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Lochinvar Knight Boiler PC Board problems

DanHolohan Member, Moderator, Administrator Posts: 15,444
This discussion was created from comments split from: Lochinvar Knight boiler problems.
Retired and loving it.


  • Hititnow
    Hititnow Member Posts: 1
    Lochinvar Knight Boiler PC Board problems


    I am so glad you guys are here and have this site. I have a Lochinvar Knight boiler model WHN199.

    I have only 1 question. It is apparent and well known that there is a defect in the PC Board that this model is manufactured with. I was told this by an authorized LK distributor/service/licensed plumber. He told me that he has been replacing the pc board on this model for over a year and a half (1.5 years).

    MY QUESTION: How long has this been a known problem / How long has Lochinvar Knight been replacing the PC boards on this model under warranty? 2 years? 5 years? 10 years more?

    I would be grateful for anyone who could provide me with a substantiated answer.

    Thank you very much.
  • delta T
    delta T Member Posts: 863
    I have

    no knowledge of this problem. I have been installing WHN (older version was the WBN) and KBN model lochinvars for about six years now and have had only two issues with defective parts (neither of which were the board). I don't believe that I have ever installed specifically a WHN199 but I am pretty sure they all have exactly the same control board in them. Even the floor mount (KBN) models have the same control. I searched online for any references to this "well know problem" and the only one I found was this post so I am kind of confused. Please let me know if there is a specific service bulletin that you found, or anything like that as I do have several WHN's installed and would like to know if there is a potential problem with them.

    BTW I assume you are referring to the main PC board and not the low voltage connection board?
  • Ironman
    Ironman Member Posts: 6,597
    Installed Several...

    Never had a problem or heard of any such thing like you've been told.

    You've tagged onto the end of an existing thread. In order to stay on topic, we don't do it that way around here. You should start this as a new thread if you want more responses.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Dave_hd
    Dave_hd Member Posts: 1
    Lochinvar problems

    Michigan winters can be harsh, decided to "upgrade?" to a higher efficiency model in that our old Weil-McLain? boiler had been good to us, but must have been 50 years old, at best 60% efficient.  The old boilers worst repair was a pump - easy fix, couple hundred bucks - do-it-yourself.  I decided on the Lochinvar Knight high efficiency.  Bad decision.  Problems from the start.  Called in the installer several times who advised me to reset, reset, reset,... these new boilers are problematic.  Well he went out of business, called Lochinvar to get a "factory authorized" tech's input.  He replaces blower and main valve for $1,400 (this thing's not 4 yet).  Call the company rep who is extremely rude saying it's my fault for relying on the installer to get me to reset.  I tried to at least get rebuilt spares in exchange for the parts removed - company would not support the boiler. 

    My experience - buy someone elses boiler, this one's headaches.
  • irog
    irog Member Posts: 2
    hi there, i'm irog... our School Lochinvar KTXL 725 model always Lockout (everyday). Our Grundfos Magna 3 pump will trip off then the boiler will run until it reach the high limit setting, will turn off due to Automatic Reset High Limit, will run again and it will lockout on Manual Reset High Limit. we used to reset the unit every morning and its such a waste of time for this too EXPENSIVE modern type of boilers.

    Any suggestion from the experts out there will be highly appreciated..! by the way, our location is Gallup, New Mexico, USA.

    and the boiler is designed for cascade system but not yet hook up by the contractor(nowhere to find). right now only one boiler is heating the school and it seems malfunctioning.

  • irog
    irog Member Posts: 2
    one more thing...we are using the boiler heat in our heat pumps.
    thanks again.
  • gennady
    gennady Member Posts: 830
    edited April 2016
    if you are using boiler for heat pumps, then boilers should run at 120F. automatic reset is set for 180, manual reset at 210. you need to set up PID to modulate boilers around 120F. Boiler should never be turned off by high limit.
    JUGHNE Member Posts: 8,980
    The pump trips out first, is that right?
  • gennady
    gennady Member Posts: 830
    pump must be controlled via control contracts, not powering on and off. Also, it must be properly installed.

  • Steve Minnich
    Steve Minnich Member Posts: 2,680
    Like so
    Steve Minnich
    Minnich Hydronic Consulting & Design, LLC
    [email protected]
  • Boring
    Boring Member Posts: 26
    Stumbled upon this post---searching for "life expectancy" of Knight Boilers KBN080 in particular---- We had the main board crap out on ours last year --- expensive--- there was also an issue with the ignition counter programmed into the board---I used to track all of that information annually, just for the heck of it.... and one year the counter went nuts----read like 100000 cycles and stuck there---- someone on this sight indicated there was a software bug somewhere--- Our boiler is about 10 years old and seems more noisy this year---can't really pinpoint what the noise is --- pumps or blower....
    I am happy with Knight---probably should have replace the whole unit last year when the board crapped out---that was about 1/3 the cost of a new boiler...!
  • Jamie Hall
    Jamie Hall Member Posts: 17,152
    May I make a humble suggestion to the various posters with problems? Make sure that you, and the technician with whom you are working, really understand how to operate the equipment and how it should be set up before you attack the equipment itself as being the problem... boilers, unlike smartphones, are not plug and play.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Gordy
    Gordy Member Posts: 9,514
    Smart phones have manuals to. Nobody reads them either............