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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22514
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Blinking RED light on American Standard Freedom 80 Comfort R furnace

Customer Question

I have an American Standard Freedom 80 Comfort R furnace. Red light is blinking on the front. I know this is something simple... Can't find ANY manuals or trouble-shooting guides online. Can anyone help Please?

Optional Information:
Make : American Standard
Model : Freedom 80 Comfort R

Already Tried:
Cleaning filter.

Submitted: 6 years ago.
Category: HVAC
Expert:  BillyHvac replied 6 years ago.

If the light is a steady slow pulse it is "normal waiting"

If the light is steady fast pulse it is "In normal heat mode"

If the blinks are in sets, that would be a fault code. If you have the model number I can look for a manual for you. The series narrows it down a bit but there are different models within the series.

JACUSTOMER-p649u0dx- :
Do you know where the model number is?
I just want to make sure I get you the "right" number. Where should I look for that?

Expert:  gotoman for ac replied 6 years ago.

The model number is inside furnace. You have to remove top door.

Customer: replied 6 years ago.
There is a barcode on the inside of the door (once removed).
It has A342242G01
I'm going down to see if there are numbers inside the furnace itself.
Expert:  BillyHvac replied 6 years ago.

Page 21 here -

Trane and American Standard are the same unit...that is why you will see the model read as *UD.....If Trane it is TUD and if American Standard AUD.

Customer: replied 6 years ago.
I think it's what the document refers to as "flashing slow". Doesn't say what to do about it though...
Expert:  BillyHvac replied 6 years ago.

There is nothing to do because it is "normal"

The slow flash means everything is action necessary

Customer: replied 6 years ago.
Fair engouh -- but how do I know if it's "fast" or "slow"? It's normally solid green -- so something is up. And it seems louder than usual.
I've got the thermostat in "fan on" and "AC" mode. It's not hot enough for AC to trigger. Also, with the furnace panel off and holding in the panel button, while the red light steadily flashes, there is an orange light on (below and to the left of the red light) and a green light blinking (below and to the right of the red).
Expert:  BillyHvac replied 6 years ago.

The only difference between fast and slow is if the furnace is running and heating

Slow flash= dormant, everything normal

Fast flash= unit is heating, everything normal

The only time you have issues is if the blinks are in sets of 3...4 etc...

Customer: replied 6 years ago.
So...(and sorry if this is bothering you...) why is it normally solid green. And why would the red lights be on *at all* if I'm not heating (in AC mode)?
Expert:  BillyHvac replied 6 years ago.

The light would not be solid green...if it were the control would be defective.

The board does not monitor only turns the blower on. The circuit board is strictly to monitor heat related items. The furnace comes as furnace is added to it as an option. Therefore when ac is running, the board knows nothing about that at all....all it is doing is running a fan.

Do you have an issue that began this situation? or just noticed the light?

Customer: replied 6 years ago.
I did need to hose out the filter. We've been doing some construction downstairs. Dusty/dirty...
Wife thought it was "loud" in the middle of the night and turned everything off at the thermostat. When I went to investigate there was the blinking red light. I know that isn't right...but can't remember what fixes it. I am...
Expert:  BillyHvac replied 6 years ago.

Ok, this is not the first time I have had this query..Everyone assumes a blinking red light is bad. But in the case of Trane and American Standard the blinking red light is normal. As you see by the documentation on page 21...the flashing light is normal.

In the event the light were solid, that would be a problem. I am afraid I cannot cajole or twist your arm to believe the blinking light is normal......but if you look at the manual you will see it is the case.

The fact you changed filter would lead me to check the inside of the blower wheel for any debris, but the circuit board does not monitor that.

I am more than happy to further assist you...but in the matter of a blinking red light, that is simply normal.

If you would like I can opt out so the others can have a look.