Baxi Indirect Cylinder

The Baxi Indirect cylinder is perfect for use with Baxi system or heat only boilers.

It delivers excellent water pressure for homes with higher demand for hot water, providing fast-filling baths and invigorating showers. The clever 'coil-in-coil' heat exchange inside means the water heats up extremely quickly, and the insulation means it is extremely energy efficient.

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Features and benefits    |    Dimensions    |    Product literature    |    Technical specifications   |   Related products   |   FAQs

Features and benefits


  125i 145i 170i 210i 250i 300i
A - Cold water inlet mm 355 355 355 356 356 355
B - Immersion heater mm N/A N/A N/A 900 1100 1418
C - T&P relief value mm 728 883 1008 1084 1309 1574
D - Height mm 1131 1258 1414 1516 1767 2081
Weight dry kg 34 38 41 41 51 54
Dimensions - Indirect
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Product literature

Technical specifications

  • Internal expansion with floating baffle
  • Insulated T and P valve
  • 50mm thick cylinder insulation
  • High grade duplex stainless steel
  • 76 litres per minute of hot water
  • 25-year warranty for complete peace of mind

  • View full specification
Units   125i 145i 170i 210i 250i 300i
Part number   7798178  7798179 7798180 7798181 7798182 7798183
Nominal capacity   125 145 170 210 250 300
Coil rating (@15l/min at 80 kW 11.6 11.8 12.5 12.8 13 11.8
Heat up times (@15l/min at 80 mins  31 35 40 45 54 65
Heat loss Kwh/24h  1.28 1.39 1.6 1.82 1.84 2.18
ErP rating   C C C C C C
Mix water delivery to 40°C litres 176 197 233 258 320 386
Max mains pressure bar 16
Max design pressure bar 8
Operating pressure bar 3
Max primary pressure bar 10
Expansion relief valve setting bar 8
T&P valve setting °C/bar
Immersion heater electrical rating kW @240V  3 3 3 3 3 3

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  • How to reset a Baxi boiler
  • How do I bleed a radiator?
  • How to recharge the air gap on a Megaflo unvented cylinder
  • How old is my boiler?
  • What is central heating sludge?

Read how to reset your boiler, whether it has a dedicated reset button, an ON/OFF/SELECTOR switch or a thermostat control knob.

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If you have cold spots at the top of your radiators, it means that there is trapped air that needs to be removed so your radiators will heat your room efficiently. Follow our simple steps for bleeding your radiators.

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If you've noticed that water is dripping from the safety pipe outside or through the tundish on the outside of your cylinder, this is an indication that the air gap in your cylinder needs recharging. Watch our video to find out how you can easily fix this yourself, without calling a heating engineer.

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We show you how to find out how old your boiler is from its serial number. 

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Sludge, or magnetite, to give it its proper name, is a black substance in the central heating pipes made up of dissolved and rusted metal. It forms when the water in the system reacts with the metal in radiators and pipes, and, if left to build up, it can damage your boiler and the system.

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