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Scarlet Heating & Plumbing

Heating & boilers

Boiler stopped?Let’s work out why.

We diagnose before we quote, carry the parts that actually fail, and tell you honestly when a boiler is worth fixing and when it is throwing money at a lost cause.
Diagnostic
£85, credited against the repair
First-visit fix
Most common faults
All makes
Worcester, Vaillant, Ideal, Baxi
Call 07490 623966Check your symptom first

Free fault guide

What is your boiler actually doing?

Pick the symptom and we will tell you the usual causes, what is safe to check yourself, and exactly where it stops being a DIY job. Sometimes it is flat thermostat batteries and you save yourself a call-out.

Pick the closest symptom

Choose a symptom to see what is likely going on

You will get the usual causes, the checks that are safe to make yourself, and an honest note on where it stops being a DIY job.

How we charge

Diagnose first. Price second. Then you decide.

The thing people hate about repair call-outs is not knowing what it will cost until it is already done. So we split it.
  1. 01

    £85 diagnostic

    We come out, find the fault properly and tell you what it is. That fee is fixed and it covers up to an hour on site.

  2. 02

    A price, before we touch it

    You get the parts cost and the labour to fix it, as one number, before any work starts. If you want to think about it, that is fine.

  3. 03

    The diagnostic comes off

    Go ahead with the repair and the £85 is credited against the final bill. Decline it and you have still paid for a proper diagnosis you can take anywhere.

What is on the van

Roughly eighty per cent of domestic boiler faults come down to a handful of components. We carry them, which is why most repairs finish on the first visit rather than turning into a two-day wait for a courier.

  • Pressure relief valves and filling loops
  • Expansion vessels and re-charge kits
  • Diverter valve cartridges and actuator heads
  • Pumps and pump heads
  • Thermistors, sensors and thermocouples
  • Ignition electrodes and leads
  • Auto air vents and system valves
  • Radiator valves and TRV heads
  • Fuses, PCB relays and wiring centres
  • Inhibitor, cleanser and leak sealer

The repair-or-replace conversation

Our rule of thumb: under eight years old with an available part, repair it. Over twelve, on its second repair this year, or the part is obsolete — replacing is usually the better spend. We will tell you which side of that line you are on, including when it means a smaller job for us.

Smell gas? This page is not your first stop.

Turn the gas off at the meter, open the windows, leave the switches alone and get outside. Then ring the National Gas Emergency Service — free, 24 hours a day. We will handle the repair afterwards.

0800 111 999

Straight answers

Repair questions

Including the one nobody likes asking: is it even worth fixing?
All questions
Should I repair my boiler or replace it?
As a rule of thumb, if the boiler is under eight years old and the part is available, repair it. If it is over twelve, has needed more than one repair recently, or the part is obsolete, the money is usually better spent on a replacement. We will tell you plainly which side of that line you are on, including when the answer means a smaller job for us.
Why does my boiler keep losing pressure?
Losing pressure means water is leaving the sealed system somewhere. The three usual causes are a leaking radiator valve or pipe joint, a failed expansion vessel, or a passing pressure relief valve discharging outside through the small copper pipe. Topping it up repeatedly hides the problem and introduces fresh oxygenated water, which accelerates corrosion — it is worth finding the actual cause.
My radiators are cold at the bottom — what does that mean?
Cold at the bottom and warm at the top usually means sludge, which is magnetite built up from internal corrosion. Cold at the top and warm at the bottom is trapped air and just needs bleeding. Sludge is treated with a power flush and prevented from returning by fitting a magnetic filter and dosing the system with inhibitor.
Do you charge for a quotation?
No. Quotes for installations, bathrooms and heating work are free, and we give you a written fixed price rather than a rough figure over the phone. Diagnostic visits for a fault are chargeable, because that is engineering time on site — but the call-out is credited against the repair if you go ahead with it.
How quickly can you come out?
Breakdowns in Llanelli, Burry Port and the surrounding villages can usually be seen the same or next working day, and Swansea and Carmarthen within a few days. Planned work such as a new boiler or a bathroom is booked to a date that suits you. If you have no heat or hot water, say so when you get in touch and we will prioritise it.

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No heat or hot water? Get it looked at.

Tell us the symptom and any fault code and we will get you into the diary. Urgent jobs are quicker by phone — 07490 623966.

Book a repair07490 623966
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