Mitsubishi 11.2kW R32 3Ph Mono ASHP Outdoor Unit UQ Coastal - PUZ-WM112YAA-BS

Description

The Mitsubishi Ecodan PUZ-WM112YAA-BS is the three-phase, coastal-protection version of Mitsubishi's 11.2 kW R32 Ultra Quiet monobloc air source heat pump. Built for properties with a three-phase electrical supply or higher heat-loss requirements, it maintains reliable heating down to -25°C ambient and adds enhanced corrosion resistance for coastal installations. This listing is the outdoor unit only; pair it with a Mitsubishi FTC7 pre-plumbed cylinder or hydrobox for a complete system.

11.2 kW

Heating output

R32

Refrigerant

SCOP 4.78

35°C seasonal efficiency

3-Phase

380-415V supply

-25°C

Guaranteed operation

45 dB(A)

Sound pressure at 1m

BUS grant eligible

Eligible for the UK Boiler Upgrade Scheme grant when installed by an MCS-certified installer in an eligible property. The grant is paid directly to your installer and discounted from your quote.

-BS coastal protection

The -BS suffix denotes Mitsubishi's coastal-protection specification: enhanced corrosion-resistant casing treatment designed for installations exposed to salt-laden air near the sea. Functionally identical to the standard unit in output, efficiency and control compatibility — choose -BS specifically for coastal or otherwise corrosive environments.

MCS-certified installer required

To claim the BUS grant and validate full Mitsubishi manufacturer warranty, this heat pump must be installed and commissioned by an MCS-certified heat pump installer.

Property fit

The 11.2 kW Ecodan typically suits: large detached homes, older properties with retrofitted insulation, or three-phase-supply properties. Sizing should always follow a calculated heat loss assessment — Quality Heating offers free heat loss calculations.

Key features

R32 refrigerant

Lower GWP than legacy R410A units, with a sealed factory-charged circuit — no on-site F-Gas brazing required at install.

True monobloc

All refrigerant work happens inside the outdoor unit at the factory. The installer only connects water pipes indoors, reducing install time and risk.

Coastal corrosion protection

The -BS casing treatment is specifically designed to resist salt-air corrosion — extending outdoor unit lifespan in coastal and other harsh environments.

MELCloud enabled

Built-in MELCloud connectivity for remote control, monitoring, maintenance and technical support — no separate Wi-Fi module required to get started.

Ultra-quiet operation

Engineered for low sound levels suited to boundary-sensitive sites — see the sound pressure and power figures in the specification table for this exact model.

UK manufacturer warranty

Backed by Mitsubishi's UK warranty when commissioned by a Mitsubishi-approved engineer. Warranty registration documentation is supplied in the box.

Technical specification

Model code	PUZ-WM112YAA-BS
Quality Heating SKU	MITS-497793
Rated heating output	11.2 kW
Refrigerant	R32 (GWP 675)
Refrigerant charge	3.0 kg
Heating capacity (A7/W35)	13.50 kW, COP 4.55
Heating capacity (A2/W35)	12.50 kW, COP 3.17
Heating capacity (A-7/W35)	12.10 kW, COP 2.80
Heating capacity (A2/W55)	11.30 kW, COP 1.93
Cooling capacity (A35/W7)	10 kW
ErP rating — 35°C flow	A+++, SCOP 4.78
ErP rating — 55°C flow	A++, SCOP 3.43
Guaranteed operating range	-25°C to +35°C ambient
Electrical supply	380-415V, 50Hz, three phase
Maximum current	13 A
Fuse rating	16 A
Sound pressure level at 1m	45 dB(A)
Sound power level	60 dB(A)
Water flow rate	17.9 – 40.1 L/min
Water pressure drop	32 kPa
Water pipe connections	35 mm
Dimensions (W × D × H)	1050 × 480 × 1020 mm
Weight	119 kg
Coastal protection	Yes (-BS specification)
Compatible control platform	Mitsubishi FTC7
Smart connectivity	MELCloud enabled (built in)
Cascade capability	Up to 6 units for larger applications
BUS grant eligibility	Yes, when MCS-installed

What's in the box

• Mitsubishi Ecodan R32 outdoor monobloc unit (PUZ-WM112YAA-BS)
• Manufacturer installation and commissioning documentation
• Mitsubishi UK warranty registration card

What you'll also need (sold separately)

• FTC7 indoor controller (PAC-IF082B-E) or a pre-plumbed FTC7 cylinder
• Outdoor unit wall bracket or floor stand
• Anti-freeze valves on primary flow and return
• Magnetic system filter on the primary return
• Insulated flexible primary hoses and isolation valves
• Three-phase electrical isolator and consumer unit feed

Frequently Asked Questions

What does the -BS suffix mean?

-BS denotes Mitsubishi's coastal protection specification — an enhanced corrosion-resistant casing treatment for the outdoor unit. Output, efficiency and control compatibility are identical to the standard PUZ-WM112YAA; only the casing durability differs.

Why choose the 3-phase (YAA) version over the 1-phase (VAA) version?

Choose 3-phase where your property already has a three-phase electrical supply, or where your DNO recommends three-phase for a heat pump of this capacity. Output and efficiency are the same across both — the difference is purely electrical supply requirements.

Do I need to be MCS-registered to install this heat pump?

The Ecodan can technically be installed by any competent heating engineer, but to claim the UK Boiler Upgrade Scheme grant the install must be carried out by an MCS-certified installer.

Does this include the indoor cylinder?

No — this listing is for the outdoor unit only. You'll need either a Mitsubishi FTC7 pre-plumbed cylinder, or a third-party cylinder with the FTC7 Master Controller.

Can I cascade multiple units for a larger project?

Yes — up to 6 units of the same output can be cascaded to supply larger commercial or multi-dwelling projects.

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