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.
RM Cylinders RM Cylinders RM Cylinders / Indirect Hot Water Cylinder 900 x 450 117L
( 51 )

£274.97

ex. VAT £229.14 Each

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Ariston Ariston / Ariston Andris Expansion Vessel & Non-Return Valve KIT A
( 10 )

£68.98

ex. VAT £57.48 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Indirect Unvented Hot Water Cylinder 1720 x 545 250L
Save £67

£805.98 was £873.08

ex. VAT £671.65 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Indirect Unvented Hot Water Cylinder 1100 x 545 150L
Save £114

£608.98 was £722.98

ex. VAT £507.48 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Indirect Unvented Hot Water Cylinder 1470 x 545 210L
Save £68

£769.98 was £837.98

ex. VAT £641.65 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Direct Unvented Hot Water Cylinder 1720 x 545 250L
Save £60

£631.98 was £692.38

ex. VAT £526.65 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Direct Unvented Hot Water Cylinder 1280 x 545 180L
Save £78

£599.98 was £678.38

ex. VAT £499.98 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Indirect Unvented Hot Water Cylinder 1280 x 545 180L
Save £132

£648.98 was £781.88

ex. VAT £540.82 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Direct Unvented Hot Water Cylinder 1980 x 545 300L
Save £65

£692.98 was £758.28

ex. VAT £577.48 Each

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Zilmet Zilmet / Expansion Vessel 12L
( 59 )

Product code: 70204

Expansion Vessel 12L

£29.98

ex. VAT £24.98 Each

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RM Cylinders RM Cylinders / RM Optimum Stainless Steel Direct Unvented Hot Water Cylinder 1100 x 545 150L
Save £94

£549.98 was £643.98

ex. VAT £458.32 Each

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Ball Valve Pack
( 90 )

Product code: 18984

Ball Valve Pack

£15.58

ex. VAT £12.98 Each

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Zilmet Zilmet / Expansion Vessel 18L
( 59 )

Product code: 64278

Expansion Vessel 18L

£34.98

ex. VAT £29.15 Each

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Zilmet Zilmet / Expansion Vessel 8L
( 16 )

Product code: 29704

Expansion Vessel 8L

£24.98

ex. VAT £20.82 Each

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Water Tank Jacket 50 Gallon
( 72 )

Product code: 61470

Water Tank Jacket 50 Gallon

£22.38

ex. VAT £18.65 Each

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TESLA TESLA / T-BAR Expansion Vessel Fixing Bar Kit
( 1 )

£44.98

ex. VAT £37.48 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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4 Panel Cylinder Jacket 42 x 18"
( 70 )

£22.38

ex. VAT £18.65 Each

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Byelaw 30 Tank Kit 4 Gallon
( 17 )

Product code: 37570

Byelaw 30 Tank Kit 4 Gallon

£24.98

ex. VAT £20.82 Each

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Water Storage Tank LWH: 442 x 296 x 305mm 4 Gallon
( 59 )

£10.28

ex. VAT £8.57 Each

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Expansion Vessel Bracket 5 to 24L
( 7 )

£18.98

ex. VAT £15.82 Each

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Storage Tank Lid 4 Gallon
( 34 )

Product code: 67700

Storage Tank Lid 4 Gallon

£4.18

ex. VAT £3.48 Each

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4 Panel Cylinder Jacket 36 x 18"
( 77 )

£16.68

ex. VAT £13.90 Each

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Storage Tank Lid 25 Gallon
( 6 )

Product code: 47335

Storage Tank Lid 25 Gallon

£19.57

ex. VAT £16.31 Each

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