Main 30HE Hot Water Fault Finding A Professional Diagnostic Guide The Main 30HE was a staple of many installs across North East Lincolnshire for years. While they are generally robust workhorses, ageing components, particularly within the Domestic Hot Water (DHW) circuit, can lead to intermittent faults that test even the most experienced engineer. At iWarm, … Continue reading Main 30HE Combi DHW Fault Finding