Weil‑McLain 386701013 Gold S4 Packaged 3‑Section Oil‑Fired Water Boiler (86% AFUE, 133,000 BTU, Natural Draft)
A fully assembled three‑section cast‑iron oil boiler designed for long‑term reliability, quiet operation, and efficient hydronic heating. The Gold S4 series is known for its rugged cast‑iron heat exchanger, simplified service layout, and consistent performance across a wide range of residential applications. This packaged model includes a factory‑installed oil burner and is configured for natural‑draft chimney venting, making it an ideal replacement for older atmospheric oil boilers.
Key Features
Three‑section cast‑iron heat exchanger engineered for even heat transfer, thermal stability, and long service life.
Factory‑installed oil burner matched to the boiler’s firing rate for clean, stable combustion.
133,000 BTU heating capacity suitable for medium‑to‑large residential heating loads.
86% AFUE efficiency delivering dependable performance with straightforward maintenance.
Natural‑draft chimney venting for easy replacement of older oil boilers without venting modifications.
Service‑friendly design with accessible burner, controls, and piping connections for faster annual maintenance.
Quiet operation supported by Weil‑McLain’s combustion chamber and cast‑iron block design.
Ideal Applications
A durable, packaged oil boiler for homes with existing chimney venting that need a reliable, mid‑capacity hydronic heating system with a factory‑matched burner.
