: We have 2 boilers heating a small office bldg. We're trying to understand how the thermostat for proportionate heating works. I know that 1 thermostat is designed to turn heat on when the outside temp. reaches a certain temperature, but how it the other thermostat supposed to be set. I have set 1 thermostat for the outside temp. say 30 degrees & what shud the inside one be set at???

: Also, can u recommend any books or manuals that we can keep on hand to operate this system.

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