Intermittent ignition lockout on Hydrolevel 550 low water cutoff

pcolburn2

I am getting intermittent ignition lockout on our Weill McLain EGH 125. We have a Hydrolevel 550 LWCO. There is plenty of water in the boiler and I know there is only pipe dope and no PTFE tape on the Hydrolevel. This is one of two LWCO because this is one of two safety devices because it is a commercial boiler. I don’t know if the other LWCO is tripping. We are simply resetting the LWCO to get back on line.

Are these devices in series? Could one be tripping the other? Do I just need another 550? It is less than one year old in service.

Any thoughts or ideas would be much appreciated.

neilc

they should be wired in series,
one would not trip the other,
the manual reset is likely doing it's job,
why is the water dropping out ?
post pictures of the whole boiler, floor to ceiling,
and of the 2 LWCOs,
water clear? (picture)
bouncing in the sightglass?
pressure when it's running?

pcolburn2

Water is clear. It was fully blown down this week in anticipation of cold season and then refilled to the correct water line.

No bouncing in the sight glass I am aware of and no pressure issues because it has not dumped via the relief valve.

Could it just be a bad board in the Hydrolevel 550?

neilc

pcolburn2 said:

and no pressure issues because it has not dumped via the relief valve.

I'm gonna come back to this, but right now,
you can have pressure issues with, or without, blowing the safety valve,
if you've been blowing the safety valve, you REALLY have pressure issues,
has the pigtail been checked for clean and clear?
what pressure do you see on the gage when the boiler is running full steam?
really would like to see a second pressure gage, maybe Tee'd under the safety valve,

neilc

have you been able to watch it trip the manual LWCO ?
is the water leaving the sightglass?

EBEBRATT-Ed

If you have two low water cutoffs on a commercial boiler the one mounted higher is a non manual reset and the lower control is a manual reset.


If the lower one is tripping you have a problem. The lower one should never trip during normal operation.

I would suggest watching it to see if the water level is bouncing. Also check and clean the gauge glass connections to make sure you have a good reading of the actual water level

HVACNUT

Have you cleaned or tested the probe?

pcolburn2

Pigtail has not been checked to be clean and clear as far as I know.

The production of steam can’t be the issue because it has been so mild here and we just made steam for the first time after this issue started because we jacked up the thermostat. It does circulate hot water to an indirect HTP tank.

Are you saying the primary or secondary pressuretrols could be tripping the LWCO on an intermittent basis?

pcolburn2

Water is not leaving the sight glass. I know we are not losing water because we replaced a bunch of wet return piping recently and it has not filled a drop via the feeder since then.

It is an interesting point about the sight glass but a plumber recently did a complete rinse and refill of the near boiler piping (wet returns) and heat exchanger and this is still happening.

I agree it could just be that the probe or board in the LWCO is faulty but it is nearly new equipment.

neilc

has the safety valve tripped in the past ?
does the pressure gage move? to what?

pcolburn2 said:

Pigtail has not been checked to be clean and clear as far as I know.

The production of steam can’t be the issue because it has been so mild here and we just made steam for the first time after this issue started because we jacked up the thermostat. It does circulate hot water to an indirect HTP tank.

Are you saying the primary or secondary pressuretrols could be tripping the LWCO on an intermittent basis?

none of the safeties, or controls, directly trip another,
they're all wired in series,
if any one trips, the whole boiler circuit shuts down,

however, if the pigtail is blocked, then the Ptrols, and that single gage, don't see the pressure in the boiler, and can't turn the boiler off at pressure setpoints,
and then you build excessive pressure, which would push water out of the boiler,
and that could trip that manual LWCO,
However, your primary should have shut you down first,
the primary sensor and control need to be checked,
and the pigtail also,

and real excessive pressure blows the safety valve,
has that safety valve opened in the past ?
#pigtail

pcolburn2

Yes the pressure valve did open and dump in January 2021, shortly after the boiler was installed. The ptrol was reset or serviced by the installing plumber, if I recall. It has not dumped since then.

I did not think making hot water for an indirect could wreak havoc on the pressure devices. This is assuming that the pigtail is clear, of course.

EdTheHeaterMan

pcolburn2 said:

I am getting intermittent ignition lockout on our Weill McLain EGH 125. We have a Hydrolevel 550 LWCO. There is plenty of water in the boiler and I know there is only pipe dope and no PTFE tape on the Hydrolevel. This is one of two LWCO because this is one of two safety devices because it is a commercial boiler. I don’t know if the other LWCO is tripping. We are simply resetting the LWCO to get back on line.

