My blower is on and no heat comes out of the furnace the troubleshoot says the limit switch needs to reset I reset the limit switch heat comes on for 5 minutes then trips again what do I do? Heil furnace

You have poor air flow for some reason. The blower could be dirty, or if you have AC coils on top of unit they could be stopped up with dirt. If the coils are stopped up they have to be removed and pressure washed after the application of coil cleaner. The blower gets stopped up with dirt which can be cleaned by sliding out blower and cleaning with soap and water while keeping motor dry. It's best to remove blower wheel and cleaning it and then re-assembling.