manually adding more water-- how cold does boiler need to be?

steam_nutmegger

I tried the search as well as Google but could not find an answer to my question.

Also, excuse the lack of details regarding make/model but it is 3am here.

I have a Weil-McLain steam boiler that is about eleven years old.

The low water cutoff works but the autofill has stopped working.

So I am manually adding water either when the low water cutoff
prevents boiler start or when the glass tube gets down to 1/2"

I am filling half way up the glass tube.

My question is-- how cool does the boiler have to be before I add
water to avoid risking cracking it? I have sometimes in the last
couple of weeks added a little water about 30 mins after it shut off.

Was that too soon? When it finishes a heat cycle, and the water
is less that 1/2", should I turn off the heat and let it cool much
longer like two or three hours?

I do not need to hold the button down for long on the autofill
to bring the level back to half-- maybe for 20-30 seconds.

I am not seeing any water on the ground but want the boiler
to last as long as possible. I was hoping to continue manually
filling it the next month and then have it evaluated/fixed.

Thanks for your help!!!
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EDIT: OK I did just find this thread searching for cracking
https://forum.heatinghelp.com/discussion/164092/how-long-cool-down-before-adding-water-to-boiler

It does answer some of my questions-- but brings up a new one-- if the
boiler shuts off because the low water cutoff has turned it off, and the
low water cut off keeps clicking, but the autofill doesn't work-- is it safe
to add water right away then? Is there any water left in the boiler?

Is a margin of safety to turn down the thermostat (thereby shutting off the
boiler since the button on the autofill does not work if I turn off the
main emergency power switch to the boiler), wait 30-45 mins,
then add water, and then turn heat back up? Thanks!!!

HVACNUT

Temperature doesn't matter. The auto fill doesnt pre heat it.
What your doing is fine keeping the glass at half. There should be stampings on the boiler jacket near the gauge glass showing minimum water level.
How often do you need to manually feed?

BobC

If you have to add water very often you have a leak somewhere, look around for it at all unions, valves, and air vents. If any p[ipes go under the concrete there could be leaking you can't see. When the boiler has been steaming for a bit go outside and look at the chimney, if you see plumes of steam you might have a crack in the boiler.

Automatic feeders do so slowly, you should feed water into a boiler slowly so it does not get shocked. The pipe that feeds water into the boiler shold do it into the wet return so cold water will mix with the hat water in the return.

Bob

EBEBRATT-Ed

holding the button for 20-30 seconds will not crack the boiler.

Do find and fix the leaks or find out where the water is going