How do you fix a 3107541.009 analog thermostat that will not regulate heat or cold?

Sounds as if the thermostat is not regulating heat effectively. It may need to be replaced

Do have AC? if you do you have to by a thermostat that can handle both heating and cooling, if you only have 3 terminals it must be a heat only thermostat.

"HOLD" is to override any schedule in the controller and HOLD the current setting.

here is the guide. http://www.repairclinic.com/RepairHelp/How-To-Fix-A-Dryer/8-200-865067-/LG-Dryer-doesn-t-heat-DLEX3360V

Could be the heater core went bad, heather core lines are plugged, cover on the blower motor is off, or if your temp selector is cable, the cable may have seized

Sounds like you have a stuck thermostat. New or not, thermostats can get stuck.

It should be 200 degrees. If your running cold the only thing that regulates temp is the thermostat. If it is indeed 150 degrees thats why you have no heat.

If you replaced the water pump and the radiator for this condition then it was a waste of money. If you had a water pump or radiator problem it would overheat.

The fact that your blowing cold air tells me the that you really are 150 degrees or the heater core is plugged.

sounds like the thermostat has a problem and needs to be replaced. The thermostat regulates temp and it defective can either stay closed or stay open and I reckon in your case it has stuck open permanently.
Your manual should show you where the thermostat is located.

go to myhome.honeywell.com and search for a manual for your model number thermostat on the right hand side of the page

sounds like it is miswired. actually try fan on with the heat on and see if the fan works.

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