homemade temp controller

I was wondering if anyone could tell me if i could make this work for a fridge temp controller. At work, we use watlow temp controllers wired in with a mercury relay to control heating elements. The temp controllers are controlled by 110 but they are wired in with a mercury relay which has one phase of 575 ran through it(the heating element runs off 575).

 

See if there is a contact rating on the controller. Usually there is a max amperage and voltage listing somewhere. If the contacts are handling 575 volts right now 110 volts for the refrigerator shouldn't be an issue.