Weil McLain PIDN boiler not lighting consistently

Reply

  #1  
Old 02-05-13, 08:25 AM
Member
Thread Starter
Join Date: Feb 2013
Location: usa
Posts: 1
Received 0 Votes on 0 Posts
Weil McLain PIDN boiler not lighting consistently

NJTrooper, why would it make a difference if the ignition sensor is cleaned or not. The pilot flame is heating it with a substantial flame clean or dirty, I would think it should still send an appropriate signal if it is functional. My system is behaving similar to what is described in this thread. It has become intermittent on when the main burner kicks on. The system continues to repeat attempts to light becase all three of my zones are calling for heat because I can hear the circulating pumps running. If I turn the system off for an hour or so and then try again, it will sometimes light on the first, or subsequent attempts. This morning, after attempting to light it's self all night, it did light after being shut off for about an hour. It shut down within a short time however. Previously it would stay continuously on until it brought the house up to temp from the 50's to the selected temp in the high 60's. Not today though, it fired up and shut down quickly. I continued to cycle the power to bypass the normal 5-6 minute cycle and force the closing/opening of the damper and the ignition cycle with no success. I had pulled the covers off and vaccumed out the main burner, around the pilot and sensor, then turned the blower on and blew things out. I pulled most of the blade connectors off and reseated them to insure good contact. That resulted in the system lighting when I finished. Shortly there after, it became intermittent again. I finally called for service yesterday, the tech cleaned and conducted general service/maintanence, although I'm not sure what that consists of. He reported that the system seemed to be working normal and did not fail to light after repeated starts of the system. By 7 pm when I got home from work, not working again. He suggest changing the pilot assy. I'm thinking the ignition sensing control module. Any thoughts?








Mod Edit: All above posts are regarding this thread. Closed original..

http://www.doityourself.com/forum/bo...sistently.html
 

Last edited by lawrosa; 12-17-13 at 10:24 AM. Reason: closed original thread. Erroneous post were being added..
Sponsored Links
  #2  
Old 02-05-13, 08:49 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 1 Vote on 1 Post
why would it make a difference if the ignition sensor is cleaned or not. The pilot flame is heating it with a substantial flame clean or dirty, I would think it should still send an appropriate signal if it is functional.
I believe you may be thinking in terms of a "ThermoCouple", which you are correct that it really wouldn't need cleaning. Thermocouple words under a completely different principle in that it actually GENERATES A VOLTAGE which signals the controls that pilot is lit.

The newer systems use a method known as "FLAME RECTIFICATION" whereby a CURRENT is actually passed THROUGH THE FLAME. This CURRENT is in the order of MICROamperes... very small!

If there is corrosion on the "FLAME ROD" this can impede the flow of this miniscule current, just as a bad ground connection could/would.

Try a Scotch Brite pad on that rod and see how it goes...
 
  #3  
Old 02-05-13, 10:45 AM
Member
Join Date: Nov 2010
Location: usa
Posts: 19
Received 0 Votes on 0 Posts
follow-up from OP

I ended up replacing the control module, and that has fixed the issue.

It was time consuming, and frustrating, to trouble shoot the problem, but in the end, I was confident that I had eliminated all the other possible problems.


http://www.doityourself.com/forum/bo...sistently.html
 

Last edited by lawrosa; 12-17-13 at 10:26 AM.
  #4  
Old 12-17-13, 08:11 AM
Member
Join Date: Feb 2009
Location: Baltimore
Posts: 6
Received 0 Votes on 0 Posts
Glad I found this thread. I've got the same unit with the same problem. Had a guy out from one of the companies listed on the WM website and he took $450 off me checking it out and replacing the pilot/flame sensor which didn't help in the end. I understand that it's difficult to narrow down an issue like this but I wish he had just admitted that he didn't know if what he was doing would help. That company shouldn't be on the WM website, I'm thinking.
 
  #5  
Old 12-17-13, 09:27 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 1 Vote on 1 Post
Do you have a question? or did you only stop by to vent?
 
  #6  
Old 01-07-14, 04:59 AM
Member
Join Date: Feb 2009
Location: Baltimore
Posts: 6
Received 0 Votes on 0 Posts
Got the control module, changed it out in 20 minutes a couple of days ago, and haven't heard the ignition problem so far.

I called Weil-McClain to complain about the guy who came out. The lady told me they don't really check out the companies that are listed on their website. Ridiculous!

Like I first stated, I'm glad I found this thread. If I have a question I'll start a thread like most folks do.
 
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: