condensation on boiler...normal?

92civeg

Hello all

I recently purchased a home with radiant heat, last winter the boiler gave me no trouble but i never noticed this condensation. I lit the pilot on it today and noticed that there was condensation on one side that beaded up and lasted for about 10 min then went away. I had a company come out to take a look and they shut it down and said i needed to buy a new boiler beacuse it has a "water leak". I spoke to a few other companies over the phone and they explained the condensation is normal and the company that came out just wanted the "sale"

I fired it back up and have had it on all day and its dry as a bone until the boiler fires up then the condensation will last ten min then dry out,can it just be the temperature change causing the condensation or do you really think its leaking?

the boiler is a slant fin 100 series

I hope you can see the condensation in the first picture, thank you for any advice you can give!

92civeg

i should add that the boiler held 18psi all summer and never leaked a drop...here is a photo of the boiler anyone have an idea of the age of it?

Jamie Hall

Without looking at it in person, it's a bit of a shot in the dark. However, if the sparkles I'm seeing are the condensation to which you are referring, it's most likely water condensing on the cold boiler from the combustion gasses from the burner.

That's not a boiler leak. However, it does suggest that perhaps the draught is not what it should be, as the combustion gas really should go up through the boiler sections and out the stack.

First thing I'd do is get a competent tech out there -- not the chap who wants to sell boilers -- and make sure that the boiler is properly cleaned and adjusted.

Then see what happens...

delta T

Agree with Jamie, that is an odd place for condensation to for. Use the find a contractor link on here and find someone close to you to do an inspection and tune up.

What kind of radiation is this hooked up to? You say radiant heat, does that mean cast iron radiators, panel radiators, radiant floors, what?
Mostly looking for what temperature the system runs at normally.

hot_rod

Consider investing in a CO, carbon monoxide detector for your home also.

92civeg

It's heating cast iron radiators, the temp in the basement is about 50-60 degrees, and water temp gauge on the boiler reads about 140 when it's running.

JStar

Condensation will form on the inside openings of the boiler, not the outside. It may be a small leak that seals itself after expanding. It could also be a little bit of exhaust roll-out on start-up.

delta T

Hard to say without being there, but if that condensation persists for 10 minutes, I don't think its just an ignition roll-out, Picture does not seem to indicate a leak, but looks much more like condensation to me.

I second Hot rod's recommendation, you should definitely have a CO alarm. That is something I strongly urge anyone to get regardless of the age or condition of their system.

Something seems to be wrong with the way the boiler is drafting. Get someone out there who has a draft gauge and combustion analyzer and they can tell what is going on. Where are you located?

92civeg

I'm in St. Louis missouri

hot_rod

The service person should inspect the entire flue system, where does it terminate on the roof, any changes over the years that might change draft conditions? Building addition, trees?

The discoloration on top could indicate either extended cold runs, draft issues, or just age, all are worth investigating.

If it is oversized for the load, especially with all the mild weather, it could be short cycling and not getting up to a good temperature before shutting down. A load calc is always good.

Quite a list of to-dos. Let me know if you need some suggestions for a knowledgable contractor, we have a rep in that area that has many connections.

delta T

Not in my neck of the woods at all (Colorado), and nothing comes up for St. Louis.

The contractor you find needs to be able to actually check the draft using a draft gauge, needs to have a combustion analyzer to check for proper combustion and needs to be familiar with and regularly work on hydronic heating systems. Other than that I am not sure what else to tell you.

A draft problem (which is still a guess btw, can't say for sure without being there myself) can be caused by any number of things such as insufficient make up air to the room, horizontal run on the venting being too long or improperly pitched, blockage in the heat exchanger, blockage in the flue, combustion issues, and the list goes on.