New to the forums, so far I've seen some good information going around, so I thought I'd get ideas from everyone. I have a Crown Cayman propane boiler, with tankless coil for domestic. In addition to this system I have a Woodmaster 4400 outdoor wood boiler which basically "preheats" the water entering the Crown unit. The Woodmaster system enters the home and goes through a plate to plate heat exchanger which circulates to the Crown unit as an additional zone, utilizing a Taco 0011 circulator. The house consists of 7 zones, 2 of which are in slab radiant, one never is turned on (basement) and the other is currently set low (45 degrees) in a garage using a standard digital thermostat (air temp). Two zones are radiant under hardwood and tile, both also on digital thermostats. The other three zones are second story heating, all on baseboard. The hi and lo settings on the Crown are set to 150 and 140 respectively, as I am trying to keep the gas unit from firing as much as possible. The unit still does fire more often than I like, which is why I'm here, looking for advice on how to make this system more efficient. I'm glad to give more info if needed! Thanks in advance for the help!