Warmflow G-Series ground source (4.5–18 kW)

Specifications and technical data

✓ BUS eligibleGround Source (GSHP)ResidentialR410A4.5–18 kW

Manufacturer	Warmflow
Model	G-Series ground source
Model code	GS16
Heat pump type	Ground Source (GSHP) All Ground Source heat pumps →
Application	Residential All Residential heat pumps →
Refrigerant	R410A All R410A heat pumps →
Mode	Heating only
Heating capacity	4.5–18 kW
Max heating output (low temp)	11.63 kW at B0/W35
COP (heating)	5.08 at B0/W35
Heating flow temperature	30–65 °C
Electrical supply	220-240V (Single Phase)
Dimensions (H×W×D)	890 × 590 × 660 mm
Operational Weight	130 kg
Sound power level	55 dB(A) (Sound Power LW(A))
Data added	2026-10-21
Data source	Warmflow G-Series ground source heat pump manual v6
Verification	Verified by a human
Boiler Upgrade Scheme	✓ BUS eligible — Listed on the Ofgem BUS Product Eligibility List (24 Sep 2026). Grant also needs an MCS-certified installer and a qualifying system design. Funding guide
PEL certificate no.	BSI KM 612798/2
MCS certification	✓ MCS listed
MCS certificate no.	BSI KM 612798/2

Free data sheet (PDF) →

Warmflow GS16 variable-speed ground source heat pump, 4.5-18 kW, R410A, flow up to 65 °C, single-phase 230 V.

Where to buy (UK)

UK Supplier	Plumbnation
UK Supplier	Inspired Heating
UK Supplier	Wolseley
UK Supplier	City Plumbing
UK Supplier	HVAC-Sanitary

✎ Suggest a correction to this data

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