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Tom
Tom, HVAC Technician
Category: HVAC
Satisfied Customers: 770
Experience:  16+yrs HVAC/R service. Residential Commerical Industrial
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furnace will not stay lit comes on then goes off after a 20

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furnace will not stay lit comes on then goes off after a 20 seconds

Tom :

Hi, sorry you're having furnace problems...

Tom :

Did you try cleaning the flame sensor?

JACUSTOMER-dl2cklck- :

No how should I do that?

Tom :

If you look at the burners in the furnace..the flame sensor mounted in front of the furthest left burner on the bottom of the burner box...

Tom :

It will have a single insulated wire attached....usually one screw to remove it then clean the probe with some fine sand paper or steel wool. The alternating lights are a pretty good indication that the control board is not getting a good flame signal.

Tom :

Would you like me to link you to a manual for your furnace?

JACUSTOMER-dl2cklck- :

No, I have the manual in front of me. I am reviewing it now

Tom :

Page 15 shows the flame sensor.

JACUSTOMER-dl2cklck- :

Please send the manual

JACUSTOMER-dl2cklck- :

Would it be a green insulated wire on the front connected with a hex screw?

Tom :

No...

Tom :

One second I'll link the manual..

JACUSTOMER-dl2cklck- :

found the wire cleaning it

Tom :

OK! Good job...I hope this takes care of it for you.

JACUSTOMER-dl2cklck- :

fired it back up and it is still sputtering after start up and died out

Tom :

You don't have ice conditions where you are do you?

Tom :

freezing rain?

JACUSTOMER-dl2cklck- :

Well, how about 2' of snow? We live in MN

Tom :

Yikes!

Tom :

Does the flame look 'weak' to you?

JACUSTOMER-dl2cklck- :

This happens every year. Technicians in past have had to clean dust out of hoses and then replace the pressure switches

Tom :

I don't think it's a pressure switch.....

Tom :

If it was it wouldn't try to ignite.

JACUSTOMER-dl2cklck- :

OK...good

Tom :

Are you on natural gas?

JACUSTOMER-dl2cklck- :

yes

JACUSTOMER-dl2cklck- :

flame starts up strong but then flutters out

Tom :

I'm wondering if you gas pressure regulator vent is frozen over....

Tom :

Do you know what the regulator looks like?

JACUSTOMER-dl2cklck- :

ummm, remind me please

Tom :

ok...hold on one sec....

JACUSTOMER-dl2cklck- :

let me put on the boots and go check

Tom :

If you look at your meter...there should be a regulator like the one in the pic...see arrow..

Tom :

The vent is the round part pointing down with a screen in it...it has to be open

Tom :

Ok...no problem..

JACUSTOMER-dl2cklck- :

Wow...thought that was it. Regulator was buried by snow. I cleared it out, restarted the unit and it sounded real good. Flame was stronger, but didn't last. Blower came on twice, but flame sputtered out after 50 secs or so.

Tom :

Did you make sure the screen was open?

JACUSTOMER-dl2cklck- :

let me check again...I'm sure that's it...stand-by

Tom :

no problem

JACUSTOMER-dl2cklck- :

Well, we think that was it! Best $23 we've spent in a long time. Thanks Tom. Please remind any other emailers from MN to check the regulator as we have had record snow in the last 24 hours!! Thanks again.

Tom :

No problem..the furnace is running??

JACUSTOMER-dl2cklck- :

Yes!!

Tom :

Ok.....glad to hear it...

JACUSTOMER-dl2cklck- :

Been on for 10 mins now

Tom :

I live in Iowa...I've seen it a few times..

JACUSTOMER-dl2cklck- :

I'm sure you have. Thanks again

Tom :

Ok..!! You did all the work...

Tom :

Feedback appreciated after you accept....it helps my expert rating..!


 

Tom :

Anything else I can do for you?

JACUSTOMER-dl2cklck- :

I had to take shovel and dig from an 8' snow drift on side of house

Tom :

!!!!

Tom :

So far we have about an inch...I hope it stays that way!

JACUSTOMER-dl2cklck- :

I'll accept and definitely send positive feedback

Tom :

No wonder it took you awhile!

Tom :

Ok..stay warm! Tom

Tom :

Thank you1

Tom :

!

JACUSTOMER-dl2cklck- :

Thanks...Go Vikings

Tom :

Anyone but the Bears...

JACUSTOMER-dl2cklck- :

Amen

Tom :

lol!!!

Tom :

Have a good nite.. Tom

JACUSTOMER-dl2cklck- :

You too...

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