Vaillant
Vaillant Automatic Air Vent 20278074
Automatic air vent, part number 20278074, for Vaillant Arotherm PLUS /6 heat pump units.
At a glance
- Also known as 1391482
£20.18
£16.82 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Vaillant 20278074 is an automatic air vent used on Vaillant Arotherm PLUS /6 air-to-water heat pump units. It continuously releases trapped air from the water circuit, helping to keep flow rates stable and preventing air locks within the system. It is a serviceable component intended for fitment to the appliance models listed below.
Signs this part needs replacing
- Water weeping or dripping from the vent body
- Persistent gurgling or air noise in the heat pump circuit after repeated venting
- System pressure that will not hold or falls steadily without an obvious leak elsewhere
- Air accumulating at high points in the circuit despite the vent being fitted
- Corrosion or scale build-up around the vent head
Before you order
- Confirm the appliance model and variant against the fit list above
- Check the part number on the existing vent matches 20278074
- Verify whether the unit is an early or R1/R2 build, as fitment varies by variant
- Isolate and depressurise the circuit before removal
Compliance
| Alternative numbers | 1391482 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT aroTHERM PLUS /6 VWL 105/6 A 230V S2 (2020-2021) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 125/6 A 230V S2 (2020-2021) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 35/6 A 230V S2 (2020-2022) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 35/6 A 230V S2 R1 (2022) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 35/6 A 230V S2 R2 (2023) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 55/6 A 230V S2 (2020-2022) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 55/6 A 230V S2 R1 (2022) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 55/6 A 230V S2 R2 (2023) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 65/6 A 230V S2 R2 (2023) | — | — | — | |
| VAILLANT aroTHERM PLUS /6 VWL 75/6 A 230V S2 (2020-2023) | — | — | — |
Showing 10 of 11 compatible appliances.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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