3400-820 low duct temp

[WoodyUSSLUCE]

My Coleman 3400-820 heater was producing less heat today than normal. I checked it with a thermometer at the floor duct and it was showing 92 degrees with an actual room temp of 70 degrees. The blower motor works fine and if I lower the thermostat setting the system will cycle like normal. I suspect that 1 or more of the coils may have gone open. If that is the case which restring kit will I need to order ?

[WoodyUSSLUCE]

I fixed it today so I wanted to post in case anyone else had a similar problem. I found a loose wire going from 1 of the main wires coming off the fuses to the sequencer. I replaced the terminal and the temp went up 10 degrees. I kept checking and found the ductwork that connects the other side of the home to the furnace leaking and sealed that for another 10 degree boost. While I was checking the wiring I checked the resistance of all the heating coils and they were all less than a 5 ohm difference in resistance so they seem to be in good shape. All coils are getting the right voltage and the thermoswitches test good. I've been running the system for a few hours and it seems to be working normal.