Are these devices in series? Could one be tripping the other? Do I just need another 550? It is less than one year old in service.

Any thoughts or ideas would be much appreciated.

Let me reword your query as it is actually happening.

I am getting intermittent ignition LWCO lockout on our Weill McLain EGH 125. We have a Hydrolevel 550 LWCO. There is plenty of water in the boiler and I know there is only pipe dope and no PTFE tape on the Hydrolevel. This is one of two LWCO because this is one of two safety devices because it is a commercial boiler. I don’t know if the other LWCO is tripping. We are simply resetting the LWCO to get back on line.

Are these devices in series? YES Could one be tripping the other? NO Do I just need another 550? Probably not It is less than one year old in service.

Any thoughts or ideas would be much appreciated.

The manual reset LWCO is there to let you know that the automatic LWCO has failed to operate properly. Find out why the automatic LWCO is not doing its job.

pcolburn2

Are you saying it could be a communication issue between the LWCO and the auto feeder? Note that adding water to the boiler has never cause good ignition because it was simply not needed, only resetting the LWCO turned the boiler back on.

Are you leaning to this being a pressure issue like some others have mentioned?

EdTheHeaterMan

I would look at the near boiler piping and LWCO locations, and insist the corrections be made under warranty for material and workmanship of the installing contractor. Look at this diagram from the IO manual.


The location of the automattic LWCO (or primary LWCO) should be in the opening marked C. The secondary LWCO with manual reset should be located in the opening marked T. If the boiler does not have that opening (then the wrong end section was specified) then look at the other side for opening marked P for the secondary manual reset LWCO location.

I'm not sure I like the location selected by the installer "on the return piping". I have limited experience with EGH steam boilers but there are others on this site that do. Perhaps someone else will tell you that is acceptable. But I'm not a fan.

Not a fan of the Header design either

neilc

yeah, the primary is also signaling the water feeder, that communication is bad, or should say, the sensor to the control is bad, or that that primary needs to be ferreted out, dirty sensor, bad board, don't know, but needs to be ferreted,

you say you're not needing to add water, but by the time you go reset the manual LWCO, water has returned to normal, whether it's pressure(pigtail) pushing water out, and that the primary LWCO isn't doing its job,
you have to be there and watch it,

EdTheHeaterMan

Looking at the risers, they don't appear to be high enough, they don't appear to transition to 4" and they are connected to a point in the middle of the two risers, not at the end as indicated in this diagram from Weil McLain. I also believe the manual LWCO may be installed dangerously lower than the minimum safe water level.




You may need a different contractor to solve this and maybe an attorney if the original installing contractor does not honor his warranty. Check your contract for the job and see if there is anything that says something like installed per manufacturer's instructions, because is is not installed that way.

neilc

Damn,
there's 2 "P"s,
and I saw the top one first,

Jamie Hall

Sort of a bottom line comment on all of the above.

The secondary, manual reset low water cut out is a manual reset for a reason. It is to inspire the operator to find out why it sensed low water, and fix the problem, before attempting to run the boiler again.

Let me state that in a separate line: It is to inspire the operator to find out why it sensed low water, and fix the problem, before attempting to run the boiler again.

Got it?

The low water cut off, being only a year old, is likely not the problem -- but even if it is, it must be corrected before that boiler can be run safely. The fact that the primary automatic LWCO doesn't seem to shut off the boiler is another problem and must be remedied before the boiler can be run safely. And.. if the pressure control (s there only one? If this is a commercial installation, there should be two on separate pigtails, the higher one manual reset -- same logic as the LWCOs) does not shut off the boiler at or near it's marked pressure, that is another problem which must be remedied before the boiler can be run safely.

That boiler is a catastrophe waiting to happen. The problem(s) may be simple -- perhaps the two LWCOs are wired in parallel rather than in series? Simple to fix. But don't think of running it, except possibly to test something and under close supervision until the fixes are made and proven.

neilc

I don't think anything is wired parallel,
but an original question was if one control/safety, could be tripping a different device

pcolburn2

I agree that the next step is to see if the primary McDonnell Miller LWCO on the left hand side of the boiler is tripping in lockstep with the Hydrolevel on the right hand side of the boiler.

Jamie Hall

neilc said:

but an original question was if one control/safety, could be tripping a different device

Nope.

pcolburn2

Here is another wrinkle: the boiler operated fine for a little less than a week ( Tuesday to today) after the PTFE tape was taken off the Hydrolevel and replaced with only pipe dope. I can assume the MM on the left hand side is also installed with PTFE tape but we have not taken it off yet.

