Oil Boiler Services
Oil Boiler Services Done Right
Cosy, dependable heating that uses fuel efficiently and keeps breakdowns to a minimum — that’s the outcome we aim for. Sigma’s Navien oil boiler services cover full installations, annual servicing and rapid repairs, all carried out by engineers experienced with oil‑fired systems and Navien products. Based in Milford Haven, Simon knows local building types from coastal cottages to modern semis, so diagnostics are faster and more accurate. We register manufacturer warranties, complete factory commissioning and prioritise safety and clear communication throughout the job.
Why Choose us for Oil Boiler Services?
Approved experience with Navien oil products means installations and repairs meet manufacturer standards and qualify for factory-backed cover.
How It Works
Survey & Honest Quote
We inspect the boiler, flue and fuel supply, explain options in plain English and provide a clear, written quote before any work starts.
Safe Installation or Service
For installs we follow factory commissioning and warranty registration; for servicing we carry out burner clean, flue check and performance tuning.
Handover & Ongoing Support
You get a service sheet and manufacturer paperwork. We offer 24/7 emergency response and will register warranties where applicable.
Frequently Asked Questions
Find answers to common questions about our services and process.
We recommend an annual service to keep efficiency high and reduce risk of breakdowns. Annual checks include burner clean, flue inspection and performance tuning; regular servicing also helps protect any manufacturer warranty.