5 kw Heat Pump

As a general guide, a 5 kW unit suits a small to medium home of around two to three bedrooms with a reasonable insulation standard. Its 2.0 to 6.0 kW modulation range gives useful flexibility across mild and peak conditions. Floor area alone is not a reliable indicator, because insulation quality, window area and glazing, ceiling height, local climate, and whether the unit also supplies hot water all affect the heat load. A poorly insulated three-bedroom property may need more capacity than a well-insulated four-bedroom one, so a heat loss calculation by a qualified installer is the only dependable basis for the decision.

It achieves a COP of 4.5 at A7/W35 test conditions, delivering 5 kW of heat from 1.11 kW of electrical input, and carries an ERP rating of A+++ at 35°C and A++ at 55°C. For domestic hot water the COP is 4.4. The figure you achieve in service depends most on flow temperature, and this unit's own data shows the effect clearly: COP falls from 4.5 at 35°C water to 3.6 at 45°C. Outdoor temperature and building insulation are the other two determining factors.

For a small to medium home, yes, and underfloor heating is the most efficient application for it. Underfloor systems run at 30 to 45°C flow temperature, which is where this unit reaches its highest COP of 4.5. What also matters is that the underfloor system itself is designed to deliver the required output at those temperatures, which depends on pipe spacing, screed depth, and floor covering. Confirm the floor's output capability alongside the heat pump capacity rather than treating them separately.

Yes. The unit is reversible and delivers 4 kW of cooling capacity at A35/W7 conditions with an EER of 2.85, running the same refrigeration cycle in the opposite direction. One unit therefore covers both seasons. If the system feeds underfloor heating, note that radiant cooling requires attention to condensation risk, since surfaces cooled below the dew point attract moisture. This is manageable with correct control but belongs in the system design rather than added afterwards.

The 5 kW unit is rated at ≤52 dB(A), making it the quietest model in the Legom range, helped by its single low-noise axial fan and brushless DC motor. Placement still matters more than the rating alone: position the unit away from bedroom windows and avoid siting it in a corner where sound reflects off two surfaces. The DC inverter compressor also contributes here, since modulating output produces steadier sound than a fixed-speed unit repeatedly starting and stopping.

The unit is engineered to keep operating down to -35°C ambient, which covers the great majority of populated cold-climate regions. Output does decrease as temperature falls, which applies to every air source heat pump, so cold-climate projects should be sized against the local design temperature rather than the nominal rating. The intelligent demand-based defrost system matters here too, since frequent ineffective defrost cycles are what typically undermines cold-weather comfort in simpler units.

R32 has a Global Warming Potential of 675 against R410A's 2088, just 32% of it. Its lower liquid density means a smaller refrigerant charge is needed for the same system, and the greater heat required to evaporate R32 means a smaller mass flow rate per unit and a higher COP. There is also a commercial consequence: high-GWP refrigerants face progressive restriction under the European F-Gas Regulation and equivalent rules elsewhere, which makes equipment charged with them harder and more costly to service over time.

The 5 kW unit measures 1065 × 405 × 710 mm (W × D × H) and weighs 60 kg net, making it the most compact and lightest model in the range. Packing dimensions are 1200 × 480 × 750 mm. Water connections are G3/4 DN20 with a water yield of 1.03 m³/h and a pressure loss of 20 kPa. Note that no expansion tank is included with this model, unlike the 16 kW unit which includes a 5 litre tank, so allow for one in the system design.

Eleven cabinet finishes are available: white, white grey, grey, black, blue, green, red, yellow, gold, brown, and mocca. This range exists for two reasons. For OEM and private-label partners, cabinet colour is part of brand identity. For residential projects, the outdoor unit is often visible from a garden or terrace, and matching it to the building rather than accepting a default white is a meaningful specification option. Colour is one of the customization parameters available on OEM orders alongside logo, nameplate, and packaging.

Yes. OEM and ODM customization covers cabinet colour across eleven available finishes, logo and nameplate, packaging, and controller and operating parameter configuration for private-label supply. Samples are produced and performance tested against your specification before production commitment, and performance and leak test records are available for production batches. All projects are handled under confidentiality agreement. Contact the technical team with your target market and volumes to discuss terms.

The unit is CE and RoHS certified and carries an ERP energy label rating of A+++ at 35°C and A++ at 55°C. CE confirms compliance with applicable European safety, electromagnetic compatibility, and low voltage requirements, and RoHS confirms restriction of hazardous substances in electronic components. Certification documentation is available on request for regulatory submission and procurement compliance. Confirm any additional market-specific requirements for your destination, since certification obligations depend on where the product is sold rather than where it is manufactured.