Furnace blower won't stop...but there is heat when below temperature
#1
02-26-17, 09:15 AM
Join Date: Feb 2017
Posts: 4
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Furnace blower won't stop...but there is heat when below temperature
hi guys..furnace on for hours ...when temperature is reached, it blows cool air...when it falls below temperature, it blows warm air...
room temperature seems to be regulated..kept at the preset temperature.. according to the thermostat and fan is set on AUTO...it's just that the fan won't shut off after the preset temperature is reached
I have an old 80s lennox gas furnace with an electronic type of filter...
what to do?
room temperature seems to be regulated..kept at the preset temperature.. according to the thermostat and fan is set on AUTO...it's just that the fan won't shut off after the preset temperature is reached
I have an old 80s lennox gas furnace with an electronic type of filter...
what to do?
#2
02-26-17, 10:01 AM
Group Moderator
Welcome to the forums.
Please post the model number.
You need to remove the burner access door to locate the furnace ID tag.
It will be inside on the side wall near the burner.
Please post the model number.
You need to remove the burner access door to locate the furnace ID tag.
It will be inside on the side wall near the burner.
#4
02-26-17, 12:51 PM
Group Moderator
1993 would be about right.
The bad news is that your control board controls blower on and blower off via timers.
If you open the blower door you should see the control board. Remove the thermostat wire from the G terminal and put the blower door back on. See what the blower does now.
My guess is that it will continue to run requiring a control board replacement.
The bad news is that your control board controls blower on and blower off via timers.
If you open the blower door you should see the control board. Remove the thermostat wire from the G terminal and put the blower door back on. See what the blower does now.
My guess is that it will continue to run requiring a control board replacement.
#5
02-26-17, 01:33 PM
Join Date: Feb 2017
Posts: 4
Upvotes: 0
Received 0 Upvotes
on
0 Posts
yep, i removed the green wire from the G terminal and it's still running, blowing cool air...so that means i have to replace it with a new board, right? Is there a place to look up the right board part/model for the furnace? Thanks, PJmax
#6
02-26-17, 01:44 PM
Group Moderator
Looks like an OEM 48K98 board. Wherever you get it from....you must give them the full model number and possibly the serial number for verification.
I get parts thru a distributor so I let him do the looking up.
Buy Genuine HVAC Repair Parts at Hvac Parts Shop
Lennox 48K98 OEM Control Circuit Board | eBay
discount furnace/lennox/48k98-oem-control-circuit-board
I get parts thru a distributor so I let him do the looking up.
Buy Genuine HVAC Repair Parts at Hvac Parts Shop
Lennox 48K98 OEM Control Circuit Board | eBay
discount furnace/lennox/48k98-oem-control-circuit-board
#7
02-26-17, 02:00 PM
Join Date: Feb 2017
Posts: 4
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Got it, Pete..that looks like the one i have....
btw, there's nothing else to check, no other likely cause, thermostat should be ok, am i correct?
btw, there's nothing else to check, no other likely cause, thermostat should be ok, am i correct?
