Integrated Heat Pump R290 · GWP 3 149 Litres CoP 3.11 Energy Rating A+ Wi-Fi via hOn App 1,200W Backup Heater IPX4
The Haier HP150M8C is the compact model in Haier's M8 heat pump water heater range — a space-efficient, highly energy-efficient integrated air-source heat pump cylinder for 1–2 person UK households or properties with limited installation space. Using R290 (propane) refrigerant with a GWP of just 3, the M8 achieves an A+ energy rating with a CoP of 3.11 at standard conditions. Its slimmer form factor and 160mm duct connection make it well-suited to tight spaces, while Wi-Fi control via the hOn app and a 1,200W backup heating element ensure convenience and reliability. A child lock feature adds an extra layer of safety for family homes.
Recovery & Heat-Up Times
10h 29m
Full heat-up 10°C to 55°C @ 7°C ambient (HP only)
55°C
Default setpoint (35–75°C range with element)
75°C
Max temp — with backup heater active
⏱️ Recovery Note: From 10°C to 55°C at 7°C ambient air, the M8 150L takes approximately 10 hours 29 minutes on heat pump only. Although this is longer than the M7 200L (6.7 hrs) in absolute terms, in normal daily use the cylinder maintains temperature and only partial reheating occurs — the M8's smaller volume means far less energy is required to maintain the target temperature. The 1,200W backup element reduces recovery time significantly when activated alongside the heat pump.
Key Features
- Integrated R290 heat pump — compact floor-standing unit, no outdoor unit required, minimal installation footprint
- 149L actual tank volume — ideal for 1–2 person households or properties with limited space
- A+ energy rating — certified efficiency, significantly lower running costs than a direct electric cylinder
- CoP 3.11 at 7°C (EN16147) — over 3× energy output versus electricity consumed
- R290 (propane) refrigerant — GWP of 3, zero ODP; future-proof against F-Gas phase-down regulations
- Dual-power heating: heat pump (240W rated) + 1,200W electric backup element
- Default temperature 55°C — adjustable 35–75°C with element active; Legionella-compliant at default setting
- Wi-Fi control via hOn app — iOS/Android, remote scheduling, mode selection, and energy monitoring
- Child lock — prevents accidental temperature changes or mode switching on the unit itself
- Magnesium anode — sacrificial anode protection against internal tank corrosion
- IPX4 water resistance — suitable for installation in bathrooms and wet utility rooms
- Operating range −7°C to +45°C — full UK year-round operation without restriction
- 160mm duct connection — flexible room-air or external-air supply configurations
- Maximum duct length 5m — suitable for compact duct runs in typical UK properties
- 0.8 MPa (8 bar) rated tank pressure — compatible with high-pressure mains water
- Anti-legionella cycle, anti-freeze protection, and condensate management built in
R290 GWP=3 Compact 149L Child Lock hOn App Wi-Fi IPX4 Rated Magnesium Anode
M8 vs M7 — Which should I choose? The M8 150L is Haier's compact model — best for 1–2 person homes or tight installation spaces. It uses a smaller 1,200W backup element (vs 1,500W in the M7) and has a 160mm duct connection with 5m maximum duct length. The M7 200L and 250L are better suited to larger households with higher daily hot water demand and have higher base CoP values (3.24 / 3.21 vs 3.11 for the M8).
Technical Specifications
What's Included
HP150M8C cylinder with integrated R290 heat pump
1,200W electric backup heating element
Magnesium anode (factory-installed)
UK user manual and installation guide
⚠️ G3 Compliance Required: The Haier M8, like all unvented hot water cylinders, must be installed by a G3-qualified person in compliance with Building Regulations Part G3. Suitable unvented safety controls (PRV, check valve, expansion vessel, T&P relief valve) must be fitted. Electrical connection must comply with BS 7671 and Part P.
ℹ️ hOn App: Available free for iOS and Android. Connects to the cylinder via 2.4GHz home Wi-Fi. Features include remote mode selection (Smart, Boost, Eco, Holiday), timer programming for off-peak tariff scheduling, energy consumption monitoring, fault alert notifications, and child lock toggle. The hOn app also provides access to Haier's broader smart home appliance ecosystem.
ℹ️ Duct Length Limitation: The M8 150L has a maximum duct run of 5 metres — shorter than the M7 range. This limits external air ducting to compact installations. For longer duct runs or larger room volumes, consider the M7 200L or M7 250L, which have greater flexibility. The 160mm duct connection is compatible with standard MVHR duct fittings.
Frequently Asked Questions
How long does the M8 150L take to heat from cold?
From 10°C to 55°C at 7°C ambient air, the HP150M8C takes approximately 10 hours and 29 minutes on heat pump only. Although this full cold-start time is longer than the smaller-volume M7 200L (6.7 hrs), the M8's 149L tank requires far less energy to maintain temperature in normal daily use. Activating the 1,200W backup element alongside the heat pump significantly reduces recharge time.
Why is the M8 150L recovery time longer than the M7 200L, despite being smaller?
The M8 uses a lower-rated heat pump compressor (240W rated vs 320W in the M7) and a smaller backup element (1,200W vs 1,500W). The M8 is optimised for compact, low-demand applications rather than rapid recovery. In practice, for 1–2 person households the tank rarely needs a full cold-start recovery — it maintains temperature efficiently between uses.
What is the child lock feature?
The child lock disables the physical controls on the unit itself, preventing accidental changes to temperature settings or operating mode. It can be toggled on or off via the hOn app, and does not affect remote control functionality through the app.
Does the M8 work for Legionella prevention?
Yes. The default setpoint is 55°C — above the 55°C storage temperature recommended for Legionella control. With the backup element active, the cylinder can reach 75°C for full anti-legionella pasteurisation. An automatic anti-legionella cycle is built into the control system and can be scheduled via the hOn app.
What are the duct requirements for the M8?
The M8 uses a 160mm duct connection with a maximum run of 5 metres. Both intake and exhaust connections are required. The unit can also draw room air directly without ducting if the installation room has adequate volume. Duct insulation is recommended to prevent condensation on the duct exterior, particularly in cold locations.
Is the M8 suitable for a small flat or apartment?
Yes — the M8 150L is Haier's most space-efficient integrated HPWH model and is well suited to smaller properties. Its compact footprint, 149L capacity, and 5m duct limitation make it ideal for flats, small terraced houses, and 1–2 person households. The child lock is also useful in shared or family living situations.
