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geoTHERM 22kW, 30kW, 38kW and 46kW (discontinued)

Ground source heat pump

  • "Quiet Mark" accredited thanks to geoTHERM multi-stage sound insulation
  • Energy yield display
  • MCS accredited, RHI eligible


Attention: This product is now discontinued.

Vaillant’s geoTHERM range of ground source heat pumps provides maximum comfort and efficiency, combined with simple installation, smooth operation and advanced diagnostics that have become synonymous with the Vaillant brand. geoTHERM is compatible with domestic, and with a range of larger outputs, can serve commercial properties or large homes which operate on a three-phase electricity supply.

As part of a well-insulated home, the geoTHERM system provides the perfect solution for off-gas properties, using oil or LPG in particular, by accessing a sustainable energy source, helping to protect against fluctuating prices of fuel, and also eliminating the need for fuel storage.

geoTHERM was the first heat pump to be “Quiet Mark” accredited from Vaillant, which was quickly followed by the air source heat pump, aroTHERM and the ground source heat pump, flexoTHERM 230V and 400V.

Features and benefits

  • Models are available in four outputs 22kW, 30kW, 38kW and 46kW
  • Evaporator with injection system - provides increased heat transfer
  • Maximum flow temperature of up to 62°C for domestic hot water
  • Weather-compensated energy-balance control unit with graphic display of the environmental yield. The inbuilt control shows in a clear bar chart diagram showing the energy absorbed from the ground loop, proving the actual system efficiency
  • Multi-stage Sound Insulation (MSI) for quiet operation
  • Passive cooling function
  • Available to use in cascade
  • Works efficiently with low floor temperature heating systems, either underfloor or radiators sized to suit
  • MCS accredited and RHI eligible
  • Commissioning available by Vaillant Service



Heat pump type Brine/Water heat pump
Product-side flow/return heating connections  G1 ½”G1 ½”G1 ½”G1 ½”
Product-side flow/return heat source connections G1 ½”G1 ½”G1 ½”G1 ½”
Product dimensions, heating without connectionmm1200120012001200
Product dimensions, widthmm760760760760
Product dimensions, depth without column mm900900900900
Weight, with packaging kg356370394417
Weight, without packaging kg326340364387
Weight, ready for operation kg341359386414
Permissible ambient temperature  7 .. 27 .. 27 .. 27 .. 2
Heat exchanger performance data The following performance data is applicable to new products with clean heat exchangers
Heating output B0/W35 T 5KkW21.530.937.745.5
Power consumption B0/W35 T 5KkW4.86.78.410.0
Output figures B0/W35 T 5K/coefficient of performance EN 14511
Power consumption B0/W55 T 8KkW20.128.334.641.4
Power consumption B0/W55 T 6K without pumps kW6.28.91113
Output figures B0/W55 T 8K/coefficient of performance En 14511
Sound level B0/W35 En 12102/EN14511 dB(A)54555661
Application limits: At the same volume flow rates as for the nominal output test under standard nominal conditions with nominal flows and brine circuit T 3K/heating circuit T 5K. Operation of the pump outside the application limits results in the heat pump being switched off by the internal control and safety device

Brine fluid: Ethylene glycol/water ratio 3/73/73/73/7
Maximum brine fluid operating pressureMPa
Minimum source inlet temperature (hot brine) in heating mode°C -10-10-10-10
Maximum source inlet temperature (hot brine) in heating mode°C 20202020
Volume of the heat source circuit in the heat pump l6.28.610.012.4
Nominal flow at T 3Km3/h5.17.68.510.7
Minimum permissible volume flow m3/h3.
Maximum permissible volume flow m3/h5.58.39.311.8
Pressure loss with nominal flow at T 3KkPa22.
Materials Cu
CuZn alloy
Stainless steel
Maximum heating circuit operating pressureMPa
Minimum heating mode flow temperature°C 25252525
Maximum heating mode flow temperature°C 62626262
Heating circuit water contents in the heat pump l8.310.312.014.1
Nominal flow at T 5Km3/h3.
Minimum permissible volume flow m3/h2.
Maximum permissible volume flow m3/h4.
Pressure loss with nominal flow at T 5KkPa7.29.311.020.0
Materials  Cu
CuZn alloy
Stainless steel
Refrigerant type  R 407 CR 407 CR 407 CR 407 C
Refrigerant content for the refrigerant circuit in the heat pump kg4.105.996.708.60
Maximum operating pressure: refrigerant MPa
Compressor type  Scroll ScrollScrollScroll
Oil type  Ester (EMKARATE RL-32-3MAF)
Oil filling quantityl4.
Rated voltage of the compressor/heating circuit  3/NE/PE 400 V 50 Hz
Control circuit rated voltage 1~N/PE 230 V 50 Hz
Rated voltage of the auxiliary heater (on-site) 3/N/PE 400 V 50 Hz
Phase shifting  cos = 0.7 to 0.84cos = 0.72 to 0.83cos = 0.76 to 0.86cos = 0.75 to 0.86
Required network impedance Zmax with in-rush current limiterA0.4720.4500.2700.100
Fuse type, characteristic C, slow-blow, three-pole switching (disconnection of the three mains connection lines in one switching operation)A20253240
Optional on-site residual-current circuit breaker RCCB type A (type A pulse-current-sensitive residual-current circuit breakers) or RCCB type B 9type B universal-current-sensitive residual- current circuit breakers)
In-rush current without in-rush current limiterA99127167198
In-rush current with in-rush current limiterA446585110
Minimum electrical power consumption for B5/W35kW5.06.48.510.1
Maximum electrical power consumption for B20/W60kW10.
Maximum electrical power consumption for auxiliary heaterkW3 x 2.33 x 2.33 x 2.33 x 2.3
EN 60529 level of protection IP 10BIP 10BIP 10BIP 10B

Related Products

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Heat pump cylinders

  • Complete with three-way valve and adapter, making it easier and saving time on install.
  • Comes with unvented kits and expansion vessel
  • Inline front connections, reducing piping issues in smaller, more compact areas


Alternative products

Alternative products

aroTHERM air source heat pump

  • Blue fin coated evaporator as standard
  • Monobloc hermetically sealed air to water heat pump
  • Ready for future European legislation

aroTHERM hybrid air source heat pump

  • MCS accredited
  • Suitable for domestic and commercial properties
  • Compatible with all boiler systems including gas, LPG and oil

flexoTHERM 230V 5kW, 8kW and 11kW

  • Connects to two different sources - Ground or water
  • ErP rated A+++ when installed with VRC 700 or VRC 700f
  • "Quiet Mark" accredited by the Noise Abatement Society

flexoTHERM 400V 5, 8,11,15 and 19kW

  • Connects to three different sources - ground, water or air
  • ErP rated A+++ when installed with VRC 700
  • "Quiet Mark" accredited by the Noise Abatement Society