How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Phil Your Own Question
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
23932409
Type Your HVAC Question Here...
Phil is online now
A new question is answered every 9 seconds

Rudd furnace about 23 years old burners are not lighting.

Customer Question

Rudd furnace about 23 years old burners are not lighting. The main fan is on, pilot is on exhaust fan is not turning on
JA: Did you check the furnace's filters?
Customer: Yes Why would that affect the burner coming on
JA: Do you plan on doing the work yourself?
Customer: Yes
JA: Anything else we should know to help you best?
Customer: I don't think so
Submitted: 2 months ago.
Category: HVAC
Expert:  Rick replied 2 months ago.

Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.

It sounds like you may have an open limit circuit. Do you have a flashing light on the control board? What is the model number of your unit? Model number is ***** the rating tag inside the burner compartment.

Customer: replied 2 months ago.
Ugdg-075auer
Customer: replied 2 months ago.
No lights flashing
Customer: replied 2 months ago.
Also for a few months now the fan continued to run. Other wise the furnace was running normal
Expert:  Rick replied 2 months ago.

Is the fan witch on AUTO? Give me a few to look up specs for your unit

Customer: replied 2 months ago.
On the thermostat? If so no it is on heat
Expert:  Rick replied 2 months ago.

I'm talking about the FAN switch on the thermostat

Customer: replied 2 months ago.
It is on heat
Expert:  Rick replied 2 months ago.

Does your thermostat have a FAN switch? if so it should be on AUTO

Customer: replied 2 months ago.
It is
Expert:  Rick replied 2 months ago.

Ok

Expert:  Rick replied 2 months ago.

Do you have a multi-meter or a continuity tester?

Customer: replied 2 months ago.
Expert:  Rick replied 2 months ago.

Ok, first you can try resetting the rollout switch(es) (see attached pic for typical). They are located just outside the burner chamber. Turn off the power then press the small button between the 2 leads to reset it. If it clicks you have reset it and the unit will fire up when you turn the power back on with any luck. If it doesn't click it wasn't tripped.

Check to be sure there isn't more than one by tracing the leads connected to the switch.

Expert:  Rick replied 2 months ago.

Ok, first you can try resetting the rollout switch(es) (see attached pic for typical). They are located just outside the burner chamber. Turn off the power then press the small button between the 2 leads to reset it. If it clicks you have reset it and the unit will fire up when you turn the power back on with any luck. If it doesn't click it wasn't tripped.

Check to be sure there isn't more than one by tracing the leads connected to the switch.

Customer: replied 2 months ago.
Did not work
Expert:  Rick replied 2 months ago.

Then trace the leads on the rollout to the limit on the front of the unit. It will have 2 wires attached. Turn the power off then jump the leads to the limit then turn the power back on.

Customer: replied 2 months ago.
No
Customer: replied 2 months ago.
Still not working
Expert:  Rick replied 2 months ago.

Is the main lower still running? do you have power to the draft fan?