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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22678
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Model # is M7RL Series there is no hot air but the furnance

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model # is M7RL Series there is no hot air but the furnance blows cold air the service light are all off except for the green and it flashes
JA: Did you double-check the thermostat's settings? And what about the filters?
Customer: Filter is new and the thermostat setting is OK
JA: Do you plan on doing the work yourself?
Customer: not sure if is a limit switch on the outside then probably, If not the Furnace is less that a year old so I will probably have it fixed under warranty. I don" know who I can callt
JA: Anything else we should know to help you best?
Customer: I don"t think so I do live in ST Charles ID


My name is Billy.

So the red and yellow are not lit...just the green continuous blink?

Customer: replied 27 days ago.

I see you mentioned limit switch so you already are on the right track...

Just above the burners on the front wall is the limit we want to you know where this is? Or can you post a pic so I can draw part location for you?

Customer: replied 27 days ago.
It looks like there are two a main limit switch above the burners and one above that on the Combustion air pipe.

correct..they are different circuits but could still code the same.

Now..the one on vent there a tiny button in center? and the one on front wall is credit card sized?

Customer: replied 27 days ago.
There is a bottom on the vent pipe a do not see any thing on the other

press button on vent switch...then tap the other limit above burner 3-4 times....tell me if light pattern changes

Customer: replied 27 days ago.
The furnace lite and all light are on. Does this mean I have one of the switch that are bad?

Either bad...or reacted to a problem.

Can you try a heat cycle now?

Is the furnace running now?

Customer: replied 27 days ago.
It has cycled and it worked.i let do a complete cycle.

Excellent news....this could have been previous due to a dirty filter....obstruction in pipe now gone..anything that caused a bit more heat than normal.

I am glad all is well for you now...I would hold calling for service and only call if it were to trip again.

Just rate service (5 star rating system) to close for now and move off the active list.

Thank you!


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