Job Title: In-House Mechanical Engineer – Critical site Location: Hatfield, Hertfordshire Hours: Split days pattern, 6-2 and 12 – 8 Salary: £46k + Overtime + Benefits The Role: A well-established organisation are currently recruiting an In-House Mechanical Engineer to support a large-scale, critical operational site within the Facilities Management sector. The role is based on a large Mixed use site housing a warehouse and large distribution centre, where mechanical reliability is essential to daily operations. This position sits within a close-knit in-house engineering team, offering real ownership of plant, systems, and site performance. The successful candidate will be trusted to maintain key mechanical services and respond effectively to issues in a fast-moving, business-critical environment. Key Responsibilities: Deliver planned preventive maintenance (PPM) and reactive maintenance across all mechanical building services. Maintain and fault-find systems including HVAC plant, pumps, pipework, valves, and domestic water systems. Support critical infrastructure to ensure operational continuity across warehouse and distribution functions. Ensure all works are carried out in line with health and safety legislation, site standards, and statutory compliance. Maintain accurate logbooks, reports, and maintenance documentation. Work collaboratively with the wider engineerin...