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 Rick Mather Your Own Question
Rick Mather
Rick Mather, HVAC Technician
Category: HVAC
Satisfied Customers: 3634
Experience:  35 years experience, HVAC
Type Your HVAC Question Here...
Rick Mather is online now
A new question is answered every 9 seconds

HI. I have a Lennox furnace that is about 5 years old (I dont

Customer Question

HI. I have a Lennox furnace that is about 5 years old (I don't remember the model number as I'm at work). Anyways, I changed the Hi/Low switches and cleaned the flame sensor because I had a problem with the furnace last week. Everything worked absolutely perfect until this morning. I realized that the furnace was going on. The blower would start but flame is not ignited. It's Christmas Eve and I'm afraid I'll have no heat for the weekend. What can I do? Thanks.
Submitted: 7 years ago.
Category: HVAC
Expert:  Rick Mather replied 7 years ago.
Looks like you hit the easy stuff but please check the little portds that the hoses are connected too they are the items that get clogged and then it does not sense air flow properly
Customer: replied 7 years ago.
I'm at work right now. I have an electrician friend of mine making his way to my house. I'll tell him to try that. But I did blow into the hose before I changed the Hi/Low switch. Is this the hose you're talking about? Also, if that's not the problem, what else can it be? I used to see a bright orange light before the burners ignite and the flames turn a blue. That's what I don't see happening now. This is the problem that started this morning. My major issue is that today's Christmas Eve and I'm trying to get my furnace running before the Lennox parts place closes for 2 days today.
Expert:  Rick Mather replied 7 years ago.
Thats the most common problem and yes thats the hoses from the air flow switches that present the problems
Rick Mather and other HVAC Specialists are ready to help you
Customer: replied 7 years ago.
Thanks, XXXXX XXXXX friend is on his way as we speak. I told him to try it. I will let you know. Please stand by!!
Expert:  Rick Mather replied 7 years ago.
Hope this works for you
Customer: replied 7 years ago.
We tried blowing into it. He bi-passed the hi/Low limit too. It is not igniting at all. He says it could be the ignitor. What do you think?
Expert:  Rick Mather replied 7 years ago.
Thats most likely area to look next
Customer: replied 7 years ago.

Does this model have a glow plug or spark ignition or both? If so, what do you think would be the problem because before this, I would see a bright orange light, then the blue flames...but now no orange light at all. Would you happen to know which one it could be? Thanks again.

Expert:  Rick Mather replied 7 years ago.
If glow pug it would glow and it would tick if spark start
Customer: replied 7 years ago.
So if it doesn't glow or tick it's because the spark ignition isn't working...thus not allowing the glow plug to glow and tick? If this is this case, then you're saying it could be the spark ignition switch?
Expert:  Rick Mather replied 7 years ago.

Glow stick does not make any noise but the spark one does


Related HVAC Questions