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Altecnic Robokit Extra, 18L Nitrogen Filled, Sealed System Kit

£67.74 £56.45
In stock
Available for back-ordered delivery
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A closed or sealed heating system must include a sealed system kit consisting of an expansion vessel and other ancillary components to accommodate expansion of the water.

Principle of Operation

In a closed heating system water cannot be compressed so any increase in volume, created by an increase in temperature, has to be accommodated by an expansion vessel.

When water is cold, the pre-charge pressure in the expansion vessel forces the diaphragm against the the inside of the vessel towards the inlet.
As the temperature increases, the expanded water volume pushes against the diaphragm creating additional volume for the water to enter.
When the temperature decreases, the pre-charge pressure forces the water from the expansion vessel and back into the main heating system.
This maintains a constant pressure within the heating system helping to reduce energy consumption.

Not suitable for potable water

The Robokit Extra consists of an expansion vessel with a sealed system kit which contains;

  • 18L Reflex Expansion vessel
  • Wall mounting bracket
  • Quattro 4 way connector
  • Safety relief valve complete with pressure gauge
  • Filling loop

NOTE: The expansion vessel must be sized to suit the volume change of water within the heating system.


  • System Flexibility - due to component siting alternatives.
  • Cost Savings - due to considerably reduced installation time.
  • No Feed and Expansion Tank - hence avoiding “pumping over” problems, risk of freezing up etc.
  • Longer Life - due to virtual elimination of corrosion problems.
  • Noise Reduction - due to higher system pressure, boiler noise (localised heating) is significantly reduced or eliminated.
  • Low Maintenance Costs - as equipment is virtually maintenance free, other than for periodic operational checks.
Read more
Product Type
Heating Expansion Vessel
Weight (KG)
Manufacturers Warranty
2 Years (Subject to Manufacturers T&C's)
Manufacturers brochure PDF File
Customer Questions
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