Sorry to say, but I have a natural gas boiler w/ 3 zones, not a wood boiler (will install an insert this summer though). But... I figure the collective knowledge here may still be able to theorize with me here. So I have a one story ranch, with three evenly spaced/sized zones, all interconnected with no way to block heat from one zone to the other: Zone 1 - Kitchen and sun room Zone 2 - Living and dining room Zone 3 - Bedrooms So which would yield a lower heating bill.... Scenario 1: Turn Zone 1 & 3 to 63F as we don't spend much time there. Turn Zone 2 to 68F as we spend the majority of time here. Pros... only heating the zone you spend the majority of time in. Cons.... maybe Zone 2 is working overtime because heat is spilling into cooler zone 1 & 3 all the time. Scenario 2: Turn Zone 1, 2, 3 to 68F. Pros... yes I am running all three zones to 68F, but once the entire house gets up to temp, the entire heating system should turn off, for awhile anyway, as the entire house cools together. Cons.... I am heating the entire house to 68F, instead of just one zone. Thoughts on what is more energy efficient?