I have a forced hot water system with an oil furnace. 3 zones, each with a Taco zone valve and a Nest thermostat.
The odd behavior is that when a zone gets turned off, the valve closes, but then for a period of 1-2 minutes the dial on the zone valve cycles open and closed seemingly with a mind of its own. Sometimes halfway, sometimes all the way resulting in the furnace to kick back on for a fraction of a second. Once it finally decides to settle, it often stops halfway open/closed.
This only seems to happen when a zone is getting turned off
, as opposed to when a zone is called on.
Anyone have an idea of what's causing this? Does it sound like an issue with the thermostat(s), the furnace, or the valves themselves? Here's
a video that shows what's going on (disregard the noises of baby & wife playing in the background).
Thanks for any thoughts.