Baxi Megaflo System

The Baxi Megaflo System boiler combines high efficiency and excellent environmental credentials with performance and style.  For homes with a high demand for hot water, or with more than one bathroom, it will satisfy all your hot water requirements while heating your home.

It has the highest SEDBUK Band 'A' rating, so it will reduce your energy bills compared with old, standard efficiency boilers, and lower your carbon emissions.

The Baxi Megaflo System is now available with a 7 year warranty when registered before 31st December 2017*.

Megaflo System
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*Subject to registration before 31st December 2017 and an annual service. Terms and conditions apply.

Megaflo system HE A clearance

A: Boiler width = 450mm

B: Boiler height = 780mm

C: Boiler depth = 345mm

D: Side clearance = 5mm

E: Upper clearance = 200mm

F: Lower clearance = 150mm

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

View product specification

When clicked this will open the product specification in PDF format.

15 System 18 System  24 System 28 System 32 System
Sales code 7219444 7219445 7219446 7219447 7219448
Concealed user controls   Yes Yes Yes Yes Yes
On/off switch with reset   Yes Yes Yes Yes Yes
User adjustable CH temperature Yes Yes Yes Yes Yes
LED temp / status / fault diagnosis display

2 digits / 3 LEDs on all models

Gas supply connection   mm 22 22 22 22 22
Natural gas   Yes Yes Yes Yes Yes
Nominal inlet supply pressure mbar 20 20 20 20 20
Maximum inlet supply pressure m3/hr  1.69 1.95 2.61 3.1 3.48
Heat input central heating kW max gross (QnHs) 17.1 20.5 27.4 32.1 36.4
kW min gross (QnHs) 4.4 4.8 7.8 10.8 10.8
Heat output CH non condensing kW max (Pn) 15 18 24 28 32
kW min (Pn) 3.9 4.2 6.8 9.4 9.4
Heat out CH condensing kW max (Pnc) 16.2 19.4 25.9 30.3 34.4
kW min (Pnc) 4.2 4.5 7.4 10.2 10.2
SAP 2009 Annual Efficiency (PCDB/SEDBUK) % 88.6 88.6 88.6 88.5 88.5
NOx class   5
ErP Product Information
NOx mg/kWh 25 29  20  20  24 
Sound power level, indoors Lwa dB 52 53  58  53  54 
Space heating efficiency class
Electrical supply Volts/Hz 230V/50hz 230V/50hz  230V/50hz  230V/50hz  230V/50hz 
Permanent live required   Yes  Yes  Yes   Yes   Yes  
Fitted electrical cable  

1m x 3 core x 0.75mm2 on all models

Power consumption Watts  130  140  150  160  160 
External fuse rating Amps 
Internal fuse rating Amps  F2L  F2L  F2L   F2L   F2L  
Ingress protection rating
(without electro-mechanical timer fitted)
  IPX 5D IPX 5D  IPX 5D  IPX 5D  IPX 5D 
24 hour pump exercise   Yes  Yes   Yes   Yes   Yes 
Pump overrun   Yes  Yes   Yes   Yes   Yes  
Integral 'boiler only' frost thermostat   Yes  Yes   Yes   Yes   Yes  
Mechanical and hydraulic
Compartment ventilation requirement   None None  None  None  None 
Pre-plumbing / wall mounting jig   Yes Yes Yes  Yes  Yes 
Flow and return pipe size mm 22 22  22  22  22 
Condensate discharge pipe size mm 21.5  21.5   21.5   21.5   21.5  
Integral automatic bypass   Yes  Yes   Yes Yes   Yes  
Safety discharge pressure bar
Integral expansion vessel litres 8 8 10  10 
Max capacity of central heating system litres  125  125  125  125  125 
CH system inhibitor required   Yes Yes  Yes  Yes  Yes 
Concentric Flue System
Standard horizontal flue kit length mm  685  685   685   685   685 
Max equiv length horizontal / vertical (60/100mm) 10  10  10   10   10  
Max equiv length horizontal / vertical (80/125mm) 20  20   20   20   20  
Equivalent length per 135o bend m 0.5  0.5  0.5  0.5  0.5 
Equivalent length per 93o bend m
Twin pipe flue system
Diameters mm 80/80  80/80   80/80   80/80   80/80 
Max equiv length horizontal / vertical (parallel pipes) 15/15 15/15  15/15  15/15  15/15 
Equivalent length per 135o bend m 0.25 0.25 0.25  0.25  0.25 
Equivalent length per 91.5o bend m 0.5 0.5  0.5  0.5  0.5 
Max installation lift weight kg 36.4 36.4  37.9  37.9  38.4 
Gross packaged boiler weight kg 41.5 41.5 43  43  43.5 
  • Pre-plumbing jig, complete with pre-formed copper pipe tails, built in filling loop and 1 metre mains cable to save the installer time and money during installation
  • Compatible with Multifit flue kits, which provide an industry leading choice of lengths, bends and accessories, allowing for versatile siting
  • Front access to all components for straightforward and quick servicing
  • Free of charge Baxi product training throughout the UK
  • Free Gas Safe notification and warranty registration online, saving you time and money on any Baxi boiler you install through the works loyalty scheme

The Baxi Megaflo System is compatible with a range of accessories & and products ensuring even greater efficiency and energy saving.

  • Baxi Solarflo thermal range using free energy from the sun to generate hot water
  • Megaflo Eco and Megaflo Eco Solar hot water storage cylinders
  • Baxi room thermostat which can achieve additional savings of £70 and 280 kg carbon dioxide a year according to Energy Saving Trust.


Baxi's system boiler range comes with product literature for homeowners and installers alike. To learn more about the features the Baxi Megaflo has to offer, plus gain knowledge of the boiler, download our documents.

  • Megaflo System ErP homeowner guide (PDF 0.82MB, 22/01/2016)
  • Baxi Platinum, Duo-tec and Megaflo ErP range guide (PDF 2.73MB, 14/06/2017)
  • Baxi Megaflo System ErP user guide (PDF 1.62MB, 05/01/2016)
  • Baxi Megaflo System ErP installation and servicing manual (PDF 9.86MB, 24/05/2017)
  • We don't sell our products directly to consumers which is why our prices aren't on our website.

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