--- title: "OFTEC Oil Boiler Engineer in Northants & Rutland | Reactive" description: "OFTEC-registered oil boiler installation, repair and servicing across Corby, Oundle, Oakham & rural Northants. Worcester, Grant, Firebird & Warmflow." lang: en-GB json-ld: | [ { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "Do I need a different engineer for oil vs gas?", "acceptedAnswer": { "@type": "Answer", "text": "Yes — oil boiler work legally requires OFTEC technician registration; gas requires Gas Safe; LPG requires Gas Safe with LPG endorsement. Our engineers hold all three. Most engineers hold only one." } }, { "@type": "Question", "name": "How often should I service an oil boiler?", "acceptedAnswer": { "@type": "Answer", "text": "Annually, ideally before winter. The nozzle is a wear part replaced at every service; skipping a year almost guarantees first-frost lockouts. We send a reminder before due date." } }, { "@type": "Question", "name": "Are modern oil boilers efficient?", "acceptedAnswer": { "@type": "Answer", "text": "Yes — typically 92–94% ErP rated, comparable to a modern gas combi. Old non-condensing oil boilers (pre-2007) are 70–75% — replacing one will pay back the install in 4–6 winters of fuel saving." } }, { "@type": "Question", "name": "Can I replace my oil tank myself?", "acceptedAnswer": { "@type": "Answer", "text": "No — bunded tank installation, decommissioning of the old tank, fire valve and supply line all require OFTEC certification under the Building Regulations and OFTEC technical book. Environmental contamination penalties for botched DIY are significant." } }, { "@type": "Question", "name": "What's diesel bug and how do I avoid it?", "acceptedAnswer": { "@type": "Answer", "text": "Bacterial growth in the kerosene caused by water ingress into the tank — it clogs filters and starves the burner. Avoid by keeping the tank lid sealed, replacing rotted seals, and topping up rather than running near-empty (sediment lives at the bottom). We can polish tanks where contamination is found." } }, { "@type": "Question", "name": "Will you work on my Aga or oil cooker?", "acceptedAnswer": { "@type": "Answer", "text": "Aga and Rayburn-style oil cookers we can service if they're a standard OFTEC-recognised model. Specialist heritage units sometimes need a brand specialist — we'll tell you straight either way." } }, { "@type": "Question", "name": "Do you do tank-to-boiler line replacements?", "acceptedAnswer": { "@type": "Answer", "text": "Yes — copper line, fire valve, filter swap. Often part of a full install but available as a standalone job too." } }, { "@type": "Question", "name": "Is the work guaranteed?", "acceptedAnswer": { "@type": "Answer", "text": "12-month workmanship guarantee on all installs and repairs. Manufacturer warranty (typically 5–10 years) on new boilers, registered on your behalf at install." } } ] }, { "@context": "https://schema.org", "@type": "Service", "@id": "https://reactiveplumbing.co.uk/oil-boiler-engineer#service", "name": "OFTEC Oil Boiler Engineer in Northants & Rutland", "serviceType": "OFTEC Oil Boiler Engineer in Northants & Rutland", "description": "OFTEC-registered oil boiler installation, repair and servicing across Corby, Oundle, Oakham & rural Northants. Worcester, Grant, Firebird & Warmflow.", "url": "https://reactiveplumbing.co.uk/oil-boiler-engineer", "provider": { "@id": "https://reactiveplumbing.co.uk/#localbusiness" }, "areaServed": [ { "@type": "City", "name": "Corby" }, { "@type": "City", "name": "Kettering" }, { "@type": "City", "name": "Desborough" }, { "@type": "City", "name": "Rothwell" }, { "@type": "City", "name": "Oundle" }, { "@type": "City", "name": "Market