No circulator?

Jimbo_5

I have a 25-year old CG-3 WM, and tonight I noticed that the circulator is not running.  It has a 10-year old B&G 100 on it, and it feeds the apartment directly overhead, a loop of fin-tube, say 50 feet out and back.  I can hear the boiler fire and run, the supply pipe gets good and hot, and I stood next to it listening carefully.  But I did not hear it come to life--usually it is quite noticeable.  Then slowly after a good amount of time, the return side started to warm and get hot.  Is this possible with out the circulator working?  It's driving me crazy. 

Dylan Thomas

Gravity

I think the circulator may be dead.  If the return is slowly warming you may just be watching gravity at work.  Hot water rises and the cold water sinks back down to the boiler.  An old house I used to live in had a gravity system with no circulator and it was amazing how well that works. 

Dylan Thomas

Have it checked out

That said, the circulator may be fine and there maybe be some other fault that has cut power to the circulator.  Definitely check with the pros here for advice on troubleshooting the circ.  It could be a bad controller or relay instead.

EricAune

Not designed for gravity

I would have to guess your system is not designed for gravity and will not operate properly without a circulator.  Just a guess, but likely the case. 



Have a pro check out the pump.  Operation in this mode will certainly consume too much fuel, be uncomfortable and could definitely cause property damage by way of a flashed boiler or water spilled from the relief valve.

Jimbo_5

Thank You

I agree, something is definitely wrong.  The last one I had was a bit easier to tell there was a problem.  It would try to start, noticeably shifting in its mounts, but sounded bound-up.  There was a sludge-like substance in the impeller, which I guess froze the motor.  Where this sludge came from I cannot imagine.  Is that common?