Vaillant 0020266328 vs 0020269259Two part numbers, one cooling resistor — and why that is
If you have searched for the Vaillant cooling resistor you will have seen it listed under two part numbers: 0020266328 and 0020269259. They are the same component. This page explains why two numbers exist, confirms they are interchangeable, and tells you which to order.
Updated
The short answer
Vaillant part numbers 0020266328 and 0020269259 refer to the same cooling coding resistor — the small "code plug" that authorises cooling mode on a compatible Vaillant aroTHERM or VWL heat pump. They are functionally and electrically identical and interchangeable.
Whichever number is printed on the bag you receive, the part does exactly the same job in exactly the same way. There is no "better" version and no version to avoid.
Why two numbers exist
It is common for a manufacturer to carry a single component under more than one part number over its lifetime. Numbers can change between production runs, when packaging or labelling is updated, or when a catalogue is re-organised and a part is re-referenced.
None of that changes the component itself. The resistor value — the thing the heat pump controller actually reads — is the same. The two numbers are best thought of as two labels for one part, much like a product sold under an old and a new code at the same time.
Which one should you order?
Either. Order whichever is in stock at the best price. If a supplier lists only one number, that is the correct part. If a supplier lists both, they are the same item.
The resistor sold through vheatc.site is supplied as the genuine Vaillant cooling coding plug and is correct whether your paperwork, installer or heat pump documentation refers to 0020266328 or 0020269259. If you want certainty for a specific heat pump, your installer can confirm the cooling coding plug against the model in the Vaillant installer manual.
A side-by-side summary of the two part numbers.
| Aspect | 0020266328 | 0020269259 |
|---|---|---|
| Part type | Cooling coding resistor (code plug) | Cooling coding resistor (code plug) |
| Function | Authorises cooling mode | Authorises cooling mode |
| Electrically | Identical resistor value | Identical resistor value |
| Interchangeable | Yes — with 0020269259 | Yes — with 0020266328 |
| Which to order | Either is correct | Either is correct |
Frequently asked questions
Are 0020266328 and 0020269259 really the same part?
Yes. They are the same Vaillant cooling coding resistor, functionally and electrically identical and fully interchangeable. The two numbers are simply two references for one component.
Which number will I receive?
You may receive a bag printed with either number depending on production run. Whichever it is, the part is correct and does the same job — there is no difference in fitting or function.
My installer asked for one specific number — will the other do?
Yes. The two numbers are interchangeable, so the part you receive will be correct regardless of which number your installer quoted. If you would like reassurance, your installer can confirm it against the Vaillant installer manual for your model.
Is the newer number a better or updated version?
No. Neither number is an upgrade of the other. The resistor and its value are the same; the number difference reflects production and cataloguing, not any change to the part.