Harborough" }, { "@type": "City", "name": "Wellingborough" }, { "@type": "City", "name": "Oakham" }, { "@type": "City", "name": "Stamford" }, { "@type": "City", "name": "Peterborough" } ], "offers": [ { "@type": "Offer", "name": "Annual oil boiler service", "priceCurrency": "GBP", "priceSpecification": { "@type": "PriceSpecification", "price": "Fixed price", "priceCurrency": "GBP" }, "description": "Burner strip, nozzle + filter swap, electrode reset, smoke and combustion test, OFTEC service record." }, { "@type": "Offer", "name": "Oil boiler installation", "priceCurrency": "GBP", "priceSpecification": { "@type": "PriceSpecification", "price": "Fixed price", "priceCurrency": "GBP" }, "description": "Worcester / Grant / Firebird condensing boiler, full install, system flush, MagnaClean, registered warranty — quoted after free survey." }, { "@type": "Offer", "name": "Oil tank replacement", "priceCurrency": "GBP", "priceSpecification": { "@type": "PriceSpecification", "price": "Fixed price", "priceCurrency": "GBP" }, "description": "Decommission old tank, new bunded plastic or steel tank, supply line, fire valve, commissioning." } ] }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://reactiveplumbing.co.uk" }, { "@type": "ListItem", "position": 2, "name": "Heating & Gas Services", "item": "https://reactiveplumbing.co.uk/heating-gas-services" }, { "@type": "ListItem", "position": 3, "name": "OFTEC Oil Boiler Engineer in Northants & Rutland", "item": "https://reactiveplumbing.co.uk/oil-boiler-engineer" } ] }, { "@context": "https://schema.org", "@type": "Person", "name": "Carl Eddershaw", "jobTitle": "Director & Lead Engineer", "worksFor": { "@id": "https://reactiveplumbing.co.uk/#localbusiness" }, "knowsAbout": [ "OFTEC Registered Technician (OFT10-105E, OFT10-101, OFT-T100)", "Gas Safe Registered", "Worcester Heatslave trained", "Grant Vortex trained", "Free oil-grade CO alarm with install" ] } ] --- Gas Safe Registered · OFTEC Registered · Checkatrade Verified 9 Rutherford Court, Corby NN17 4SJ [info@reactiveph.co.uk](mailto:info@reactiveph.co.uk) [![Reactive Gas Heating & Plumbing logo](/__l5e/assets-v1/51d713a4-18a4-4b5f-96fb-2fcce169e56c/reactive-logo.png)](/) ServicesAreasGuides[About](/about)[Our Work](/our-work)[Plans](/maintenance-plans)[Reviews](/reviews)[Contact](/contact) [24/7 Call 07915 906262 ](tel:+447915906262)[Fixed Boiler Quote](/boiler-quote) 1. [Home](/) 2. [Heating & Gas Services](/heating-gas-services) 3. OFTEC Oil Boiler Engineer Heating & Gas Services # OFTEC Oil Boiler Engineerinstallation, service & repair for off-mains Northants & Rutland Off-mains heating in rural Northants often means oil — and oil boilers need an OFTEC-registered engineer, not a Gas Safe one. We install, service and repair Worcester, Grant, Firebird and Warmflow oil boilers across our rural patch. [Enquire Now](/contact) [Call 07915 906262](tel:+447915906262) - OFTEC Registered Technician - All major oil boiler brands - Tank-to-boiler full system - 12-month workmanship guarantee OFTEC Certified technician All brands Worcester, Grant, Firebird... Fixed Annual service price 12 mo Workmanship guarantee Oil boiler — installation, servicing, repair, tank work ## OFTEC-registered oil work — different ticket, different process Oil-fired central heating is the second most common off-grid heating fuel in our patch after LPG — particularly in stone-built villages around Oundle, Oakham, and the Welland Valley where mains gas was never run. Oil boilers are a different beast from gas: pressure-jet burners with electrode ignition, replaceable nozzles, and a whole separate certification body — OFTEC. Working on oil boilers legally requires OFTEC technician registration (OFT10-105E for service, OFT10-101 for installation, OFT-T100 for tank work). It's not interchangeable with Gas