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Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner
Vaillant

Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner

In StockEnergy A++

Available to order — dispatched on the lead time shown below.

£917.910

Trade pricing available — apply or sign in for your trade rate

2-4 working days
UK-Wide Delivery
Free UK mainland delivery on in-stock units
🇪🇺 EU Delivery available
Dispatched in 3–7 working days, then 5–10 working days EU transit
Orders under €150 ship VAT-paid at checkout (IOSS, no charges on delivery). Orders of €150 or more ship DDU — import VAT and customs duty are collected by the courier on delivery.

Retail prices include VAT.

The Vaillant climaVAIR pro VAI5-035WN 3.5kW (12,000 BTU) inverter split system offers premium German engineering tailored for medium-sized living rooms, open-plan dining spaces, and home office environments. Operating on eco-conscious R32 refrigerant, the system achieves an outstanding A++ seasonal energy rating for cooling alongside high-efficiency heat pump warming in winter. Key comfort features include a high-velocity turbo mode for rapid thermal adjustment, an intelligent 'I Feel' sensor incorporated into the remote handset, and four selectable fan speeds that maintain hushed acoustic levels. The active ionisation and multi-stage filtration system capture particulate airborne pollutants, ensuring fresh indoor environments for allergy sufferers. The integrated Wi-Fi interface links easily to your mobile device, granting complete operational oversight from anywhere. Professional F-Gas installation is legally required.

1

Need it installed?

We'll match you with a local HVAC engineer.

Smart-home ready

Connects natively with the systems below — control by app or voice.

Amazon AlexaGoogle HomeiOS / Android App
  • Free UK mainland delivery on in-stock units
  • Manufacturer warranty included
  • 14-day returns

Cooling Capacity

12,000 BTU

Energy Rating

A++

Recommended Room

25-35 m²

Technical documents & videos

More from Vaillant →

Official Vaillant manual

The manufacturer's PDF for this model is being sourced and will be downloadable here.

All Vaillant catalogues and rangesMissing a document? Ask our team and we will send it over.

Full Specifications

Cooling Capacity12,000 BTU
Recommended Room Size25-35 m²
Energy RatingA++
Smart HomeAmazon Alexa, Google Home, iOS / Android App
Noise Level—
CategorySplit System AC
SKUVAI5-035WNO-KIT

Physical dimensions

Exact dimensions for this model are being confirmed with Vaillant — ask us and we will send the cut sheet with mounting and clearance figures.

Description

The Vaillant climaVAIR pro VAI5-035WN 3.5kW (12,000 BTU) inverter split system offers premium German engineering tailored for medium-sized living rooms, open-plan dining spaces, and home office environments. Operating on eco-conscious R32 refrigerant, the system achieves an outstanding A++ seasonal energy rating for cooling alongside high-efficiency heat pump warming in winter. Key comfort features include a high-velocity turbo mode for rapid thermal adjustment, an intelligent 'I Feel' sensor incorporated into the remote handset, and four selectable fan speeds that maintain hushed acoustic levels. The active ionisation and multi-stage filtration system capture particulate airborne pollutants, ensuring fresh indoor environments for allergy sufferers. The integrated Wi-Fi interface links easily to your mobile device, granting complete operational oversight from anywhere. Professional F-Gas installation is legally required.

Compare similar units

Side-by-side specs for other split system ac in a similar BTU range.

This Unit
Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner

Vaillant

Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner

Samsung 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

Samsung

Samsung 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

Midea Comfee 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

Midea

Midea Comfee 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

TCL 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

TCL

TCL 12000 BTU Smart A++ Wall Mounted Split Air Conditioner with Heat Pump

Cooling Capacity
12,000 BTU
12,000 BTU
12,000 BTU
12,000 BTU
Room Size
25-35 m²
—
—
—
Energy Rating
A++
A++
A++
A++
Heating Capable
Yes (heat pump)
Yes (heat pump)
Yes (heat pump)
Yes (heat pump)
Smart Home
Amazon Alexa, Google Home, iOS / Android App
Yes
Yes
Yes
Stock
In Stock
In Stock
In Stock
In Stock
Price inc VAT
£917.91
£604.97
£417.97
£405.90

Common questions about the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner

How many BTU is the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner?

The Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner has a cooling capacity of 12,000 BTU, suitable for 25-35 m².

What room size is the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner suitable for?

The Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner is recommended for rooms 25-35 m².

Can I install the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner myself?

No — this unit requires professional installation by a qualified F-gas engineer. Use our Find an Installer service to get matched with a local HVAC professional.

Is the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner smart-home compatible?

Yes — the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner supports Amazon Alexa, Google Home, iOS / Android App for app and voice control.

How long does delivery of the Vaillant climaVAIR pro VAI5-035WN 3.5kW Inverter Split Air Conditioner take?

This unit is 2-4 working days. Delivery is then 1–2 working days to most UK mainland addresses, and 3–6 working days into the EU.

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Annual energy savings estimate

How much this A++-rated unit could save versus a standard C-rated model, based on your usage.

This unit

97 kWh/yr

EER 13

Standard model

158 kWh/yr

EER 8

Est. saving

£16.44

61 kWh/yr less

Estimate based on the unit's energy-rating efficiency factor and cooling capacity (12,000 BTU). Actual savings vary with room size, climate and usage patterns.

Winter heating cost: this AC vs electric heaters

This unit reverses to heat your room in winter. Based on its 4 kW heat output used 5 hrs/day over a 150-day UK heating season at £0.27/kWh.

Electric heater / season

£769

This AC / season

£256

You save / season

£513

~67% less electricity

Heating methodElectricity / seasonCost / seasonEfficiencySummer cooling
This heat-pump AC950 kWh£256Up to 300%
Plug-in electric heater2850 kWh£769100%
Electric storage heater2850 kWh£769100%

Heat output estimated from this unit's 12,965 BTU/hr rating. A heat pump moves heat (COP ≈ 3), so it uses about a third of the electricity of a direct-electric heater for the same warmth. Actual savings vary with room size, insulation, tariff and usage. See the full comparison →

Share your savings

This heat-pump AC costs only £256/season to heat a room vs £769 for an electric heater - that's £513 saved. https://stockool.store/products/vaillant-climavair-pro-vai5-035wn-3-5kw-inverter-split-air-conditioner

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