Mitsubishi Electric MXZ Multi-split

The MXZ-F is the outdoor unit at the heart of a Mitsubishi Electric multi-split system: one condenser driving anywhere from two to six indoor units, so a whole cluster of rooms gets cooling and heating from a single box on the wall. That six-room ceiling is the widest coverage of the mainstream multi-splits, and the rest of the package is what the brand is known for: solid build, dependable long-term running and quiet operation indoors and out. On the popular 5.4 kW three-room model it holds an A+++ cooling and A++ heating label on R32 refrigerant, with SEER of 8.52 and SCOP of 4.61, and the indoor side is genuinely mix and match: plain MSZ-AY and MSZ-AP wall units where nobody is looking, the designer MSZ-LN (down to 19 dB(A)) or MSZ-EF Zen where they are, plus compact cassettes, concealed ducted units and floor consoles.

The trade-offs are the ones every multi-split carries. Every connected room runs in the same mode, so you cannot heat a bedroom while cooling an office; the outdoor unit is a single point of failure for the whole house; and the system is sized as one job, so adding a room later is constrained by the condenser you chose. Two quirks are specific to this family: the entry 3.3 kW MXZ-2F33 carries the weakest energy labels in the range, so the cheapest quote is also the least efficient, and the headline 5-year warranty only applies through an accredited installer with servicing conditions, otherwise it is 12 months, or 3 years if you register promptly. From two or three rooms up, and especially at four rooms and beyond where its rivals thin out, it is a sound premium choice that goes toe to toe with the Daikin 3MXM.

The MXZ-F is not a room unit you can see indoors. It is the outdoor condenser at the centre of a Mitsubishi Electric multi-split system: one box feeding refrigerant to between two and six indoor units, sized from 3.3 kW at the bottom of the family to 12 kW at the top. You choose it alongside the indoor units you want, and an F-Gas certified engineer commissions the whole thing as one sealed system, so this is a fitted product priced per home, not something you order with a delivery slot.

It suits a home that needs several rooms doing rather than one: a living room and two bedrooms on the mid-range three-port models, or most of a house on the five and six-port units at the top. The case over separate single splits is space and tidiness. One condenser instead of a row of them matters on a flat, a terrace or any frontage you care about, and it helps with planning too: a reverse-cycle outdoor unit can be permitted development in England within limits under the rules updated on 29 May 2025, and one unit is an easier fit within those limits than three. Check your local planning authority, and note the rules differ in Scotland, Wales and Northern Ireland. The catch is that all those rooms then depend on one unit, so it is a genuine trade-off rather than a free win.

The freedom is on the indoor side. The same outdoor unit accepts plain MSZ-AP and MSZ-AY wall units, the designer MSZ-LN and MSZ-EF Zen, compact ceiling cassettes, concealed ducted units and floor consoles, mixed however the sizing allows, with app control through MELCloud built into the current wall units. One thing to watch when comparing quotes: Mitsubishi Electric also sells a cheaper MXZ-HA multi family built around the budget MSZ-HR wall units. If one Mitsubishi quote comes in far below another, check which outdoor unit it is based on before assuming it is the same system.

The obvious rival is the Daikin 3MXM multi-split, and on paper the two are a dead heat. The 5.4 kW MXZ-3F54 posts SEER 8.52 and SCOP 4.61 against the 5.2 kW 3MXM52 at 8.50 and 4.60, both wear A+++ cooling and A++ heating labels on R32, and outdoor sound pressure is 46 dB(A) against around 47. Nobody should choose between them on those numbers.

The real differences are shape and style. The MXZ family goes to six rooms where the Daikin MXM range stops at five, which settles it for a larger house on one condenser. Daikin answers with a wider designer indoor choice, since the Stylish and Emura give more looks to pick from, while Mitsubishi counters with the MSZ-LN, quieter at minimum (19 dB(A)) and available in four finishes. Beyond that it usually comes down to which brand your installer knows best and prices keenest, and that is a sensible way to decide: both are premium, reliable systems, and we rate them level at 4.3. Get quotes for both and let the numbers for your own house pick the winner.

A multi-split is priced supplied and fitted, and the total scales with the number and type of indoor units, so there is no single shelf price. The MXZ-F outdoor unit alone runs from about £835 for the entry two-room 3.3 kW model to £3,666 for the six-room unit including VAT, but that is only one part: indoor units, pipework and fitting typically double to treble the total. As a working guide, a complete two-room Mitsubishi Electric multi-split fitted tends to run from roughly £3,000 to £4,500, a three-room system from about £4,500 to £7,000, and four to five rooms from £6,500 to £10,000 or more, with the spread driven by indoor unit choice (the designer LN and EF cost more than the plain AY) and by pipe runs, access and electrics. Budget for the electrical work too: the outdoor unit is hardwired to the consumer unit rather than plugged in, which is notifiable work and typically adds £400 to £700. Prices correct as of August 2026; always work from a fixed written quote for your own home.

Running costs are kept low by the inverter, which modulates one compressor to the actual load rather than running flat out. The 5.4 kW three-room model draws a nominal 1.32 kW in cooling, which is about 35p an hour with all three rooms working hard at the July 2026 Ofgem price cap unit rate of 26.11p per kWh, and considerably less once the rooms are at temperature. In heating, the SCOP of 4.61 means around four and a half units of heat for every unit of electricity, far cheaper than a plug-in heater delivering the same warmth. As a reverse-cycle air-to-air heat pump the system may qualify for the £2,500 Boiler Upgrade Scheme grant in England and Wales, but only if it replaces a fossil-fuel heating system and is fitted by an MCS-certified installer; comfort cooling added alongside a gas boiler does not qualify, and it is separate from the larger £7,500 air-to-water grant. Rates correct as of August 2026; the energy price cap changes quarterly, so check current rates before budgeting.