What is the difference between a Gradient syncFURNACE and a regular furnace plus hot water tank?

Three practical differences. Space: the syncFURNACE replaces two appliances with one and Gradient says it fits in about half the footprint, which can mean a mechanical closet rather than a mechanical room. Venting: it needs one vent set instead of two, which matters in older Calgary homes with a single chimney. Modulation: it has a 10:1 or 12:1 turndown ratio, meaning it can run at 10 percent or less of capacity, where Gradient notes most conventional furnaces cannot go below about 40 percent. Lower modulation means fewer temperature swings.