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Pressuretrol failed after a month?

NYCDave Member Posts: 78
Hey everyone,

We recently converted from oil to gas and installed a burnham IN8 Independence boiler.

We had a lot of surging issues initially but that settled down after some skimming and the plumber also use some detergent or other.

However, recently wr’ve been having some spitting radiators, both at the vents and also at the valves. A few days ago I noticed the pressure on the boiler dial getting up to about three PSI which seemed high, so I dropped the pressuretrol (Honeywell) from around 1.5 to around .5, about as low as it could go space (subtractive differential is 0.5).

This morning I noticed the valves were spitting worse than before, went downstairs, and saw of the pressure dIal was reading nine psi. It’s been fluctuating between 0 and 9 since then, going to zero when the boiler cuts off, and rising steadily until ~nine. I believe it’s cutting out on the thermostat, not on pressure…

I’m attaching a picture of the pressure dial and the pressure controller settings.

Is it possible that the pressure controller died after only a month since the original installation? Anyway to debug/test this?

How hard is it to change a pressure controller? Is that included in the boiler warranty?

Thanks for any advice!


  • neilc
    neilc Member Posts: 2,673
    it is possible,
    that the work and cleaning chems and surging stirred the pot up and maybe gunked up the Pigtail under your P trol,
    have you checked or cleaned the pigtail ?

    known to beat dead horses
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    What does the plumber say about this early failure?
    My experience with pressuretrols has been that setting them as low as they can go may sometimes disconnect the internal control linkage, rendering them inoperative.
    I would suggest a good skimming of your boiler, cleaning the pigtail, replacing the water inside with pure water, and the installation of a Vaporstat, and low pressure (0-3 psi) gauge.—NBC
  • adambnyc
    adambnyc Member Posts: 260
    Also, I’m pretty sure that the pressuretrol lowest is 1.5. You could have disconnected the internals as stated.
  • adambnyc
    adambnyc Member Posts: 260
    Also, and just to be sure, did the plumber prime the pigtail after install? Supposed to fill it with a bit of water so it doesn’t get hit by steam.
  • adambnyc
    adambnyc Member Posts: 260
    edited January 2018
    Some pictures of the install and near boiler piping would help. And you have the bane of my boilers existence for the LWCO.. cycleguard. Shuts the boiler off every 10 minutes for 3 minutes to allow water to flow back to the boiler. Shouldn’t need that at all if they system is working properly.
  • Fred
    Fred Member Posts: 8,542
    I agree that you need to check and clean the pigtail. If the boiler wasn't skimmed properly, or an additive was put in the water, it can clog the pigtail. Once that is done, set the Pressuretrol properly. Set the "Main" to about "2"PSI and set the Differential to 1.5 PSI. That will give you a Cut-in of .5PSI and a Cut-out of about 2 PSI. Given this is a new installation, if the boiler was properly sized to your connected Radiation EDR, it should rarely, if ever reach cut-out pressure and the Pressuretrol acts only as a safety control. Do you know the total EDR of your radiators? How well does that match up with the "Sq.Ft. Steam rating on the boiler plate?
    Mark NCanucker
  • NYCDave
    NYCDave Member Posts: 78
    Hey guys, thanks so much for the advice! Is it really true that if you set the pressure controller to the lowest setting you actually disconnected? That seems like an unbelievably dangerous quotes ‘feature’!!! If I turn it back up to higher setting do you guys know if it will reconnect? Or is it pretty much disconnected for good once I set it all the way down? In fact I did turn it back up to little bit higher but it made no difference.

    At this point the situation has gotten much worse as well, as I just woke up and the thermostat was reading 10° above the setpoint, the boiler pressure was at 16 PSI, and there was water in the relief valve bucket… No idea how a boiler can keep running past the thermostat cut off? ny ideas/advice for that? At the moment I had to shut it off manually.
  • j a_2
    j a_2 Member Posts: 1,801
    Post some pictures of the boiler piping.
    How many rooms are in your house?
    It is very possible you did exceed the adjustment limits, and rendered the pressuertrol inop..reconnecting it is a minor task...
    I highly suggest Mr. Installer get on back over there,and do what a steam guy does, figure it out and fix it...honestly with a new boiler you the owner should be hands off...
    It was a competent installer,correct?
  • NYCDave
    NYCDave Member Posts: 78
    edited January 2018
    PS, I checked checked the thermostat and it’s working fine, it opens the circuit when set below the current temperature and closes it when it’s set above. However the two wires from the wall to the thermostat show a closed circuit (no resistance)... so it seems something is shorted out somewhere in the boiler electricals? Has anyone ever had a bad thermostat relay?
    Also weird that the thermostat circuit was working Fine before and now it stopped… I would assume boiler electronics should be pretty resistant to heat, what else could cause them to go bad? Also weird that the pressure controller seems to have failed before hand, maybe that’s electrical as well?
  • Fred
    Fred Member Posts: 8,542
    There is a linkage that the screw(s) on top of the Pressuretrol connect to. Look inside ans behind the scale and see if that link has fallen off the screw. If so, lift the like up and turn the screw back onto that link.
    EBEBRATT-Ed Member Posts: 15,346
    I would get the installer back their pronto and get this checked out.

    Steam or water out of the relief valve is semi serious
  • ratio
    ratio Member Posts: 3,605
    NYCDave said:

    ...the two wires from the wall to the thermostat show a closed circuit (no resistance)... so it seems something is shorted out somewhere in the boiler electricals?

    IDK about your other issues, but low resistance would be expected on the load side of an electromechanical system (non-electgronic controls) and not unexpected on electronic controls. A better test would be current while not firing (should be zeroish) and while firing (should be noticeably & repeatably higher, electromagnetic more so).

    Like @Fred said, check the mechanical linkage on the bottom of the pressuretrol, or post a pic of it.

  • NYCDave
    NYCDave Member Posts: 78
    edited January 2018
    So this turned out to be a fun problem... Plumber came by Monday morning because obviously lack of pressure and thermostat cut off is a serious problem. Confirmed the problem was not with the trol or stat because short circuiting either did not stop the boiler... discovered that disconnecting the neutral wire from the cycle guard to control box resolved the problem... but has no idea why... Swapped the cycle guard for a safeguard but didn’t change the problem. we left it at that for now... Now the safeguard only has power when the boiler is on… Strange but it works.

    I’m guessing there must be some screwed up wiring somewhere but haven’t had the time to track it down, for now this works. , thank goodness...

    Strange thing is that the thermostat was working for the last month and a half since they installed the system… Guessing something shorted out in the cycle guard due to wrong wiring but not sure. Also guessing the pressure cut off was never working at all… until things got really cold it was always just cutting out on temperature without building up to much pressure.

    I think if I will wait till summer to try to resolve this or may post some photos of the wire connections if there are any electricians out there.

    Good news is that now that the pressure cuff is working well, the water hammer and spitting vents and valves have gone away! Nice to see how quiet the system can be when it’s working. Of course the weather is much warmer now… We’ll see how it goes when things get really cold again.