Modine Hot Dawg heater - no heat

That sounds like the limit look for a little round thing with two wires with a button between the wires push it to reset it but there could be several of them even one buy the blower motor there is also a high limit in the center of the furnace all you see is two wires if that one is out you have to remove it two screws then just drop it on the floor it will free the numeral bymetal inside put it back on and you should begood