The Stiebel Eltron HPA-O W Plus range is the fixed-white-finish counterpart to the standard HPA-O Plus monobloc air source heat pump — same natural R290 refrigerant, same inverter platform and exceptionally quiet operation, but supplied in a signal white (RAL 9003) casing as standard rather than the anthracite/white colour choice on the regular Plus range. It spans four capacities from 7.09 kW to 13.15 kW at A-7/W35, across both single-phase (HC 230) and three-phase (HC 400) electrical supplies. Use the variant table below to compare sizes and select the right unit for the property.
7.09–13.15 kW
Output Range (A-7/W35)
HC 230 / HC 400
Electrical Options
Pricing on request
Every HPA-O W Plus unit on this page is supplied at price on request. Stiebel Eltron systems are matched to the property — cylinder, hydraulic kit and controls are specified alongside the heat pump — so we confirm the full specification and cost with you directly before quoting. Please use the request a quote link on this page or contact our technical team with the property details below.
R290 refrigerant – installation clearances apply
These units use the natural refrigerant R290 (propane), which is mildly flammable (A3 classification). Installation must follow Stiebel Eltron's clearance and ventilation requirements for the refrigerant charge size, and electrical connection must be carried out by a competent electrician to Part P and BS 7671. Grid-connected units require a DNO notification (G98/G99) prior to commissioning.
Key features
Natural R290 refrigerant
Uses the natural refrigerant R290 (propane), GWP of just 3, future-proofed against F-Gas phase-down schedules affecting HFC refrigerants.
Inverter-matched heating output
A variable-speed inverter compressor matches heating output to demand rather than cycling on/off, keeping efficiency high across the full range of outdoor temperatures.
Exceptionally quiet operation
Tuned for exceptionally quiet running, allowing flexible installation even in restricted spaces.
Heating and active cooling
Active cooling by circuit reversal is available when paired with a compatible area heating system such as underfloor heating.
High flow temperature for retrofit
Supports flow temperatures up to 75 °C on the heating side, suitable for retrofit properties with radiators as well as new-build underfloor systems.
Smart, app-based control
Control via the MyStiebel app is possible with the ISG accessory, alongside Modbus/KNX integration for home automation and PV self-consumption.
Choose your capacity
| Model |
MPN |
Electrical supply |
Output (A-7/W35) |
SCOP 35°C |
Sound power |
| HPA-O 07.2 W Plus HC 230 |
208432 |
HC 230 (single-phase 230V) |
7.09 kW |
5.09 |
43 dB(A) |
| HPA-O 10.2 W Plus HC 230 |
208433 |
HC 230 (single-phase 230V) |
10.07 kW |
4.96 |
46 dB(A) |
| HPA-O 10.2 W Plus HC 400 |
208434 |
HC 400 (three-phase 400V) |
10.07 kW |
4.96 |
46 dB(A) |
| HPA-O 13.2 W Plus HC 400 |
208435 |
HC 400 (three-phase 400V) |
13.15 kW |
4.89 |
45 dB(A) |
Full technical specification
| Specification |
HPA-O 07.2 W Plus HC 230 |
HPA-O 10.2 W Plus HC 230 |
HPA-O 10.2 W Plus HC 400 |
HPA-O 13.2 W Plus HC 400 |
| Product number (MPN) |
208432 |
208433 |
208434 |
208435 |
| Electrical supply |
HC 230 (single-phase 230V) |
HC 230 (single-phase 230V) |
HC 400 (three-phase 400V) |
HC 400 (three-phase 400V) |
| SCOP 35°C (EN 14825) |
5.09 |
4.96 |
4.96 |
4.89 |
| SCOP 55°C (EN 14825) |
4.02 |
3.99 |
3.99 |
4.01 |
| Energy efficiency class, room heating |
A+++ |
– |
A+++ |
A+++ |
| Energy efficiency class, DHW heating |
– |
– |
A+++ |
– |
| Heating output at A2/W35 (EN 14511) |
3.29 kW |
4.09 kW |
4.09 kW |
4.82 kW |
| Heating output at A-7/W35 (EN 14511) |
7.09 kW |
10.07 kW |
10.07 kW |
13.15 kW |
| Cooling capacity at A35/W18 |
6.98 kW |
– |
10.02 kW |
13.00 kW |
| COP at A2/W35 (EN 14511) |
4.57 |
