywell is a Bard branded T874R 1129.

W3 is for a secondary auxilery heat relay. Your wiring looks up to snuff so far with the exception of W3. If it was used on your old system it might have been used to turn on the 3rd stage of heat. Usually this thermostat will control a heat pump and two strip heat circuits separately.

Look here for a diagram paying attention to your subbace part number,

http://customer.honeywell.com/Techlit/Pdf/69-0000s/69-0392.pdf