Hypothetical: If boiler is cracked, and steam escapes from chimney

CoachBoilermaker

How would you know without looking at chimney? What would happen inside the house? Radiators don't get hot? Then you look up at chimney?

CoachBoilermaker

If the boiler is cracked and steam escapes from the chimney, here's what would likely happen:

1. Radiators wouldn't get hot: Since steam is escaping through the crack and not making its way into the steam pipes and radiators, they wouldn't heat up. You'd notice cold radiators despite the boiler running.
2. Boiler runs continuously: The thermostat would keep calling for heat, and the boiler would continue running, trying to generate more steam to satisfy the thermostat. But most of that steam would be lost through the crack, leading to inefficiency and prolonged operation.
3. High water consumption: The boiler would lose water faster than normal due to the steam escaping. This could cause the automatic water feeder to kick in frequently to replenish the water, or if no auto-feed is installed, you'd notice a significant drop in water levels in the sight glass.
4. Look up at chimney: After noticing cold radiators, you might suspect something wrong with the boiler. Upon inspection, you'd potentially see steam or vapor coming out of the chimney, which is unusual. This would indicate that steam is escaping from the boiler into the flue instead of circulating through the radiators.

In this scenario, you'd likely realize that there's a problem with the boiler itself, such as a crack in the heat exchanger, which is allowing steam to escape into the chimney instead of the heating system.

CoachBoilermaker

Damn, the GPT is crazy !

Jamie Hall

Oddly, depending on the size of the crack, you might get some heat. In a very well vented system running normally at very low pressure, you might not even notice that much difference in how the system heated unless you were paying attention.

What you will notice is greatly increased water use — and, of course, steam from the chimney.

KC_Jones

I heated my house from end of January 2014, until May 2014 with a hole in the cast iron.

I noticed basically zero difference in the heat from a comfort standpoint.

Water usage was way up, but it heated just fine.

SuperTech

Just flood the boiler up to the piping, that will reveal any leaks. I don't work on many steam boilers, maybe 3 or 4 every year but I worked on one yesterday. First thing I did was flood the boiler to check for leaks. The boiler itself didn't leak, but the Hartford loop began pissing from a rot hole on the horizontal nipple and the condensate return piping began leaking in several places

Mad Dog_2

Of course, it depends on size of crack/hole and the size of boiler relative to the load, but I have personally never run in to a situation where the radiators stopped getting hot. The white "smoke" flood the boiler, or a hydrostatic test of the block was how I knew. Mad Dog

EdTheHeaterMan

I should hope that @CoachBoilermaker has resolved the cracked boiler query from October 22 by now…. @SuperTech

But stranger things have happened.

Intplm.

Depending on the crack, just removing the top panel of the boiler would usually reveal the damage on top of the heat exchanger. Whether the thing heats satisfactorily depends on the system, the size of the hole, etc.

ethicalpaul

Please prefix any proclamations from AI with some kind of explanatory text such as "The statements below are from AI". I'm not sure why you have been asking questions, then immediately posting answers from AI underneath them, but maybe there's some reason!

Also, people often say "cracked" but from every picture I have ever seen on this site, it's a rusted out hole or rusted out area between sections, there is no crack.

I'm sure if a hot boiler is flooded with cold water it might crack, but I've never seen that photo on this site in the last 7 years

delcrossv

https://forum.heatinghelp.com/discussion/comment/1815778#Comment_1815778

We do get a lot of "what if's" from him.

Mad Dog_2

Actually, I've seen many more cracks on boilers than rotted through holes. Mad Dog

ethicalpaul

Thanks! Residential boilers?

Were they caused by someone adding cold water to a hot boiler?

Were they below the water line, or everywhere?

Sorry about the questions!

STEAM DOCTOR

My experiences, 99% are holes, not cracks. I only do residential