Mitsubishi 11.2 R32 1Ph Monobloc ASHP Outdoor Unit Std - PUZ-WM112VAA

Description

The Mitsubishi Ecodan PUZ-WM112VAA is an 11.2kW R32 monobloc air source heat pump outdoor unit for whole-house space heating and domestic hot water. This is the standard specification, built for typical UK inland installations and offering the same core performance as the coastal (-BS) version without the additional anti-corrosion coating.

As a monobloc unit, the entire refrigerant circuit is factory-sealed inside the outdoor casing — there is no refrigerant pipework to install and no F-Gas handling required on site. The heat pump connects to the building's heating system through water pipework alone, simplifying installation compared with a split, refrigerant-piped system.

Rated A+++ for ErP efficiency at 35°C flow and capable of delivering water up to 75°C, this unit suits both new-build underfloor heating systems and retrofit projects replacing a gas or oil boiler onto an existing radiator circuit. It maintains full rated output down to -25°C ambient temperature, giving dependable performance through UK winters.

11.2kW

Nominal Heating Output

A+++

ErP Rating (35°C)

SCOP 4.78

Seasonal Efficiency

45 dB(A)

Sound Pressure @ 1m

75°C

Max Flow Temperature

R32

Low-GWP Refrigerant

Please Note

This is the standard specification PUZ-WM112VAA. If the installation site is within roughly 3km of the coast, or exposed to salt spray, de-icing salt, or industrial airborne contaminants, specify the PUZ-WM112VAA-BS coastal protection variant instead — the standard casing does not carry the enhanced anti-corrosion coating and using it in a high-salinity environment can affect the manufacturer warranty.

11.2kW Monobloc Heat Pump

Self-contained R32 monobloc outdoor unit — all refrigerant is factory-sealed, so only water and electrical connections are needed on site, with no F-Gas certified engineer required for the refrigerant circuit.

A+++ Efficiency, SCOP 4.78

Rated A+++ at 35°C flow (SCOP 4.78) and A++ at 55°C flow (SCOP 3.34), delivering low running costs across both underfloor heating and radiator-based systems.

Full Output Down to -25°C

Maintains rated heating capacity in ambient temperatures down to -25°C, so performance is not compromised during UK winter cold spells.

Ultra-Quiet Operation

Sound pressure of just 45 dB(A) at 1 metre, making it suitable for close-boundary installations and noise-sensitive sites.

MELCloud Remote Control

MELCloud app connectivity (with optional Wi-Fi adaptor) gives remote scheduling, monitoring and diagnostics from a smartphone.

Up to 75°C Water Temperature

Can deliver flow temperatures up to 75°C, supporting direct boiler replacement onto existing radiator systems without needing to upsize emitters.

Compact Footprint

At 1050 x 480 x 1020mm and 119kg, the unit suits typical UK side-return and garden mounting positions.

MCS Certified

MCS certified for compliance with UK installation standards and eligibility for government renewable heating incentive schemes.

Model & Refrigerant

Model Code

PUZ-WM112VAA

Type

Ecodan R32 monobloc air source heat pump, standard specification

Refrigerant

R32 (GWP 675)

Refrigerant Charge

3.00 kg (2.03 t CO₂ equivalent)

Heating Performance

Nominal Heating Capacity (A7/W35)

11.2 kW, COP 3.73

Heating Capacity (A-7/W35)

11.2 kW output at low ambient

ErP Rating — 35°C Flow

A+++, SCOP 4.78 (ƞs 191%)

ErP Rating — 55°C Flow

A++, SCOP 3.34 (ƞs 134%)

Combination Heater Rating (Large Profile)

A+, ƞwh 148%

Maximum Flow Temperature

Up to 75°C

Operating Range & Sound

Operating Ambient Temperature

-25°C to +35°C DB

Sound Pressure Level @ 1m

45 dB(A)

Sound Power Level

60 dB(A)

Water Circuit

Water Pipe Connections

1" BSP (G1)

Water Flow Rate (A7/W35)

24.0 L/min

Water Pressure Drop

28 kPa

Electrical

Electrical Supply

220–240V, 50Hz, single phase

Nominal Running Current [Max]

10.9 A [28 A]

Fuse / MCB Rating

32 A

Dimensions & Weight

Width

1050 mm

Depth

480 mm

Height

1020 mm

Weight

119 kg

Important Safety Information

This is an outdoor unit only. To complete a working heating system you also need a compatible Ecodan hot water cylinder (which houses the plate heat exchanger, circulating pump and safety valves that link the outdoor unit to your wet heating circuit and hot water supply), plus a wired or wireless Ecodan controller for day-to-day operation. Installation and commissioning must be carried out by an MCS-certified installer in accordance with Mitsubishi Electric's design guidance and current Building Regulations.

What's Included

The PUZ-WM112VAA outdoor unit complete with factory-charged R32 refrigerant circuit, standard weatherproof casing, mounting feet, and manufacturer installation and commissioning documentation. No hot water cylinder or indoor controller is included.

What You Need for a Complete Installation

A compatible Ecodan hot water cylinder to store domestic hot water and house the system pumps and safety valves, a wired or wireless Ecodan controller, water pipework and insulation between the outdoor unit and cylinder, a weatherproof isolator and dedicated electrical supply, a suitable outdoor mounting base or anti-vibration feet, and system components such as an expansion vessel, filter, and buffer volume as specified by the installer's heat loss and system design calculations.

Is this unit suitable for a coastal property?

This standard PUZ-WM112VAA does not include the enhanced anti-corrosion coating. For sites within roughly 3km of the coast or exposed to salt-laden air, choose the PUZ-WM112VAA-BS coastal protection variant instead to protect the manufacturer warranty.

Does this unit include the hot water cylinder or indoor controls?

No. The PUZ-WM112VAA is the outdoor unit only. A separate Ecodan hot water cylinder and a wired or wireless controller are required to connect the heat pump to your wet heating system and hot water supply.

What refrigerant handling is required on installation?

None on site. This is a monobloc unit — the R32 refrigerant circuit is fully sealed and factory-charged, so installation only involves water pipework, electrical connection, and mounting.

How cold can it get before the heat pump loses performance?

The unit maintains its rated heating capacity down to -25°C ambient temperature, so it is designed to perform reliably through UK winters without a loss of output.

Can this heat pump provide domestic hot water as well as space heating?

Yes, when paired with a compatible Ecodan hot water cylinder, the unit can deliver flow temperatures up to 75°C, sufficient for both space heating and domestic hot water production.

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Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

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