Baxi 100 Combi

 The new Baxi 100 Combi, from Plumb Center, is a compact but powerful new boiler addition to the Baxi family. It is small enough to fit into a standard 300mm deep cupboard, making it particularly suitable for homes where space is at a premium.

The Baxi 100 Combi is easy to maintain, delivers excellent flow rates and comes with a 2 year warranty*.

Baxi 100 Combi
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  • Available in outputs of 24kW and 28kW to suit most property types
  • Compact size that will fit inside a standard 300mm deep cupboard
  • User friendly controls and display
  • 2 year warranty as standard*
  • 32.5kg lift weight making it easy to transport, unpack and install
  • Easily accessible components for easy servicing
  • Industry leading choice of flue lengths, bends and accessories for versatile siting and easy replacement
  • Natural gas and LPG ready - no conversion kit required 

*Subject to registration and an annual service. Terms and conditions apply.

A: Boiler width = 390mm

B: Boiler height = 700mm

C: Boiler depth = 300mm

D: Side clearance = 5mm

E: Upper clearance = 175mm

F: Lower clearance = 170mm

G: Front clearance = 5mm in operation, 450mm for servicing

Baxi 100 Combi  124 Combi 128 Combi 
Sales Code

Boiler pack (boiler and standard flue)

Boiler only






Concealed User Controls    Yes Yes 
Operating mode selector switch with reset    Yes Yes 
User adjustable DHW temperature Range - 35° to 60° (±5ºC) Yes Yes 
User adjustable CH temperature   Range - 25° to 80° (±5ºC) Yes  Yes 
Temp/status/fault diagnosis display   LCD display  LCD display 
Baxi room thermostat   Optional  Optional  
RF Digital 7 Day Programmable Roomstat (Single Channel)    Optional  Optional 
Baxi Plug-In 24hr Digital timer-100   Optional  Optional 
Nest Learning Thermostat   Optional   Optional 
Multifit Outdoor Sensor Kit   Optional   Optional 
Stand Off Kit - Compact   Optional   Optional 
Remote Secondary PRV Kit   Optional   Optional 
Filling Loop Kit   Optional   Optional 
SAP 2009 Annual Efficiency (PCDB/SEDBUK)  % 89.1  89.1 
NOx class   
ErP Product Information 
NOx mg/kWh 15 17
Sound Power Level, Indoors  LWA dB 49 50 
Space Heating Efficiency Class   
Water Heating Declared Load Profile    XL  XL 
Water Heating Efficiency Class   
Heat Input CH kW max gross (QnHs) 20.2  26.6 
kW min gross (QnHs)  3.8 4.3 
Heat Output CH (non condensing)   kW (Pn) 20 24 
 kW (Pn) 3.4 3.8
Heat Output CH (condensing) kW max (PnC)          21.2  25.3 
kW min (PnC)  3.7 4.1 
Gas supply pipe size  (mm)  22  22 
Inlet supply pressure (natural gas) mbar (nominal) 20 20
Maximum gas rate (natural gas after 10 mins)   m3/hr  2.61  3.05
Mechanical and hydraulic  
Heat input domestic hot water (DHW) kW max gross (QnwHs) 27.4  32.1 
Heat output domestic hot water kW max  24 28 
Maximum DHW flow rate (Delta T @ 35ºC max) l/min  9.8 11.5
Minimum DHW flow rate required l/min   2.0 2.0 
Minimum operating DHW pressure required bar  0.15 0.15
Maximum DHW system pressure bar  8 8
Safety discharge pressure bar  3.0 3.0
Compartment ventilation required No No 
Flow / return pipe size (mm)  22  22 
Integral expansion vessel   Size (litres)  6
CH system inhibitor required    Yes  Yes 
Condensate discharge pipe size   (mm)  21.5  21.5 
Electrical supply   Volts/Hz  230V/50Hz  230V/50Hz  
Permanent live required     Yes  Yes 
Electrical power cable required core   3 x 0.75 3 x 0.75 
Power consumption when firing   Watts  85                 90 
External fuse rating Amps 
Internal fuse rating   AH  F2L  F2L 
Boiler IP rating (electrical protection) without integral timer fitted  Approval category   IPX5D  IPX5D 
Circulating pump exercise feature     Yes  Yes 
Pump overrun     Yes  Yes 
Integral 'boiler only' frost thermostat    Yes  Yes 
Concentric flue system 
Standard telescopic concentric flue Length in mm 315-500  315-500 
Horizontal concentric (60/100 mm)  Max equivalent length (m)  10  10 
Reduction per 135° bend (m)  0.5  0.5 
Reduction per 93° bend (m) 
Horizontal concentric (80/125mm)  Max equivalent length 20 20
Horizontal twin tube (80/80mm)   Reduction per 135° bend (m)  0.25  0.25 
Reduction per 93°bend (m)   0.5  0.5 
Installer lift weight (boiler) Max (kg)  32.5  32.5
Gross packaged boiler weight  (kg)  36.5 36.5

Additional heating and hot water accessories can improve the overall efficiency and performance of your heating system. This could reduce your fuel consumption and your energy bills.

For more information on any of the below accessories please speak to your installer as they will be able to advise you on the controls that are right for you.

Baxi wired weather sensor

Baxi room thermostat

Digital 7 day programmable roomstat

Baxi Plug-in 24hr digital timer


You can download product information on the Baxi 100 here:


  • Baxi 100 Combi Range Guide (PDF 3.64MB, 09/08/2017)
  • Baxi 100 Installation Guide (PDF 17.37MB, 22/05/2017)
  • Baxi 100 User Guide (PDF 2.76MB, 22/05/2017)
  • We don't sell our products directly to consumers which is why our prices aren't on our website.

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