LWCO Malfunctioning? (Video Included)

zackwatt

I started to notice the water level in the sight glass getting close to disappearing, and not triggering the LWCO. When the LCWO would step in, it short cycles the burner over and over, this also seems to interrupt the call fresh water. This happens until the condensate pump eventually kicks in.

I decided to test the LCWO, I drained the water to simulate a low water condition and shot the video below...

https://www.youtube.com/watch?v=jsymZet_YGU

I have two issues really: whats causing the LCWO to not sense correctly, and is it operating correctly when it does?

zackwatt

Any thoughts?

STEVEusaPA

If you drain some more water does it work? Either it's not wired right to feed water, it's not working, or there's a delay to wait for the condensate to return.
The LWCO should shut the burner off. If the water level drops and it doesn't do that (assuming it's wired right) it needs to be replaced.
That boiler needs to be skimmed.
Is this a new problem?
I do see the light go out in the LWCO, when that happens, is any power going to the water feeder? I also noticed a valve closed, but that appears to be a fast fill valve.
If you ok with electric, I would first go thru and start checking, tugging on wire nuts. Then start checking the sequence of operations with my meter.
If you're not ok, I would have a tech do it.

johnnyh13

fill water up manually and see if boiler comes on.

Steamhead

If you can't solve this easily, call a pro. A LWCO that doesn't work can let the boiler fire with no water in it, which will crack the cast-iron and you'll need a new boiler.

ChrisJ

If I had any question as to my LWCOs ability to do it's job I'd replace it immediately.

Fred

Have you taken the LWCO probe out and cleaned it with some fine steel wool? Maybe even replace the probe. Don't use teflon tape tape on it when you put it back as it needs to ground to the boiler block. It may need to be replaced. With it switching on and off like that, it probably isn't allowing enough time for the water feeder to activate.

ChrisJ

Fred said:

Have you taken the LWCO probe out and cleaned it with some fine steel wool? Maybe even replace the probe. Don't use teflon tape tape on it when you put it back as it needs to ground to the boiler block. It may need to be replaced. With it switching on and off like that, it probably isn't allowing enough time for the water feeder to activate.

Sigh,
Fred, you have to use thread sealant on the probe, its NPT.
3 wraps of PTFE tape, or some pipe dope are required or it will leak.

The warnings are not to go crazy with PTFE tape or it may not ground good to the block.

Fred

ChrisJ said:

Fred said:

Have you taken the LWCO probe out and cleaned it with some fine steel wool? Maybe even replace the probe. Don't use teflon tape tape on it when you put it back as it needs to ground to the boiler block. It may need to be replaced. With it switching on and off like that, it probably isn't allowing enough time for the water feeder to activate.

Sigh,
Fred, you have to use thread sealant on the probe, its NPT.
3 wraps of PTFE tape, or some pipe dope are required or it will leak.

The warnings are not to go crazy with PTFE tape or it may not ground good to the block.

I would use pipe dope but PTFE is a hit or miss, IMHO.
EDIT: My thinking here is that the OP may be having a problem with a probe that just may not be grounding so avoid the tape as a means of eliminating that possibility. I know some use tape with no problem. Most suggest dope anyway.

ChrisJ

Fred said:

ChrisJ said:

Fred said:

Have you taken the LWCO probe out and cleaned it with some fine steel wool? Maybe even replace the probe. Don't use teflon tape tape on it when you put it back as it needs to ground to the boiler block. It may need to be replaced. With it switching on and off like that, it probably isn't allowing enough time for the water feeder to activate.

Sigh,
Fred, you have to use thread sealant on the probe, its NPT.
3 wraps of PTFE tape, or some pipe dope are required or it will leak.

The warnings are not to go crazy with PTFE tape or it may not ground good to the block.

I would use pipe dope but even PTFE is a hit or miss, IMHO.

How many probes have you installed using PTFE and how many had problems?

Fred

Exactly how many have you installed besides the one on your boiler? See my Edit note on my prior post.

ChrisJ

Fred said:

Exactly how many have you installed besides the one on your boiler? See my Edit note on my prior post.

I'm not the one saying PTFE causes problems.

I see your note, and agree with it, except that I doubt 3 wraps of quality tape will cause any issue.

Fred

ChrisJ said:

Fred said:

Exactly how many have you installed besides the one on your boiler? See my Edit note on my prior post.

I'm not the one saying PTFE causes problems.

I see your note, and agree with it, except that I doubt 3 wraps of quality tape will cause any issue.

I'm not the one saying it won't cause a problem.
Just trying to help the OP.

zackwatt

Thanks for the comments everyone, I just went ahead and ordered a new LWCO. The problems just seem to be staking up with this one. For a while now it's been short-cycling the burner when in a low water scenario. Maybe it's just a malfunctioning probe, but it's a small price to pay for piece-of-mind.

The water feeder is set on LWCO and 6min delay. In my mind, there is no reason why the LWCO yellow light should be turning off until the water level is raised to an appropriate level by the feeder. The noise in the video is the relay in the LWCO, it just seems to be malfunctioning...

zackwatt

I replaced the LWCO with a new one, and all is working perfectly!

I see why it's not a bad idea to have a backup LWCO...