I am having a devel of a time finding a replacement thermostats for my Hydronic system.

I have tried a couple and they do not wire up correctly, even though they say for "Hot Water systems" they are for 2 wire and I have a 3 wire system.

OK, I have a Lochinvar Knight high efficiency boiler with 6 zone valves.
The zone valves are: White-Rodgers Type 1311-102

I want to replace my old murcury thermostat with non programmable digital ones.

The zones take three wires:
4 and 6 to open valves
5 and 6 to close valves.

Don't need anything fancy - just something simple and hopefully not expensive and something I coule get at the big box store.

Thanks
George M

1311 COMPATIBLE THERMOSTATS TABLE These are all White Rodgers thermostats.

Model Number Programming Options Contacts Profile Terminals
1E35-910 Non-Programmable Sealed Mercury Cell Vertical 4, 5, 6
1F35-910 Non-Programmable Sealed Mercury Cell Horizontal 4, R5, Y6
1F90-371 5+1+1, 5+2 Electronic Horizontal RC, RH, W, Y, G, MV, O, B, +, S, -, 6
1F96-344 Non-Programmable Electronic Horizontal RC, RH, W, Y, G, MV, O, B, +, S, -, 6
1F97-371 7-Day Electronic Horizontal RC, RH, W, Y, G, MV, O, B, +, S, -, 6
1F95-1277 Touch Screen 7-Day, 5+1+1, or Non-Programmable Electronic Horizontal RC, RH, C, W/E, W2, Y, Y2, G, O, B, 6, L, +, S, -
1F97-1277 Touch Screen 7-Day, 5+1+1, or Non-Programmable Electronic Horizontal RC, RH, C, W, Y, G, O, B, W/E, L, 6, +, S, -
1F97-391 7-Day Electronic Horizontal RC, RH, W, Y, G, 6, HM1, HM2, S1, S2, S3
1F80-0471 5+1+1, 5+2, or Non-Programmable Electronic Horizontal RC, RH, C, W, Y, G, O/B
1F86-0471 Non-Programmable Electronic Horizontal RC, RH, C, W, Y, O/B

Are you set on digital. Or would you be happy with any thermostat without mercury. Honeywell makes a great heat only (looks almost exactly like the old t87) themostat.

Thanks,

I'll look into these.

George M