Installing a boiler is a popular solution when looking to put in a new house heating system or upgrade an old one. On average, installing a boiler costs $4,500 – 8,000 depending on the type of boiler you select, including professional labor and the device itself. Boiler Replacement Cost Standard gas or oil boilers, without a tankless or indirect hot water feature, will usually have 82-86% AFUE efficiency rating and will cost $4,690 – $7,200 to install (oil boiler being about $500 more expensive than gas, as it needs an Oil Burner – an expensive part, which is not needed… Read more »