NIBE · Heat-pump or fixed-AC model
S1155
NIBE S1155 is a current inverter-driven ground-source heat pump without an integrated hot-water cylinder; the UK range lists the S1155-25.
Specifications
| Specification | Value |
|---|---|
| Type | indoor inverter-driven brine-to-water ground source heat pump |
| Rated output (kW) | 12.68 at nominal B0/W35; 6 to 25 modulation range |
| Rated-output conditions | EN 14511, 0°C brine / 35°C flow, nominal operation |
| SCOP (seasonal coefficient of performance) at 35°C | 5.2 average climate; 5.5 cold climate |
| SCOP at 55°C | 4.0 average climate; 4.1 cold climate |
| Modulation range | 6 to 25 kW |
| Refrigerant | R410A |
| Sound power (dB) | 36 to 47 at B0/W35 |
| Warranty (years) | 2 standard; 7 through the qualifying NIBE Pro route |
| UK variant | S1155-25 |
| Energy label heating 35°C and 55°C | A+++ |
| Dimensions (mm) | 1500 × 600 × 620 |
| Weight (kg) | 205 |
| Integrated hot water cylinder | No |
| Connectivity | myUplink |
NIBE S1155 is an inverter-driven ground-source heat pump without an integrated domestic hot-water cylinder. The current UK range lists one designation, S1155-25.
Product arrangement
S1155 is an indoor brine-to-water unit without an integrated cylinder. Domestic hot water therefore requires a separate compatible cylinder.
S1155 uses NIBE’s S-Series control platform and supports myUplink monitoring and control. Its A+++ product and system energy classes apply at the defined 35°C and 55°C label conditions. They do not predict the seasonal performance of a particular ground array or building.
Design and warranty boundaries
The S1155-25 designation identifies the current UK model. Ground-array, flow-temperature and electrical design are installation-specific, so the designation and energy label do not establish those site values.
The standard guarantee runs for 24 months from installation or 33 months from manufacture, whichever is shorter. The seven-year NIBE Pro route requires registration within 28 days, a NIBE-trained installer, annual servicing and completed Benchmark documents. The applicable terms supplied with the unit still control a claim.
Related entries
Brand
Reference type
Heat-pump or fixed-AC model
Last reviewed
31 Jul 2026
Current status
Current in the manufacturer's UK range.