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Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)
Mitsubishi Heavy Industries

Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)

In StockEnergy A+++
£1,171.10£1,195.00Save £23.90

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

Dispatched in 2-3 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 Mitsubishi Heavy Industries SRK35ZSX-WF / SRC35ZSX-W is a flagship Diamond Series split system engineered for discerning UK homeowners. Outputting 3.5kW (12,000 BTU) cooling and 4.3kW (14,600 BTU) heating, it delivers peak climate comfort for spaces up to 35m². Rated at a flawless A+++ for cooling and heating efficiency, it combines advanced inverter compressors with an intelligent human presence sensor that adjusts cooling or switches to standby when the room is empty. Integrated Wi-Fi connects directly to your smartphone through the Smart M-Air application, allowing remote programming and smart home integration with Amazon Alexa and Google Home. Dual-flap air vectoring ensures precision climate control, while high-efficiency allergen filtration traps fine particulate matter and destroys allergens. F-Gas certified installation mandatory.

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 Home
  • Free UK mainland delivery on in-stock units
  • Manufacturer warranty included
  • 14-day returns

Cooling Capacity

12,000 BTU

Energy Rating

A+++

Recommended Room

Up to 35m²

Technical documents & videos

More from Mitsubishi Heavy Industries →

Official Mitsubishi Heavy Industries manual

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

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

Full Specifications

Cooling Capacity12,000 BTU
Recommended Room SizeUp to 35m²
Energy RatingA+++
Smart HomeAmazon Alexa, Google Home
Noise Level—
CategorySplit System AC
SKUMHI-SRK35ZSX-WF-SET

Physical dimensions

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

Description

The Mitsubishi Heavy Industries SRK35ZSX-WF / SRC35ZSX-W is a flagship Diamond Series split system engineered for discerning UK homeowners. Outputting 3.5kW (12,000 BTU) cooling and 4.3kW (14,600 BTU) heating, it delivers peak climate comfort for spaces up to 35m². Rated at a flawless A+++ for cooling and heating efficiency, it combines advanced inverter compressors with an intelligent human presence sensor that adjusts cooling or switches to standby when the room is empty. Integrated Wi-Fi connects directly to your smartphone through the Smart M-Air application, allowing remote programming and smart home integration with Amazon Alexa and Google Home. Dual-flap air vectoring ensures precision climate control, while high-efficiency allergen filtration traps fine particulate matter and destroys allergens. F-Gas certified installation mandatory.

Compare similar units

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

This Unit
Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)

Mitsubishi Heavy Industries

Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)

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Cooling Capacity
12,000 BTU
12,000 BTU
12,000 BTU
12,000 BTU
Room Size
Up to 35m²
—
—
—
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
Yes
Yes
Yes
Stock
In Stock
In Stock
In Stock
In Stock
Price inc VAT
£1,171.10
£604.97
£417.97
£405.90

Common questions about the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)

How many BTU is the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W)?

The Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) has a cooling capacity of 12,000 BTU, suitable for Up to 35m².

What room size is the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) suitable for?

The Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) is recommended for rooms Up to 35m².

Can I install the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) 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 Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) smart-home compatible?

Yes — the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) supports Amazon Alexa, Google Home for app and voice control.

How long does delivery of the Mitsubishi Heavy Industries 3.5kW Diamond Flagship Split System (SRK35ZSX-WF / SRC35ZSX-W) take?

This unit is dispatched in 2-3 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

90 kWh/yr

EER 14

Standard model

158 kWh/yr

EER 8

Est. saving

£18.31

68 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

£867

This AC / season

£289

You save / season

£578

~67% less electricity

Heating methodElectricity / seasonCost / seasonEfficiencySummer cooling
This heat-pump AC1070 kWh£289Up to 300%
Plug-in electric heater3209 kWh£867100%
Electric storage heater3209 kWh£867100%

Heat output estimated from this unit's 14,600 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 £289/season to heat a room vs £867 for an electric heater - that's £578 saved. https://stockool.store/products/mitsubishi-heavy-industries-3-5kw-diamond-zsx-wf-split-system

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