Weil Mclain Ultra Boiler, E 02 error and water coming from silencer

TD3202

We have an Weil Mclain Ultra 105, series 2, that gives intermittent E 02 failed ignition lockout errors. The error can usually be cleared and the boiler started up with a reset.

This error occurs mainly when it's very cold outside -- I think it's only happened a couple of times when the temperature was above 10 or 15 F.

After one of the lockouts, I took off the front cover to have a look inside. I noticed a small pool of water (probably a couple of tablespoons?) on the bottom of the boiler. I checked to see if there was leak in condensate line or heat exchanger, but those both appeared fine. It turns out the water was dripping from the air intake silencer, and when I gave the silencer a shake some additional water ran out of it. I've opened the cabinet a couple more times when the boiler was starting normally and the water was absent.

A couple posts on this site seem to suggest that liquid condensate accumulating inside the combustion chamber and turning to steam could be the source of this moisture. The most recent full maintenance & cleaning of the boiler was in March 2021. I have recently had a look inside the condensate drain fitting and at the trap. Both are clean, and condensate seems to be flowing fine through the drain line.

Another possibility based on Ultra boiler posts on this site would seem to beand water from the system entering the combustion area from a cracked heat exchanger. We have to add water to the system manually, and it is rarely ever necessary to do so, but I don't know the rate at which water would be lost from a cracked heat exchanger. How is a cracked heat exchanger diagnosed?

Before we have someone out to look at this, I want to ask a couple of questions here in case anyone has any insight regarding this issue:

-Basically, water dripping from the silencer doesn't seem like it would be a normal situation with this boiler. Could the 02 errors be related to the presence of so much water in the silencer, and possibly in places upstream from the silencer?

-If this water accumulation could be leading to the ignition errors, what is the most likely cause, and how might it be fixed?

-In composting this post I've come to think the presence of water and the ignition error must be related, but if they are not, what other factors might cause ignition failure to occur only when environmental temperatures are low?

Thanks in advance for any guidance on this.

HVACNUT

Where is combustion air coming from? Is it piped to outside or pulling from the space?
Have you removed the drain hose from the bottom of the heat exchanger? Be careful. When the blocks leak, that's where they typically leak from. If you pull the drain hose and Niagara Falls pours out, it's a clogged drain.
If you pull the silencer off, is there water at the fan? That won't be good.

TD3202

The combustion air comes from outdoors via a 3 inch pipe. It's a short run with only a couple of elbows.

I did disconnect the drain hose to check whether anything was clogging the drain opening (stuck my finger up there to feel around). No water came out from the heat exchanger itself, just a bit of spillage from the trap hose.

I haven't removed the silencer, I can try to see what things look like there. It's in an awkward location behind the gas supply pipe etc., I don't know if I'll be able to see much.

HVACNUT

How far away is the exhaust from the intake outside? Any chance exhaust gas is being pulled back through the intake?

Tim_D

That is a very odd issue. I would be looking for flue gas recirculation.

kcopp

I looked at a Weil Ultra series 2 boiler today...
Ser 2.
Sporadic E05 error.
I also noticed a drip from the fan and the silencer.
here is the odd part. The cover has been off for a good amount of time (months)
Flue gas recirc is prob not a factor. Terminations are pretty far apart. Longer runs 15 feet each.

HVACNUT

kcopp said:

I looked at a Weil Ultra series 2 boiler today... Ser 2. Sporadic E05 error. I also noticed a drip from the fan and the silencer. here is the odd part. The cover has been off for a good amount of time (months) Flue gas recirc is prob not a factor. Terminations are pretty far apart. Longer runs 15 feet each.

An 05 hard lockout on the Series 2 is an internal control or display error. You say its sporadic so maybe just the ribbon cable.

kcopp

I saw that. Thanks.
The strange coincidence was that i had also observed the same dripping the OP had seen.

TD3202

Regarding the possibility of exhaust gas recirculation: Would this be taking place outdoors? The intake and exhaust are via a sidewall termination plate that I think was supplied with the boiler. I've attached a photo of the plate and its location.

kcopp

I would say that is certainly a contributing factor. That is a concentric vent termination. I am not a fan of them. They are prone to recirculation issues in my opinion. Yes it came w the boiler still think they are a poor termination.
The fence (w/ plants growing into it) on one side as well as the chimney on the other and the distance off the ground does not help.

JUGHNE

You have nearly a double inside corner.

Great looking old school stucco though. I assume it is old, thrown on, finish coat.
Almost not available any more.

TD3202

Thanks to all for the input. Recirculation seems like a good possibility. I'm going to replace the termination fixture with a snorkel arrangement that will separate the intake and vent, as well as get both higher above the ground/snow line. I've got the sidewall venting requirements from Weil Mclain and will follow those.

Buckwheat

Simple check… the condensate hose inside the boiler that runs along the bottom.  That fills up with sediment and restricts flow.  Disconnect it and tip it and run clean water through it. It can be hard to see just how much sediment had built up.