I was feeling good for a few days that our issue was resolved. I understand that PTFE tape can cause issues with the proper grounding of the LWCO.

neilc

and the pigtail

pcolburn2

Understood. I think what you all have taught me here tonight is that I need my plumbers to closely examine the operation of or service the primary LWCO as well as the two pressure devices and the pigtail.

I doubt it is feasible to rework the risers and headers due to ceiling height issues and the placement of the secondary LWCO looks strange but perhaps at a reasonable water level given one of the diagrams somebody shared.

neilc

pcolburn2 said:

Here is another wrinkle: the boiler operated fine for a little less than a week ( Tuesday to today) after the PTFE tape was taken off the Hydrolevel and replaced with only pipe dope. I can assume the MM on the left hand side is also installed with PTFE tape but we have not taken it off yet.

well it's about time you shared that , , ,
#smiling

neilc

honestly,
maybe your plumbers might oughta stick to plumbing,
steam is a different animal,
have you tried
https://heatinghelp.com/find-a-contractor/

pcolburn2

Yes but if the primary LWCO does not talk to the Hydrolevel that is tripping why is my comment about PTFE tape on other devices so important?

EdTheHeaterMan

neilc said:

I don't think anything is wired parallel,
but an original question was if one control/safety, could be tripping a different device

No. One LWCO will not cause another LWCO to operate any differently. One pressure switch will not cause another pressure switch to trip. These are not circuit breakers that measure electrical load and cause something else to trip.

Think of it like a switch on the wall that will operate a light bulb in a socket with a pull chain switch. The wall switch can not cause the pull chain switch to open, nor can the pull chain switch cause the wall switch to change position.

All the limit switches are in a series circuit. ALL the switches must be closed for power to the burner. Any one of the switches that opens will break the circuit to the burner. If any second switch opens after the burner stops by the first opened switch. The burner does turn MORE off. It is already off and OFF is OFF! Once the burner is off temperature may continue to rise slightly for a very short time, but very quickly the temperature and/or pressure will begin to drop and that second safety device that opens will close in the time it takes to return to the lower condition or lower cut in pressure, or temperature or higher water level. Unless the control is a manual reset.

And @Jamie Hall hit that nail on the head with his comment (twice).

pcolburn2

I’m curious as to why there is so much concern about the primary LWCO not tripping. It is not tripping because there is not a TRUE low water condition at that specific level.

I suppose there could be surging and rising water lower in the boiler and that is causing for the Hydrolevel to trip but that would be literally be a brand new condition after a year of normal operation and a recent full boiler blow down. There is some Squick in the system but this was added only after this issue began.

I still keeping coming around to the conclusion that maybe the two LWCOs are wired in parallel of perhaps I just need a new probe and/or circuit board (new unit) for the Hydrolevel that is tripping intermittently.

I agree that the pressure devices need to be put on separate pigtails. I will have that remedied by the installing plumbing and heating company before their warranty period runs out later this year.

neilc

you don't use tape on the probes because
->(the manual says so)<- the tape can, and likely in your case has, isolate(d) the probe from the boiler, not allowing it to complete its electrical circuit,
using paste will, at some point, allow threads to ground to boiler for complete circuit, as the probe snugs up in the boiler,

if your 2 LWCOs were wired parallel, then the burner would not be locking out on the secondary manual reset,
the boiler would fire when or if the primary auto reset itself,
2 switches wired in parallel, either one on, circuit on

and as everyone has said, the primary should be tripping first, before you get down to a secondary and lockout,

isn't there a test button on the primary?
or better yet, sit with the boiler and slowly lower the water level, the primary should cut out the burner,

squick, get rid of it, use straight water,
or if you have water quality concerns, get a specialist in there to treat for what you need,
loose the squick

JUGHNE

Are you certain that the manual LWCO is lower than the auto LWCO?

You say the pressure relief valve opened...what is the manual reset pressure control set at? If the relief opened than they must have had it set over 15 PSI or it would have opened. IMO, 5 or 7 would be a safer setting.

With the high pressure you have had could the steam have pushed the water out of the return piping and left the manual LWCO dry to open?

Or is the indirect pump sucking water out of the lower return piping perhaps leaving the piping of the LWCO dry??

How about a picture of that piping with a little more light on the right side of the boiler.

Is this a single pipe system....what do you have for steam main venting....pictures also please.