Combi boilers merge space and water heating into one appliance, providing a space-saving and highly efficient choice to fit your everyday needs. State's industry-leading ProLine^® XE Combi Boilers are easy to install and operate, offering hot water delivery and up to 74% more space heating capacity than comparable combination boilers to make sure that daily life in your home is comfortable.

Although combi and traditional boilers can both heat your home and your water, there are key differences between the two.

Designed intentionally for space heating, traditional boilers use hot water circulated through radiators or a hydronic heating system to increase the temperature of the air. A traditional boiler's water can also be used for domestic water heating when paired with a separate indirect water heater. While some traditional boilers are compatible with potable water, others need additional water treatment.

Combi boilers, on the other hand, accomplish both space and water heating with a single appliance very efficiently. Similar to a tankless water heater, a combi boiler provides continuous hot water on-demand and can switch between water and space heating with ease and dependability to ensure your comfort.

Because they are very efficient for both of their uses, space and water heating, using a combination boiler may lead to reduced home energy costs.

Yes! With a 95% AFUE rating, combi boilers are ENERGY STAR^® Certified.

State's combi boiler units enable you to have two high efficiency appliances combined as one to provide both space and water heating. With a modulating combustion system with 10:1 turndown, the ProLine^® XE Combi Boiler also works hard to ensure high efficiency operation even when heating demands aren't as high.