Weil-Mclain Ultra 155 Kettling Issue

LynnT

I have a Series 3 boiler installed 12/2009. The heat exchanger developed a leak and was replaced under warranty 02/2018. The boiler heats domestic hat water, some in-floor heat and a forced-air heat exchanger. The issue I'm having with it started over a year ago. Now, it is working fine but the boiling sounds coming from inside the heat exchanger have got me wondering. You can hear it thru the floor in the kitchen above the boiler. High limit's 190, same as always been. I had one tech out who didn't have much of an idea what it was. I haven't called W/M, not sure they'd be interested in diagnosing it. Who has ideas?

HVACNUT

When was the last time it was cleaned with the maintenance kit?
When was the last time combustion was tested?
Has the inhibitor level been tested? It's an aluminum block and you went through one already. 
Does the tridicator work? What's the pressure on the boiler?
Is it draing properly?

I don't see system supply and return sensors. 
Are those Tee's 12 inches or less apart?
Pretty weird piping layout but I don't think that's the issue.
No auto reset codes in history?

hot_rod

They take a hit on the inside from water quality, and on the combustion side from whatever they inhale.

kcopp

Why is it running so hot? I would turn down the high limit to 175 and see if that helps.

LynnT

Thanks for the comments, I appreciate it along with probably guys reading them 5 years from now!
The original Glowcore boiler was less temperamental than this W/M. I have to manually reset it about once a year.
The set temp on zone 1 fan coil is 180, per the book. The city water is pretty good here in the upper midwest. I replaced the floor heat manifold recently and exchanged all the internal water at least twice, it's crystal now. It was rusty in the floor tubing, I think from the pump, which was disconnected. It did clear in 10 gallons. I had to use adapters and convert the 32 yr old red 3/8" PB tube to 3/8" PEX, since new manifold is not rated for PB.

HVACNUT: Thanks for the detailed comments! The boiler got a maintenance kit, scrubbed out and electrode 6 months ago. Combustion and inhibitor tests.....never. The block had a known flaw, susceptible to acid exhaust, that's cured with the new design. Tridicator works, 15 psi. T's are 12", yes. Condensate drains fine. Not sure why I don't have supply and return temp sensors. I do have a tube of Sentinel X-100 inhibitor that could go in now.

I'll see if I can attach a video and you can hear it run.

LynnT

Best I can do is this link to the video I took yesterday.


https://youtube.com/shorts/8VwwnowgFSQ?feature=share

LynnT

Here is video at YouTube.

https://youtube.com/shorts/q3HlcElTHSo?feature=share

HVACNUT

It doesn't sound like kettling, it sounds like a circulator bearing assembly. 
In the first video, the noise is continuous. In the second video it seems to stop.

Do the screwdriver to ear test and listen at at the boiler circulator (0014?). Even though it's not quite 3 years old, it could be bad.
Do you have a way to check amps on it?
No glycol?

Yes, add the inhibitor. A test pack should've come with the maintenance kit. 

Nothing in error history?

LynnT

I think you're right, it's the pump not the boiler. When the water storage tank calls for heat the red pump runs and there are no boiling sounds. I'm going to monitor it for now, thanks for suggestions!

HVACNUT

LynnT said:

I think you're right, it's the pump not the boiler. When the water storage tank calls for heat the red pump runs and there are no boiling sounds. I'm going to monitor it for now, thanks for suggestions!

Don't monitor for too long. It's got isolation valves so replacement is less than a half hour. Then run and check all zones.
I can't see exactly what circulator that is. Just make sure it's the exact replacement as detailed in the manual. I don't see a flo valve on the supply piping so I'm assuming the circulator has an IFC (Internal Flow Check).