4.54 |
4.54 |
4.41 |
| COP at A-7/W35 (EN 14511) |
3.25 |
3.15 |
3.15 |
3.11 |
| Sound power level (EN 12102) |
43 dB(A) |
46 dB(A) |
46 dB(A) |
45 dB(A) |
| Min./max. application limits, heat source |
-25 / 40 °C |
-25 / 40 °C |
-25 / 40 °C |
-25 / 40 °C |
| Min./max. application limits, heating side |
15 / 75 °C |
15 / 75 °C |
15 / 75 °C |
15 / 75 °C |
| Height |
960 mm |
1144 mm |
1144 mm |
1365 mm |
| Width |
1170 mm |
1170 mm |
1170 mm |
1170 mm |
| Depth |
727 mm |
727 mm |
727 mm |
727 mm |
| Weight |
145 kg |
166 kg |
166 kg |
205 kg |
| Refrigerant |
R290 |
R290 |
R290 |
R290 |
| Colour |
Signal white RAL 9003 (fixed) |
Signal white RAL 9003 (fixed) |
Signal white RAL 9003 (fixed) |
Signal white RAL 9003 (fixed) |
– indicates a figure not separately published by the manufacturer for that model.
Smart control ready
Add the ISG accessory for MyStiebel app control and installer remote diagnostics, and integrate with Modbus or KNX for home automation and PV self-consumption.
Help us prepare your custom quote
Because Stiebel Eltron configurations are matched to the property, please have the following ready when requesting a quote:
-
System configuration – will the heat pump run as a stand-alone heat source, or in a bivalent arrangement alongside an existing boiler or secondary heat source?
-
Hot water demand – what is the expected DHW usage volume for the property (occupants, bathrooms, peak draw-off), or is DHW production not required?
-
Hydraulic layout – does the property use an S-plan or Y-plan hydraulic arrangement, or another zoned configuration?
-
Pre-plumbed preference – would a pre-plumbed cylinder/buffer assembly be preferred to reduce on-site installation time?
-
Secondary return – does the property require a secondary return circulation loop for the DHW system?
-
Installation restrictions – are there any size or positioning restrictions for the outdoor unit?
-
Electrical supply – is a single-phase (HC 230) or three-phase (HC 400) power supply available at the property?
-
Pump groups – how many pump groups are required downstream of the buffer on the secondary (heating distribution) side?
-
Control logic – should the system be controlled by the OEM heat pump manager, or integrated with a third-party room thermostat/BMS via Modbus or KNX?
Frequently asked questions
How is the W Plus range different from the standard HPA-O Plus range?
The W Plus range shares the same performance figures as the equivalent HPA-O Plus size, but is supplied with a fixed signal white (RAL 9003) casing and its own product number, rather than the anthracite/white colour choice on the standard Plus range.
What is the difference between HC 230 and HC 400 versions?
HC 230 units run on a single-phase 230V electrical supply, while HC 400 units require a three-phase 400V supply. The 10.2 output is available in both; 07.2 is HC 230 only and 13.2 is HC 400 only.
Is a cylinder included with these heat pumps?
No – this page covers the outdoor heat pump unit only, across all four capacities. Each is paired with a DHW cylinder, buffer volume and hydraulic kit selected to suit the property.
Why does this range use R290 instead of a common HFC refrigerant?
R290 (propane) is a natural refrigerant with a Global Warming Potential of around 3, compared with hundreds or thousands for many HFC refrigerants. It is mildly flammable, so installation clearances and ventilation requirements must be followed.
Can these heat pumps provide cooling as well as heating?
Yes. Active cooling is available by circuit reversal when the unit is paired with a compatible area heating system, such as underfloor heating.
Why is pricing shown as 'on request'?
Every installation is specified to the property, so pricing is confirmed once we know your configuration. Use the questions above or contact our technical team for a tailored quotation.
