Photo: Weishaupt
Air/water splitR410A
Weishaupt Splitblock WSB 12 / 15 / 18 (R410A)
Air-to-water split · 3 models · DE, AT, CH
The larger Splitblock sizes for buildings up to about 18 kW heat demand, with R410A, three-phase compressor and the same wall-hung hydraulic unit (2 x 3.5 kW heater). Output is the A2/W35 modulation range; sound power is the A7/W55 day rating.
Grant lists
Grants depend on the exact model being on the official list. The counts below are the entries of this series we found in each list.
BAFA WEP (Germany)
3 models listed
3 models of this series are eligible in the BAFA Wärmeerzeuger-Portal, the list the German BEG heat pump grant depends on.
checked November 4, 2026 · See the entries
ZUM (Poland)
No model on the list
No model of this series is on the Lista ZUM, so it cannot be funded under Czyste Powietrze.
checked November 4, 2026
Specifications
| Type | Air-to-water split |
|---|---|
| Heating output (datasheet) | 3.4–15.3 kW |
| Design heat load Pdesignh (35 °C) | 8.5–12.1 kW |
| SCOP at 35 °C | 4.19–4.46 |
| SCOP at 55 °C | 3.23–3.4 |
| Refrigerant | R410A (GWP 2088) |
| Outdoor sound power | 61–65 dB(A) |
| Max. flow temperature | 60 °C |
| Built-in backup heater | 7 kW |
| Markets | DE, AT, CH |
Heating output is the figure in the manufacturer's datasheet; the basis (nominal output at A7/W35 or B0/W35, or design heat load) differs between brands, so check the datasheet before comparing. * = design heat load Pdesignh at 35 °C from the BAFA portal.
Control and connectivity
| SG Ready | Yes |
|---|---|
| Modbus | Yes (TCP) |
| EEBUS | Not documented |
| Cloud API | not confirmed (WEM Portal) |
| §14a EnWG control | not confirmed |
| Local interfaces | SG Ready, Modbus TCP |
Source: www.weishaupt.de/uploads/tx_weishaupt_documents/documents... · www.weishaupt.de/uploads/tx_weishaupt_documents/documents... · www.weishaupt.de/uploads/tx_weishaupt_documents/documents...
Zerofy
Via SG ReadyZerofy has no native Weishaupt integration yet, but this series has an SG Ready input: Zerofy can switch it through a Shelly relay on the SG Ready terminals.
Models in this series
Model codes as the manufacturer documents them. The official list entries, with their own naming, follow below.
Models on the BAFA list 3
Eligible in the BAFA Wärmeerzeuger-Portal on November 4, 2026. Anlagennummer is the entry's number in the portal; SCOP at 55 °C is derived from the portal's ηs value.
| Model | Anlagennummer | SCOP 35 °C | SCOP 55 °C | Sound | Refrigerant | SG Ready |
|---|---|---|---|---|---|---|
| WSB 12-A-RMD-AI | 16011451 | 4.32 | 3.4 | 60.0 dB(A) | R410A | Yes |
| WSB 15-A-RMD-AI | 16011452 | 4.46 | 3.23 | 65.0 dB(A) | R410A | Yes |
| WSB 18-A-RMD-AI | 16011453 | 4.19 | 3.31 | 65.0 dB(A) | R410A | Yes |
Entries as published in the official lists on the date shown; names and numbers are copied verbatim. Check the list for your exact model before you order.
More Weishaupt heat pumps
Sources
- Datasheet: www.weishaupt.de/uploads/tx_weishaupt_documents/documents/83601001.pdf
- Product page: www.weishaupt.de/produkte/waermepumpen-solar/weishaupt-splitwaermepumpe
- Control and connectivity: www.weishaupt.de/uploads/tx_weishaupt_documents/documents/83601001.pdf
- Control and connectivity: www.weishaupt.de/uploads/tx_weishaupt_documents/documents/83805902.pdf
- Control and connectivity: www.weishaupt.de/uploads/tx_weishaupt_documents/documents/83807301.pdf
- BAFA Wärmeerzeuger-Portal – Wärmepumpen – checked November 4, 2026
- Lista ZUM (Instytut Ochrony Środowiska) – checked November 4, 2026
- EEBUS certified devices – checked November 2, 2026
All figures are taken from the manufacturers' datasheets and the official BAFA and ZUM lists on the date shown and may have changed since. This is not grant advice – check the list and your grant conditions before you order. Zerofy is not affiliated with any of the manufacturers listed.
SG Ready is a label of the Bundesverband Wärmepumpe (BWP) e.V.; “Yes” means the manufacturer documents the two-input interface or declares it on the BAFA portal, not that the series carries the BWP label – the label list is at waermepumpe.de. EEBUS is a standard of the EEBus Initiative e.V.; Modbus is a registered trademark of Schneider Electric, licensed to the Modbus Organization. Product names, logos and photos belong to their manufacturers and are shown to identify the products. Grant data: BAFA Wärmeerzeuger-Portal and Lista ZUM (IOŚ-PIB) as of the dates shown; the SCOP at 55 °C in the BAFA tables is calculated by Zerofy from the portal's ηs value.
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