My Nordyne heater blower always running but won't heat?

Question

My 20 years old Nordyne heater is suddenly not heating anymore while the blower is still running. I tried to shut off step by step:
- Turn off thermal switch in mobile home.
- Turn off control valve on heater
- Turn off gas valve on heater
Then I turn on:
- Control valve
- Gas valve
and turn Thermal switch to 70 temperatur grade, but the blower is running right away (normally it blows 30 seconds after thermal switch is turn on) and won't heat.
Could any expert can help me?

Thanks for your help.
Kevin

Answer 1

20 year old heater need replacing with a more efficient heater

Answer 2

The problem is the thermocouple, which checks to make sure the pilot is on before opening the main gas valve to the burner. It's a pretty cheap part, and fairly easy to replace if you're handy. If not, call an hvac person to replace it for you.