Boiler won't fire when water is shut off

ccddo

I have a plumbing issue in the house and needed to shut off the water supply to the house. My steam boiler doesn't fire with the water shut off. However, the water level in the boiler is fine. Also, the vent damper is making a noise.

Question: are these related. I'm wonder if the boiler will not fire because the water is shut off (doesn't make sense to me since they are separate systems) or if this is a coincidence and something is going on with the boiler.

Fred

If the water level in the steam boiler is OK, shutting the water off in the house will not affect the boiler operation. After all, except for the times water is being added to the boiler, the water is always off. What kind of noise is the damper making? Is it stuck/failed closed? Is the thermostat calling for heat?

ccddo

Damper is making clicking running noise - constant when thermostat calls for heat but boiler won't fire. I flipped main power a few times and the boiler fired. I'm thinking damper is failing. After some internet research, seems easy to replace. Any pitfalls to just swamping it out with a new one?

Thanks.

Fred

They're not hard to replace. Most have a manual "open" that allows you to open it and lock it open until you get the replacement.

ccddo

Thanks

Zman

I wonder if you have a miswired low water cutoff or autofill device. Could the safety switch be wired in series with the safety on the damper?
The steam guys on here would have a better idea if this is possible, It can't be a coincidence that it cuts out when the water is turned off.

JUGHNE

Do you have a back flow preventer on your boiler water feed line? This is a long shot but could it be that turning off the pressure to the boiler somehow would pull water out of the LWCO, thereby dropping the float shutting down burner circuit.
FWIW--WAG.