Safe. Our engineers hold the relevant OFTEC tickets alongside his Gas Safe and LPG endorsements — meaning the same engineer covers your gas, LPG and oil work without juggling contractors. Modern oil boilers (Worcester Greenstar Heatslave, Grant Vortex, Firebird Envirogreen, Warmflow Agentis) are condensing, around 92% efficient, and run on standard kerosene heating oil (28-second). They're reliable when serviced annually — and disastrous when neglected, because dirty nozzles, weak ignition and tank contamination compound fast. What happens if you wait ## Skipped oil services don't fail gracefully — they fail at -3°C in January An oil boiler that hasn't been serviced for 18 months will usually start with a few nuisance lockouts — symptoms of a clogged nozzle or worn electrodes — before refusing to ignite at all. The pattern is classic: it works fine through summer, struggles in autumn, and won't fire on the first hard frost. Tank-side problems are the silent killer. Water ingress into a poorly-sealed tank breeds bacteria in the oil (the dreaded 'diesel bug'), which clogs filters and starves the boiler. Plastic tanks crack with UV exposure. Steel tanks corrode from the inside. None of it is visible until the boiler stops. - Skipped annual service → clogged nozzle → first-frost no-fire - Water in tank → bacterial growth → blocked filters → starved boiler - Cracked plastic tank → environmental contamination → major remediation cost - Worn electrodes → weak ignition → soot in heat exchanger → CO risk - Wrong nozzle size on replacement → wrong burn rate → wasted oil + soot - Non-OFTEC engineer working on oil — illegal and warranty-voiding Our process ## From first call to job done — exactly what to expect 1. 01 ### Tank & supply check Tank condition, supply line, fire valve, filter inspected. We start at the tank, not at the boiler. 2. 02 ### Burner strip & rebuild Burner removed, nozzle replaced (annual service item), electrodes set to manufacturer gap, fan and pump checked. 3. 03 ### Combustion test Smoke number test (Bacharach scale), CO/CO2 analysis, flue temperature. To OFTEC technical books. 4. 04 ### System check System pressure, expansion vessel, controls, F&E tank where applicable, full hot-water and heating function test. 5. 05 ### Documentation OFTEC service record, written report, sticker on boiler, digital copy emailed. Insurance/warranty proof. Why customers choose Reactive ## No guesswork. No upsell. Just the work, done right. - ### OFTEC registered Our engineers hold the OFTEC technician ticket. Legal, insured and properly trained for oil — not a gas engineer 'having a go'. - ### Tank-to-boiler full system We service tank, supply line, fire valve, filter and burner — not just the boiler casing. - ### All major brands Worcester Greenstar, Grant Vortex, Firebird Envirogreen, Warmflow, HRM. Spares carried for common models. - ### Fixed-price installs Same one-number pricing as our gas work. Tank, line, boiler, commissioning — all in. - ### Annual reminder service Auto-reminder before service due date. We schedule before winter, not in the middle of it. - ### Free oil-grade CO alarm Every install gets a CO alarm rated for oil-fired appliances at the manufacturer-spec position. ![OFTEC engineer inspecting an oil boiler burner with nozzle and electrodes visible during annual service](/__l5e/assets-v1/c7600ad9-eceb-4966-ac76-3a6bf2af0927/img-002.jpeg) In detail ## Oil boiler servicing — what's actually done, and why nozzle replacement matters An oil burner sprays atomised kerosene through a precision nozzle into the combustion chamber, where it's ignited by a high-voltage spark across two electrodes. The nozzle is a wear part — its tiny orifice (typically 0.5 to 1.5 US gallons per hour spray