Bizzarre Boiler problem

[Deleted User]

dan describes that type of system in his 'how come' book, and there may be a clue as to it's successful operation.

i'll re-read it and see if anything jumps out, but i'd also suggest that you get a copy from this site

John Stephens

Hi. My wife and I recently purchased a home in Hampton, Va, built in 1919. The house is still heated by the original gravity system that it was built with. In the late 60's, the boiler was changed out for an old federal boiler, and the expansion tank was replaced with a newer one (along with some of the piping). The problem I am having is this: The water will only circulate through the house and bring it up to temperature one time. After the system reaches it's peak temperature, the hot water will not leave the boiler again--it simply stays in the boiler and heats up until the aquastat relay cuts off the electricity to the ignitor. The only way I can get it to "reset" is by turning on the feed and building up the pressure in the system to about 10 psi. At this point the expansion tank overflows, and the water will circulate again.

I have asked many and done hours of research to figure out this problem but I just can't. Any suggestions?

Thanks

Steamhead (in transit)

Are you certain

they didn't reverse the feed and return connections when installing the boiler?

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

John Stephens

I'm sure about this, because there is no circulator, there is one main line that goes up to the attic and then feeds all of the radiators from a pipe system up there. My latest theory is that maybe there is air in the expansion tank that can't get out because the "vent" is on the bottom of the tank on the same plane with the feed. What do you think?

John Stephens

Is the description in the book anything like the description online? I've read his post a hundred times and can't find the specific information I need.

[Deleted User]

i haven't read the online

point me to it

John Stephens

http://www.heatinghelp.com/heating_howcome1.cfm

[Deleted User]

yeah, that's it

eyeball that third pic of the expansion tank layout/
sightglass-water level?/does it look like yours?, and see if you can determine if there's a clog somewhere. i'm working mostly on guesstuition, but i'd bet on a clog/
rusty debris/'vacuum' lock