Oil Boilers
Oil boiler problems, fault codes, running out of oil, and OFTEC engineer guides
1 free DIY guide · 21 total
Around 1.5 million UK homes still rely on oil heating — mostly in rural areas beyond the mains gas network. Oil boilers work on similar principles to gas boilers but have some unique failure modes: running out of oil, dirty or blocked oil filters, air locks after an oil delivery, and nozzle wear that causes poor combustion. All oil boiler service and repair work must be carried out by an OFTEC-registered engineer, just as gas work requires Gas Safe registration. These guides cover Worcester Heatslave, Grant Vortex, Ideal Isar HE, and the most common oil boiler faults, plus AGA and Rayburn range cookers running on oil or solid fuel.
Grant Vortex Oil Boiler Problems — Faults & Fixes
Grant Vortex Pro or Condensing not working — lockouts and common faults
Oil Boiler Annual Service — What's Involved and Why It's Important
What happens during an oil boiler service and how often is it needed
How much does it cost to replace an oil boiler in the UK?
UK prices for oil boiler replacement, including OFTEC requirements, tank considerations, and switching to a heat pump.
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