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Scarlet Heating & Plumbing

Off the gas grid

Oil boilers, tanks and the paperwork that goes with them

A large share of properties around Carmarthen, Llandeilo and the Towy Valley have no gas main at all. We service, repair, commission and replace oil-fired systems to OFTEC standards — including the tank, which is the bit most engineers walk straight past.
Full service
From £110
Time on site
1–2 hours
Covering
Rural Carmarthenshire
Book an oil serviceCheck my tank
Bunded oil storage tank on a concrete base at a rural Carmarthenshire property

Free self-assessment

Would your oil tank pass an inspection?

Seven questions you can answer standing next to it. Most people find out their tank is non-compliant when they try to sell the house or renew their insurance — which is the worst possible moment.

  • Is the tank bunded (a tank within a tank)?

  • Does it sit on a solid, level, non-combustible base?

  • Is it at least 1.8m from any door, window or non-fire-rated wall?

  • Is the tank free of cracks, bulges, rust and staining?

  • Is there a fire valve and a filter on the supply line?

  • Does the contents gauge actually work?

  • Has the boiler been serviced in the last 12 months?

0 of 7 answered — finish the list for a verdict.

What a full oil service involves

Six stages, and the tank is one of them

An oil service is more hands-on than a gas one. Parts get replaced rather than just inspected, and the fuel storage is part of the job.
  1. 01

    Nozzle and filter renewed

    Both are consumables. A worn nozzle sprays a poor pattern, which means incomplete combustion, sooting and wasted oil.

  2. 02

    Combustion chamber cleaned

    Baffles out, chamber and heat exchanger surfaces cleaned down. Soot is an insulator — a millimetre of it measurably drops efficiency.

  3. 03

    Photocell and electrodes

    Photocell cleaned so it can actually see the flame, electrodes checked and gapped to the manufacturer's figure.

  4. 04

    Fire valve and supply line

    The remote-sensing fire valve is tested, the line checked for leaks and air, and the filter bowl drained of any water.

  5. 05

    Tank, base and siting checked

    Condition, bunding, fire separation and the state of the base. This is the part that surprises people when they come to sell.

  6. 06

    Combustion set and recorded

    Burner set against an analyser and the readings written down, with full commissioning paperwork for your records and your insurer.

If the boiler is on its way out

Your realistic options, honestly compared

Off the gas grid, the choice is narrower than the internet suggests — and the right answer depends on your property, not on what is fashionable.

  • A modern condensing oil boiler

    For
    Cheapest to install, uses the existing tank and pipework, works with the radiators you already have and gives you high flow temperatures a stone cottage genuinely needs.
    Against
    You stay exposed to oil prices, and it is still a fossil fuel with a finite policy horizon.

    Usually the pragmatic choice for an older, poorly insulated property.

  • LPG

    For
    Cleaner burn, smaller tank footprint, and boilers are cheaper than oil models.
    Against
    Running cost per kWh is typically higher than oil, and you are tied to a supplier contract.

    Worth considering if the oil tank needs replacing anyway.

  • Air source heat pump

    For
    Lowest running cost per unit of heat if the property is well insulated, plus grant funding is often available.
    Against
    Needs low flow temperatures to work economically, which usually means larger radiators and serious insulation work first. Retrofitting into a solid-walled cottage is a project, not a swap.

    Excellent in the right house. Expensive disappointment in the wrong one.

How we schedule rural work

Driving forty minutes each way for one service makes the job expensive for everyone. So we group the outlying areas — Llandeilo and the Towy Valley, Kidwelly and Ferryside, the far side of Carmarthen — into planned runs and keep the travel off your invoice. Tell us your postcode when you book and we will tell you which run you are on and roughly when it next comes round. If it is urgent, that changes and we come out.

Straight answers

Oil heating questions

Written for properties off the gas grid, where the answers are genuinely different.
All questions
How often should an oil boiler be serviced?
Once a year, and oil boilers need it more than gas ones rather than less. The nozzle and fuel filter are consumables that wear in normal use, and as they do the combustion drifts out of tolerance — so the boiler burns more oil to produce the same heat. An annual service replaces both, cleans the combustion chamber and photocell, and resets the burner against an analyser reading.
What does an oil boiler service include?
We replace the nozzle and the fuel filter, clean the combustion chamber, baffles and photocell, check and set the electrodes, test the fire valve, inspect the tank, base and supply line, then run a full combustion analysis and set the burner to the manufacturer's figures. You get the readings in writing along with commissioning paperwork.
Why does my oil boiler keep locking out?
The most common causes are a blocked nozzle or filter, water or sludge drawn from the bottom of the tank, a failed photocell that cannot see the flame, or air in the supply line. Repeated resetting will not fix any of them and risks flooding the combustion chamber with unburnt oil. If it locks out twice, leave it and ring us.
Do I need a bunded oil tank?
In most domestic situations in Wales, yes. A bunded tank — a tank within a tank — is required where the capacity is over 2,500 litres, or where a spill could reach a watercourse, a borehole, a drain or a soakaway, which covers a great many rural properties around Carmarthen. A single-skin tank that splits is an environmental incident and the clean-up cost falls on the owner.
Can you convert my oil boiler to gas?
Only if there is a gas main in the road. Plenty of the properties we work on around Llandeilo, Kidwelly and rural Carmarthenshire have no gas supply at all, in which case the realistic choices are a modern condensing oil boiler, LPG, or a heat pump. We will give you an honest comparison rather than pushing whichever suits us.
Do you cover rural Carmarthenshire?
Yes. We group oil work in the outlying areas into planned runs — Llandeilo, the Towy Valley, Kidwelly and Ferryside — which keeps travel time off your bill. Tell us your postcode and we will tell you which run you fall on.

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Book your oil service or tank check

Nozzle, filter, combustion set and the tank properly inspected. Ring 07490 623966 or book online.

Book an oil service07490 623966
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