Condensing Boilers
Condensing boilers pull extra heat from flue gases by cooling them until water vapor condenses, which squeezes more heat from every unit of fuel. They work best with lower return water temperatures, so buildings with radiant floors or oversized radiators get the most benefit. Apartment owners, schools, and office buildings often install several modular condensing boilers instead of one large unit, adding redundancy and better turndown. When buying, plan for condensate neutralization, PVC or stainless venting, and water quality, since these heat exchangers are sensitive to debris. Most buyers choose new units for the manufacturer warranty.