rate) erodes over a year's use. A worn nozzle sprays unevenly, causing uneven combustion, smoke, soot deposits and gradual CO production. Industry standard practice — and OFTEC requirement — is to replace the nozzle at every annual service, regardless of how it looks visually. Spares cost a few pounds; the boiler runs cleaner all year on a fresh one. Engineers who skip the nozzle to save five minutes are not servicing properly. The other annual jobs: electrode gap reset (typically 3–4mm depending on burner), flexi-hose check, oil filter cartridge swap, photo-cell clean, fan blade clean. Then a smoke number test using the Bacharach scale (we look for sub-1 on a clean burner), and a CO/CO2 analysis to confirm clean combustion. - ### Worcester Greenstar Heatslave Common across Northants. Electrode and nozzle service-critical. We carry spares. - ### Grant Vortex Wall-hung and floor-standing variants. Reliable when serviced; brittle when ignored. - ### Firebird Envirogreen Popular in stone properties. Different burner head design — needs OFTEC-trained eyes. - ### Warmflow Agentis Good off-grid choice. Standard service intervals apply. - ### Tank inspection Plastic tank crack check, steel tank corrosion check, base / bunding integrity, fire valve test. - ### Tank replacement Old tank decommissioning + new bunded tank install + line + fire valve + commissioning. Honest pricing ## How much does oil boiler service, install or repair cost? Oil boiler work is priced similarly to gas, with small premiums on installs (oil-spec boilers and tanks add cost). Annual service includes the nozzle and filter swap as standard. Annual oil boiler service Fixed price Burner strip, nozzle + filter swap, electrode reset, smoke and combustion test, OFTEC service record. Oil boiler installation Fixed price Worcester / Grant / Firebird condensing boiler, full install, system flush, MagnaClean, registered warranty — quoted after free survey. Oil tank replacement Fixed price Decommission old tank, new bunded plastic or steel tank, supply line, fire valve, commissioning. ### What changes the price - Boiler make, model and kW output - Tank type (plastic bunded vs steel) and capacity - Distance from tank to boiler - Existing supply line and fire valve condition - Whether old tank requires environmental decommissioning - Annual service plan vs one-off Free, fixed-price quote — no obligation, no callout fee. [Get my fixed price](/contact) Areas covered ## Local cover across Northants & Rutland Oil heating is most common in our rural patch — Oundle, Oakham and the surrounding villages, Welland Valley properties, and the more isolated parts of west Northants. We service across all of it. - [Oil boiler servicing in Oundle ](/areas/oundle) - [Rutland oil boiler engineer ](/areas/oakham) - [Oil boiler repair Market Harborough ](/areas/market-harborough) - [OFTEC engineer Corby & rural NN17 ](/areas/corby) Who'll be doing the work ## The Reactive engineering team Our engineers hold OFTEC registration alongside Gas Safe and the LPG endorsement — the full off-grid trifecta. Most rural Northants homes end up needing one of those tickets at some point, and we cover all three under one phone number. - OFTEC Registered Technician (OFT10-105E, OFT10-101, OFT-T100) - Gas Safe Registered - Worcester Heatslave trained - Grant Vortex trained - Free oil-grade CO alarm with install FAQs ## Questions we actually get asked Anything not covered here? Pick up the phone — straight talk, no salesperson in the middle. [Call 07915 906262](tel:+447915906262) ### ### Do I need a different engineer for oil vs gas? ### ### How often should I service an oil boiler? ### ### Are modern oil boilers efficient? ### ### Can I replace my oil tank myself? ### ### What's diesel