I have a Janitrol 18-60 thermostat with 7 wires I want to use a Totaline P310-0210 thermostat will this be compatible.

As long as you have a wiring diagram, and tag your wires before you detach them from the old one you should be fine.

http://www.ntsupply.com/files/products/p374-1100fm_install.pdf

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