What action is needed w/System Lockout?

Reply

  #1  
Old 10-14-07, 08:35 PM
S
Member
Thread Starter
Join Date: Oct 2007
Posts: 1
Received 0 Votes on 0 Posts
Question What action is needed w/System Lockout?

Furnace isn't providing heat first time turning it on this season. LED diagnostic indicator sequence is identifying an external to board failure; red light 1 flash: system lockout. What does this mean & what action do I need to take? Am not finding info. in documentation. Comfortmaker Super High Effeciency Gas Fired Furnace with Total Furnace Control, Model 50A50 - 133; @15 years old, no prior issues. Might it be thermostat or limit switch related? Blower, intake, exhaust appear operational.
 
Sponsored Links
  #2  
Old 10-15-07, 07:25 AM
Jay11J's Avatar
Member
Join Date: Sep 2001
Location: Rochester, Minnesota
Posts: 18,427
Received 0 Votes on 0 Posts
I"ll see what I can find.. But look on back of the blower door, there may be some info on there for you.
 
  #3  
Old 10-15-07, 01:02 PM
D
Member
Join Date: Aug 2007
Posts: 2,021
Received 0 Votes on 0 Posts
Originally Posted by SandhillCrane View Post
Furnace isn't providing heat first time turning it on this season. LED diagnostic indicator sequence is identifying an external to board failure; red light 1 flash: system lockout. What does this mean & what action do I need to take? Am not finding info. in documentation. Comfortmaker Super High Effeciency Gas Fired Furnace with Total Furnace Control, Model 50A50 - 133; @15 years old, no prior issues. Might it be thermostat or limit switch related? Blower, intake, exhaust appear operational.
It's a little confusing:

One flash is related to a test sequence for the indoor fan motor [IOW- the fan that circulates air thru the house AND NOT the combustion air fan motor]. Are you sure you're not seeing 2 or 3 flashes? There related to a test sequence for the heat cycle. What happens when you reet the power then set the thermostat fan switch to auto and the system switch to off? Does the indoor fan start? When you say that blower, intake and exhaust appear operational exactly what does that mean? Do you mean the indoor fan and the combustion air fan run on a call for heat? If yes, does the ignitor glow? If no, check the pressure switch. Maybe it's stuck closed? There are two common failures on these units. First is a cracked heat exchanger which prevents a vacuum from being drawn thru the furnace. Second, on the fan wheel side of the combustion fan there is a restrictor ring on the fan intake. Over time, the little pins that hold it in place dissolve. Take the combustion fan apart and check it. Let us know what you find.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: