NIBE · Heat-pump or fixed-AC model
S735
NIBE S735 is a current indoor exhaust-air heat pump combining space heating, hot water and mechanical extract ventilation, with UK 4 and 7 designations.
Specifications
| Specification | Value |
|---|---|
| Type | indoor exhaust-air heat pump with integrated hot-water cylinder |
| Refrigerant | R290 |
| UK designations | S735-4 and S735-7 |
| Dimensions (mm) | 2025 high x 600 wide x 620 deep |
| Published 40°C hot water litres | up to 264 |
NIBE S735 is a current indoor exhaust-air heat pump. It combines mechanical extract ventilation, space heating and domestic hot water in one cabinet and does not need an outdoor heat-pump unit. The UK range has S735-4 and S735-7 designations.
How it works
S735 combines mechanical extract ventilation, space heating and domestic hot water in one indoor cabinet. The integrated arrangement distinguishes it from an outdoor air-to-water heat pump.
Product details
The cabinet is 2,025 mm high, 600 mm wide and 620 mm deep. Its hot-water figure is up to 264 litres at 40°C. That is a mixed-water test quantity, not the physical cylinder volume or a guarantee for every draw pattern.
S735 uses R290 refrigerant. Its cabinet contains the refrigerant circuit, ventilation function and hot-water storage indoors rather than relying on a separate outdoor unit.
S735 is Quiet Mark certified in the UK.
System design
S735-4 and S735-7 are separate product designations. Their performance figures remain tied to the stated test basis and do not merge into one family-wide output.
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.