bug and how do I avoid it? ### ### Will you work on my Aga or oil cooker? ### ### Do you do tank-to-boiler line replacements? ### ### Is the work guaranteed? Related services [ In this category Fixed-price boiler installation ](/boiler-installation)[ In this category Same-day boiler repair ](/boiler-repair)[ In this category Annual boiler service ](/boiler-servicing)[ You may also need LPG engineer for off-grid homes ](/lpg-engineer)[ Back to hub All Heating & Gas Services ](/heating-gas-services) Ready when you are ## Reliable oil heating, properly serviced. Book a service. OFTEC registered, all major brands, free oil-grade CO alarm on every install — across rural Northants, Rutland and Leicestershire. [Enquire Now](/contact) [07915 906262](tel:+447915906262) Last updated May 2026 · Reactive Gas Heating and Plumbing Services Limited · 9 Rutherford Court, Corby NN17 4SJ · Gas Safe Registered · OFTEC Registered · Checkatrade Verified [![Reactive Gas Heating & Plumbing logo](/__l5e/assets-v1/51d713a4-18a4-4b5f-96fb-2fcce169e56c/reactive-logo.png)](/) Reactive Gas Heating and Plumbing Services Limited. Plumbing, heating and gas engineers based in Corby — covering Northamptonshire, Rutland, Leicestershire and the East Midlands. [07915 906262 ](tel:+447915906262) [0800 861 1593 (freephone)](tel:+448008611593) [07488 883576](tel:+447488883576) [07342 043953](tel:+447342043953) [info@reactiveph.co.uk](mailto:info@reactiveph.co.uk) 9 Rutherford Court Corby, Northamptonshire NN17 4SJ [](https://www.facebook.com/Reactiveservices/)[](https://www.instagram.com/reactivegasheatingplumbing/) ### [Plumbing](/plumbing-services) - [Emergency Plumbing](/emergency-plumbing) - [Drain Unblocking & Drainage](/drain-unblocking) - [Leak Detection & Repair](/leak-detection-repair) - [Power Flushing](/power-flushing) ### [Heating & Gas](/heating-gas-services) - [Boiler Installation](/boiler-installation) - [Boiler Repair & Breakdown](/boiler-repair) - [Boiler Servicing](/boiler-servicing) - [LPG Installation & Servicing](/lpg-engineer) - [Oil Boiler Installation & Servicing](/oil-boiler-engineer) ### [Areas Covered](/areas) - [Corby](/areas/corby) - [Kettering](/areas/kettering) - [Desborough](/areas/desborough) - [Rothwell](/areas/rothwell) - [Oundle](/areas/oundle) - [Market Harborough](/areas/market-harborough) - [Wellingborough](/areas/wellingborough) - [Oakham](/areas/oakham) - [Stamford](/areas/stamford) - [Peterborough](/areas/peterborough) ### Company - [About our team](/about) - [Customer Reviews](/reviews) - [Recent Work](/our-work) - [Maintenance Plans](/maintenance-plans) - [Current Offers](/specials) - [Contact](/contact) - [Privacy Policy](/privacy-policy) - [Terms & Conditions](/terms-conditions) ### Opening Hours - Monday: 08:00–18:00 - Tuesday: 08:00–18:00 - Wednesday: 08:00–18:00 - Thursday: 08:00–18:00 - Friday: 08:00–18:00 - Saturday: 08:00–13:00 - Sunday: Closed - 24/7 emergency cover — call any time outside working hours ### Guides & Blog - [Combi vs System vs Regular Boilers: Which Is Right for You?](/guides/combi-vs-system-vs-regular-boilers) - [How Much Does a New Boiler Cost in 2026?](/guides/how-much-does-a-new-boiler-cost) - [8 Signs You Need a New Boiler (Not Just a Repair)](/guides/signs-you-need-a-new-boiler) - [Common Boiler Fault Codes Explained](/guides/common-boiler-fault-codes-explained) - [What to Do in a Plumbing Emergency](/guides/what-to-do-in-a-plumbing-emergency) - [How to Turn Off Your Water at the Mains](/guides/how-to-turn-off-water-at-the-mains) © 2026 Reactive Gas Heating and Plumbing Services Limited. Registered in England & Wales, company no. 13663757. Gas Safe Registered · OFTEC Registered · Checkatrade Verified [Call Now](tel:+447915906262)[Fixed Boiler Quote](/boiler-quote)