Furnace Problem

Reply

  #1  
Old 01-05-18, 08:26 AM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
Furnace Problem

I have a Amana Air Command 90 gas furnace that's giving me fits. It all started with the inducer failing. It made a heck of a noise so I pulled it off and found 10 vanes had broken off. I replace with a new one and then I started to get 3 blinking light code (pressure switch open) . Had a tech come out and he said replace switch. Did that and same problem. I also went ahead and replaced the circuit board. Ran fine for a few days and now only the first startup in the morning the furnace will run for about 20 min then kick off on the same code but the inducer keeps running. After I reset the furnace works fine the rest of the day. All vents are clear, vacuum hoses good and condensate drains clear. Thanks for any help, I'm going nuts
 
Sponsored Links
  #2  
Old 01-05-18, 09:38 AM
Member
Join Date: Feb 2014
Location: USA
Posts: 2,104
Received 0 Votes on 0 Posts
Make sure the tube fitting on the switch is clear.
 
  #3  
Old 01-05-18, 09:45 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 52,729
Received 345 Votes on 323 Posts
Welcome to the forums.

Had a tech come out and he said replace switch.
Wrong. We don't guess at problems and their repairs.
I'm guessing this wasn't an actual technician but possibly a handyman ?

The first thing a tech does is to put a mater (manometer) on the pressure switch line to see if there is a problem. Since you just replaced the inducer.... that's where your problem lies. It can be as simple as a missing gasket or an air leak into the inducer chamber. It could also be an under performing blower.
 
  #4  
Old 01-05-18, 09:53 AM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
Thanks for the replies. Yes all fitting are clear. Yeah the tech cost 120 to tell me that. Won't use him again, The new inducer didn't come with a new gasket but to old one looked good. Think I should remove the old gasket and use some Hi-temp RTV ?
 
  #5  
Old 01-05-18, 10:26 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 52,729
Received 345 Votes on 323 Posts
Yes... you could use a small amount of RTV.
 
  #6  
Old 01-05-18, 02:18 PM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
I pulled the inducer and put a good bead of RTV on. I'll let it cure overnight and try the furnace in the morning. I'm still mystified as to why it only happens once or twice in the morning, then runs fine the rest of the day. If the RTV does not help I'll find a Manometer and see what's up with the vac. Ton of good info on this site, wish I would of found it earlier.
 
  #7  
Old 01-10-18, 07:44 AM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
Yesterday I had a tech come out with a manometer. Vacuum on the inducer is pulling 1,6"-1.7" and the pressure switch calls for 1.38" to close. I'm still getting the 3 blink code first couple of startups in the morning, then it settles down and works fine the rest of the day. While I'm getting the code if I pull off the hose for the pressure switch to the fire box the code clears and the furnace fires right up, Also with the cover off the firebox it starts fine. I blew out both the supply and exhaust vents with a leaf blower a week ago but maybe there is something still stuck in there. Tech said he's going to talk to a coworker and get back to me. Any thoughts on my next move? Thanks
 
  #8  
Old 01-10-18, 11:02 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 52,729
Received 345 Votes on 323 Posts
If you pull the hose off and the code clears..... something is holding the vacuum in the pressure switch line. It would have to be something at the inducer end which is strange as it's a new unit,
 
  #9  
Old 01-10-18, 11:44 AM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
Quick question. The pressure switch has 2 hoses, one to the inducer and one to the firebox. I know the one to the inducer is for the vacuum to close the switch but I don't quite get the function of the firebox hose. It seems that as soon as I pull hose off the firebox end it bumps the vacuum up just enough the close the switch and when I reconnect it runs fine. As I said it only happens the first 2 times in the morning then it will run fine all day long. Leaving on a trip soon and I would love to figure this out so the house doesn't sit cold all week. I'll report back what the Tech has to say. Thanks.
 
  #10  
Old 01-18-18, 08:43 AM
Member
Thread Starter
Join Date: Jan 2018
Posts: 6
Received 0 Votes on 0 Posts
Well I'm 0-2 on Techs. Second Tech never called back. I should of known he was a Dud when he complained a few times that he hates these kind of service calls. I've learned through this ordeal that your kind of on your own when it comes to parts, service etc. I hope I just got unlucky but I'm kind of tired of paying for calls and the Techs don't seem that interested in helping me figure this out. Anyway, I seem to be losing vacuum the longer the furnace runs. Anytime over about 40mins and the pressure switch opens. If I figure this out I'll report back. Thanks
 
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
Display Modes
 
Ask a Question
Question Title:
Description:
Your question will be posted in: