How to check if your Vaillant heat pump can cool

Check 1 — The model code

Start with the data plate on the unit. Vaillant heat pump model codes begin with VWL for air-source units (the aroTHERM family) and VWF for some ground-source units. The full code, including any suffix, tells you exactly which unit you have.

The cooling plug is listed for the aroTHERM Plus range: VWL 35/6, VWL 55/6, VWL 75/6, VWL 105/6 and VWL 125/6. If your code is one of those, you are in the right family; for anything else, confirm with your installer manual or a Vaillant-approved installer.

Check 2 — The installer manual

Your installer manual is the most reliable document you hold. Look for the cooling section and the accessories or coding-plug section. If cooling is listed as an available function or accessory for your model, that is a strong indication the unit can be set up to cool.

If you no longer have the manual, you can usually download it from Vaillant’s website using the exact model code from the data plate.

Check 3 — Is a cooling plug already fitted?

Some systems already have the cooling plug fitted but cooling was never enabled — and some do not have it at all. Checking means inspecting the heat pump wiring at the coding-plug position, which is a job for a competent installer.

If the plug is already fitted, you may only need an installer to enable cooling in the menu. If it is not, you will need the plug — Vaillant 0020269259, or the identical 0020266328 — before cooling can be activated.

Check 4 — Ask a Vaillant-approved installer

The most dependable check is to ask a Vaillant-approved installer. They can confirm the cooling option for your exact model and serial number, check whether the plug is fitted, and tell you whether your emitters — radiators, fan coils or underfloor — are suitable for cooling.

An installer can also flag the bigger question: even a cooling-capable heat pump only cools usefully through emitters designed for it. That is worth knowing before you commit.

Frequently asked questions