02-658 C.M.R. ch. 9, § 19 - Thermostatically-Controlled, Hand-Fired Warm Air Units
A 250 degree Fahrenheit limit control must be installed in the supply plenum not more than 10" above the top surface of the heat exchange and must extend at least 12" into the supply plenum.
The limit control must automatically prevent operation of the furnace in the event of power failure or shut off when 250 degrees Fahrenheit temperature is reached whether or not the electrical power source is available.
A barometric draft control, if required, must be installed in accordance with the manufacturer's instructions.
Notes
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