Unsolved Mystery: House Interior Found Covered in Ice

[Ryland]

A steam system like you have requires not only that all your lines be clean and that it's really turning the gallon or so of water that is in the system to steam and that it's doing so for long enough that it's reaching every radiator, I suspect that the radiators that busted open are the farthest from the boiler, or farthest from the thermostat that turns the boiler on, then they get water collecting in the bottom, as we all know evaporating water has a cooling affect, this not only makes a steam heat system work more efficiently then many other heating systems, it also mean that water that was just boiling will freeze quickly in a cold place.
Most anti-freeze solutions don't take kindly to heat over 260F, and they raise the boiling point making it harder to make the steam.

[wagonman76]

I have had a pipe burst before in the crawl space and this kind of thing worries me. Thankfully at the time I had caught it, but had I not caught it, the whole crawl space could have turned into a pool or block of ice. I also had a pipe burst below the sink. Something I have done to keep any more pipes from bursting is to turn my water inlet valve so it is only open 3/4 turn, which still gives decent water pressure. Opened all the way and taking a shower is like driving nails into my back. I am on a community water supply at the bottom of a hill. The water main in my front yard has blown 3 times in the 10 years I have lived here.

One thing I have thought of doing is put a solenoid valve at my water inlet, and connect it to a humidity alarm so it cuts the water when the humidity gets to a certain point. One thing I noticed was the extreme humidity under the house when the pipe had blown, much more than any muggy summer day.

[aerohead]

A guess.The system malfunctions,the house loses heat.Residual moisture condenses and collects in a few of the radiators and fails to drain off.As temperatures fall below freezing temperature inside the house,the water condensate freezes,expands,and ruptures the few radiators.At some point,the system controls sense the ambient house temp and attempts to satify the setback temp setting.The boiler fires,steam emanates from the breach in the shattered radiators,the 100% relative humidity air freezes on the sub-freezing temperature inside surfaces,coating the inside of the house with ice.------------------------- At some point,the logic of the controls "works",and opens a circuit to protect against the malfunction it's just now sensing.Without repairs and a reset from the HVAC technician,the system remains off,maintaining the freezing temps until discovered.