American Standard furnace problem

[MarkG]

Our 'Freedom 80 Comfort R' heater from American Standard is only giving us freedom from HEAT! :S We're getting a '3 red flash' error code, which according to the cover is a pressure switch problem.

Can any guys on here tell me if this is something homeowner-serviceable or what exactly this error code means?

Thanks!

 

[ebasista]

Google is your friend.

http://www.diychatroom.com/f17/3-flash-code-american-standard-freedom-90-furnace-973/


You have power, but what is happening it is going thru its safeties. In this case does the small exhaust blower turn on at all? If it isnt then thats why the pressure switch isnt being made. If the small exhaust blower is turning on, then the switch is bad (or tubing), or the exhaust blower isnt flowing enough (unlikely).

The exhaust blower's purpose is to purge the furnace of gas prior to startup so it doesnt blower up

 

[zmaxmotorsports]

What he said.
What is the furnace doing when it calls for heat and what isnt it doing?

 

[LS6 Tommy]

Those DP switches are a common failure point. They usially look like this (or very similar, but made out of metal):

They're usually right up front or at least easily accesible. If the draft blower is running and you don't get 24vac on both of the contact terminals that are in use (if there are three terminals like the picture, usually only 2 have wires on them. Test those 2 terminals.) it's probably bad.

Tommy

 

[My Old Tools]

Check the hoses for blockage or cracks.