MasterTherm BoxAir Inverter P (6–20 kW)

Specifications and technical data

Air Source (ASHP)ResidentialR2906–20 kW

Manufacturer	MasterTherm
Model	BoxAir Inverter P
Model code	BA37IP-311U
Heat pump type	Air Source (ASHP) All Air Source heat pumps →
Application	Residential All Residential heat pumps →
Refrigerant	R290 All R290 heat pumps →
Mode	Heating only
Heating capacity	6–20 kW
Max heating output (low temp)	20 kW at A7/W35
SCOP (heating)	4.93 at W35
Operating range (air)	-20 to 40 °C
Heating flow temperature	up to 75 °C
Electrical supply	380-415V (Three Phase)
Dimensions (H×W×D)	1525 × 1313 × 620 mm
Sound power level	50 dB(A) (Sound Power LW(A))
Price (unit only)	~£11,281.60 (checked 2026-07-18 00:00:00)
Data added	2026-06-28
Data source	Manufacturer Data Sheet; Price: UK Retailer Pricing (thermalearth.co.uk), ex VAT shown
Verification	Verified by a human
MCS certification	✓ MCS listed
MCS listing	View on MCS ↗

Free data sheet (PDF) →

Check noise at a neighbour’s window (MCS 020 a) →

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MasterTherm BoxAir Inverter P is a 20 kW air source heat pump, providing heating and cooling, using R290 refrigerant.

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Data is compiled from manufacturer sources and may contain errors or gaps. Always confirm specifications with the manufacturer before making decisions.