Ordering the wrong boiler spare part is frustrating. You strip the boiler down, wait for delivery, and then realise the electrode or valve doesn’t fit. At Boiler Spares Ltd, we want you to get the right part first time — every time.
This guide shows you exactly how to find your boiler model number, locate the part number on your old component, and match it to the correct spare in our catalogue.
Step 1: Find Your Boiler Model Number
Every boiler has a data plate or label that shows the exact model and serial number. This is the most important piece of information when ordering spares.
Where to look:
Table
| Boiler Brand | Where the Data Plate Is |
| Baxi | Inside the drop-down front panel, on the right-hand side |
| Worcester Bosch | Inside the front panel, on the left or underneath |
| Vaillant | On the underside of the boiler, or inside the front cover |
| Ideal | Behind the front panel, usually on a silver sticker |
| Glow-worm | Inside the front casing, on the left |
| Alpha | On the underside or inside the front panel |
Tip: Take a clear photo of the entire data plate with your phone. You’ll need the GC number and the model name (e.g., “ecoTEC Plus 831”).
Step 2: Find the Part Number on the Old Component
If you have already removed the faulty part, the part number is usually stamped, printed, or on a sticker directly on the component.
Where to look on common parts:
Table
| Part Type | Where the Part Number Is |
| Ignition electrode | Stamped on the ceramic body or metal bracket |
| Diverter valve | On a sticker on the valve body or motor head |
| Pump | On the pump head or motor label (e.g., Grundfos UPM4) |
| Pressure sensor | On the plastic body or wiring plug |
| Thermistor | On the metal probe or blue/black plastic head |
| Expansion vessel | On a large sticker showing litres and bar rating |
Can’t read the number? Take a clear photo of the part from multiple angles and email it to us — we can identify it for you.
Step 3: Match the Part Number on Our Website
Once you have the part number or boiler model, use our search bar:
- Search by part number: Type the exact number (e.g., 248066 or BI1462100)
- Search by boiler model: Type the model name (e.g., Baxi Duo-tec 28)
- Browse by category: Use our category menu to find the part type
Our product pages show:
- The exact part number
- A list of compatible boiler models
- Photos of the genuine and compatible options
- Whether the part is in stock
Step 4: Check the “This Part Fits” Tab
On every product page at Boiler Spares Ltd, we list the exact boiler models that the part fits. Before you order, scroll down and check that your boiler model appears in the list.
If your model is not listed: Contact us before ordering. We may be able to source the correct alternative or confirm compatibility.
Common Mistakes When Ordering Boiler Parts
Table
| Mistake | Why It Happens | How to Avoid It |
| Ordering by boiler brand only | “Baxi pump” fits 50+ models | Always include the model name or GC number |
| Ignoring the GC number | The GC number is the unique identifier | Write it down from the data plate |
| Assuming all electrodes are the same | Electrodes vary by length and connector | Match the part number exactly |
| Buying a full valve when only the diaphragm is needed | Diaphragms fail more often than the valve body | Check if a repair kit is available first |
| Not checking if the part is genuine or compatible | Some customers need genuine for warranty | Read the product description carefully |
What If I Can’t Find the Part Number?
If the part number is worn off or you can’t access the boiler:
Option 1: Use our categories Browse by part type — ignition electrodes, pumps, diverter valves, etc. — and match the photo to your old part.
Option 2: Contact us Send us:
- A photo of the boiler data plate
- A photo of the old part
- A description of the fault (error code, symptoms)
We identify parts for customers every day and will reply quickly with the correct part number.
FAQ
What’s the difference between a GC number and a model number? The GC number (e.g., GC No. 41-473-97) is the official Gas Council number that uniquely identifies your boiler. The model name (e.g., “Greenstar 30i”) is the marketing name. Both work for finding parts, but the GC number is the most accurate.
Can I use a compatible part if my boiler is under warranty? No — using non-genuine parts usually voids the manufacturer’s warranty. Stick to genuine parts for warranty repairs.
Do I need to be Gas Safe to fit a spare part? You can fit electrical parts like electrodes, pumps, and sensors yourself if you isolate the power and water. Any work on the gas valve, burner, or gas pipe must be done by a Gas Safe registered engineer.
What if I order the wrong part? Contact us as soon as possible. If the part is unopened and in original condition, we can arrange an exchange or refund.
Find Your Part Now
Now you know how to identify the right boiler spare part, it’s time to order.
- Search by part number →
- Browse by boiler brand →
- Browse by part type →
- Contact us for help →
Boiler Spares Ltd — Huddersfield, UK. Fast delivery on genuine and compatible parts for all major brands.