air pocket

Alex_5

I have a project installed with copper fin tube boiler. I have circulation pump maintaining sufficient flow already but the heat exchanger tube is dropping down slowly. I am wondering why, could the air in water be a problem? because no seperator installed yet. Any help is appreciated!

Mark Eatherton1

SHUT IT DOWN!!!

You said "the heat exchanger tube is dropping down slowly."

If your heat exchanger tube is drooping, there is no water in it to cool it down, and you're about to experience a boiler melt down. Your warranty (if any) is already VOID.

Sorry for the bad news.

ME

Alex_5

I have to know what the other cause is and so I can correct it. I doubt the air bubble is making the trouble. want to know other opinion.

Mark Eatherton1

If you get no flow...

and you have no air eliminator, it's a 98% chance that its an air problem. And it's probably not in the same room as the symptoms.

You evidently don't have a flow switch on the circuit, because IF you did, and it detected that there was NO FLOW, it wouldn't have allowed the the boiler to FIRE.

The best suggestion I can make is that you READ the installation instructions and make darned sure that the installation complies to the T. If you're not comfortable doing this, then I'd strongly suggest you contact a licensed contractor who is. You're messing with dynamite here, NO KIDDING.

ME

Mark Eatherton1

Just in case you think I'm kidding...

Heres what your boiler will look like if you continue to run it. This family nearly died from CO poisoning from this boiler. The heat exchanger was leaking enough water onto the burner to the point that is was rolling out of the combustion chamber.

Dynamite....

ME

Alex_5

Thanks! I think you are right. I have flow switch in place. The flow is sufficient by the right temperature rise according to installation manual. so I am wondering that air bubbles or too much suspended solid in water causing heat transfer difficulty and superheated copper tube and so it sags.

Weezbo

Did i not post something to you the other day?

maybe i didnt...my thought was to repurge the system.now it days later..the horse probably broke its leg....you really need to purge the air out of systems first.you can fill and valve a boiler to get some hotter water to make sure it circulates back around once the zone iz purged and filled.however, Mark is telling you the truth with those pictures....

Mark Eatherton1

TDS will kill a boiler too...

but not just from inital fill. You'd have to have a leak someplace in the systems in order to expose the hot heat exchanger to the required amount of TDS to cause it to plug, and then melt down. THat's exactly what happened to the boiler pictured. It was the HO's THIRD boiler. Origial contractor replaced HX once, and service company replaced it once after that, and a complete boiler once after that, all in a span of 4 years! You'd have thought that someone some where would have eventually caught on. The HO called us out of desperation and a referal from a cast iron boiler rep. After talking to him for 5 minutes, I told him he had a leak in his system and that he needed to find it and fix it or he'd be buying another boiler in the near future..

The leak was in a 3/4" line directly in front of his bathroom vanity. It dawned on him when he was standing there brushing his teeth...

If you have enough water going into your system to cause a tube to plug and melt, you need to find it quickly, and its probably not going to be easy. Is house slab on grade? Or basement with concrete floors.

ME

Gordy

Wowzee !

Where was that boiler? Out behind the barn where no one could see,smell or hear anything. Truley amazing! How could that be in someones home and not know something is up. A while ago.

Lou Chiavetta

Steam Heating

School at IHM Church in Scarsdale. I am a parishoner there and a PE and was asked to help in determining why classrooms are not getting full heating i.e.some radiators are half hot and some cold. I determined that condensate is being trapped inside. The traps at the radiators had been replaced about a year or two ago.I had the plumber who did the work return and we checked some of them and they were O.K. The system is a two pipe system. We traced the pipng through the building down to the boilers. The boilers are Kiwanee's vintage 1923-26 and, to anyone's knowledge, have not had much maintenance. Located at the top of the return line feeding condensate to the boilers are two vessels,piped together and also of old vintage. One is probably a trap and the other(?). The school has a maintenance contract and has called in the contractor. He believes that the problem lays with this trap. He tracked down the company but they do not make this trap any longer. The contractor is trying to find parts, with the help of this company,to try to re-build it. Before this trap there is a drain line and valve. We tried to drain some of the condensate but only get a small flow and trickle. The plan is to get this solved until Spring, at which time we intend to get a new boiler.The children must have some heat in the event of a cold winter.
There are no drawings or schematics of the existing system that can help us.This is a very old system from what I can determine. Do you have any ideas as to help us with this problem?

Joannie_4

And....

Just another thought.....Make sure you are putting the correct minimum water temperature into the unit. If you get condensation on the outside of the copper heat exchanger, it can plug up the fins and that can overheat more than just the heat exchanger. If you can see the copper tubes drooping, you'll be able to see if they are clogged, as well.