The S4 replaces the FHG with an upgraded control panel and lengthened combustion zone further reducing emissions whilst enabling a longer service life. As well as offering the high quality and high efficiency standards that are expected from all Froling products the S4 also includes an optional automatic ignition device.

The S3 is a new boiler which offers a simplified control system whilst maintaining the high temperature combustion chamber and Froling's build quality. This offers a high quality log boiler for a very competitive price.