Expansion Tanks & Vessels

At Toolstation, we stock a wide range of feed and expansion tanks from trusted brands like RM Cylinders, Tesla, Polytank and Ariston. Whether you need a 5L expansion tank, 25L hot water storage tank, immersion heater, thermostat, ball valve or tank jacket, we’ve got plenty of products to choose from.

What is a Central Heating Expansion Tank Used For?


Central heating tanks are an essential component for most domestic systems, helping to maintain the correct pressure throughout the system. Expansion vessels work similarly to an overflow tank, allowing excess water or air to be stored as the system heats and cools.

All boilers are already fitted with an expansion tank, but they may need replacing if you frequently experience pressure loss, leaving you without heating or hot water. Browse our full selection of central heating expansion tanks here and find high-quality replacement parts.
Ariston Ariston / Ariston Andris Expansion Vessel & Non-Return Valve KIT A
20% Off
( 11 )

£43.82 was £54.78

ex. VAT £36.52 Each

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Out of stock for delivery

Water Tank Jacket 50 Gallon
( 76 )

Product code: 61470

Water Tank Jacket 50 Gallon

£22.38

ex. VAT £18.65 Each

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Ball Valve Pack
( 110 )

Product code: 18984

Ball Valve Pack

£15.58

ex. VAT £12.98 Each

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Zilmet Zilmet / Expansion Vessel 8L
( 21 )

Product code: 29704

Expansion Vessel 8L

£24.98

ex. VAT £20.82 Each

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Heatrae Sadia Heatrae Sadia / Heatrae Sadia Megaflo Eco Direct Cylinder 210L

£1276.98

ex. VAT £1064.15 Each

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Zilmet Zilmet / Expansion Vessel 18L
( 68 )

Product code: 64278

Expansion Vessel 18L

£34.98

ex. VAT £29.15 Each

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Zilmet Zilmet / Expansion Vessel 25L
( 68 )

Product code: 72473

Expansion Vessel 25L

£39.98

ex. VAT £33.32 Each

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Expansion Vessel Control Kit
( 8 )

Product code: 49934

Expansion Vessel Control Kit

£53.88

ex. VAT £44.90 Each

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Joule Joule Joule / Joule Invacyl Slimline Direct Unvented Cylinder 180L

£609.98

ex. VAT £508.32 Each

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Zilmet Zilmet / Expansion Vessel 12L
( 68 )

Product code: 70204

Expansion Vessel 12L

£29.98

ex. VAT £24.98 Each

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Joule Joule Joule / Joule Invacyl Slimline Indirect Unvented Cylinder 210L

£704.98

ex. VAT £587.48 Each

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Heatrae Sadia Heatrae Sadia / Heatrae Sadia Megaflo Eco Direct Cylinder 300L

£1449.98

ex. VAT £1208.32 Each

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5 Panel Cylinder Jacket 42 x 18"
10% Off
( 77 )

£20.68 was £22.98

ex. VAT £17.23 Each

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Joule Joule Joule / Joule Invacyl Unvented Direct Cylinder 120L

£493.98

ex. VAT £411.65 Each

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Joule Joule Joule / Joule Invacyl Slimline Indirect Unvented Cylinder 180L

£703.98

ex. VAT £586.65 Each

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Joule Joule Joule / Joule Invacyl Unvented Indirect Cylinder 210L

£647.98

ex. VAT £539.98 Each

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For delivery only

Joule Joule Joule / Joule Invacyl Unvented Indirect Cylinder 250L

£699.98

ex. VAT £583.32 Each

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Water Storage Tank LWH: 442 x 296 x 305mm 4 Gallon
( 69 )

£10.28

ex. VAT £8.57 Each

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Joule Joule Joule / Joule Invacyl Unvented Direct Cylinder 210L
( 1 )

£555.98

ex. VAT £463.32 Each

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Tesla Tesla / Tesla Long Life Incoloy Immersion Heater & Resettable Thermostat 27"
( 103 )

£29.38

ex. VAT £24.48 Each

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Byelaw 30 Tank Kit 4 Gallon
( 20 )

Product code: 37570

Byelaw 30 Tank Kit 4 Gallon

£24.98

ex. VAT £20.82 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Direct Unvented Hot Water Cylinder 1980 x 545 300L

£692.98

ex. VAT £577.48 Each

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Joule Joule Joule / Joule Invacyl Slimline Direct Unvented Cylinder 120L

£591.98

ex. VAT £493.32 Each

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Tesla Tesla / Tesla Long Life Incoloy Immersion Heater & Resettable Thermostat 11"
( 45 )

£26.23

ex. VAT £21.86 Each

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