Boiler not firing up for 2nd zone, only 1st zone

[bjferri]

The circulating pump is working for the 2nd zone, so why doesn't the flue damper open and burner ignite?

One thing may have contributed...the water was shut off for the 2nd zone while it/pump/thermostat was on. It wasn't until the pump was making a strange noise that I noticed but subsided when the water was turned back on and water flowing through the system. So I can hear the water circulating but the boiler doesn't ignite.

How do I troubleshoot this?

Thanks.

[jadnashua]

Depending on how the system is configured, the boiler may not automatically come on with the circulator. It depends on the low set point. If the water is hot enough, the boiler only starts when it eventually cools off by being circulated through the heating looop(s). The low set point is often adjustable, so you could have something like 180/160, where the boiler would turn on to 180 then turn off and not turn back on again until it reached 160.

[bjferri]

Jim,

It does appear to be working the way you explained. I think it may be working correctly but I was worried I burned the circulating pump motor out.

Question: Could I have reduced the performance of the pump? Maybe not pumping as fast as it was? After all, I did have the water shut off to that pump while it was running. It just seems like the 2nd zone radiators take longer now to heat up.

[jadnashua]

The bearings in those pumps are lubricated with the water going through, so, if it was truly dry, at the minimum, you've probably shortened its life. Depends on how long it ran, and if there was any water in there at all.

[bjferri]

thanks again...