Heating
Expansion Vessels

Fabricated Products offer a complete range of expansion vessels to meet the requirements of most heating or cooling systems.

Design

  • The vessel is fabricated by welding the various sections together which results in a very reliable structure suitable for internal pressures up to 6 bar
  • Non-replaceable diaphragm
  • Epoxy coated in grey
  • Suitable for temperatures up to 120°C, resistant to ethylene or propylene glycol mixtures and has low gas permeability
  • Our expansion vessels are all tested according to the Pressure Systems Directive

How it works

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 forces the diaphragm against the tank 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 tank and back into the main heating system.

This maintains a constant pressure within the heating system helping to reduce energy consumption.

Heating Expansion Vessels
Technical Specification 8 - 140 litres
Max. working pressure: 8 to 35 litres / 3 bar
50 to 140 litres / 6 bar
Test Pressure: 1.5 x max working pressure
Max. flow operating temp: 120°C
Max. vessel operating temp: 70°C
Factory air pre-charge: 1.5 bar - nitrogen
Technical Specification 200 - 800 litres
Max. working pressure: 6 bar
Max. flow operating temp: 120°C
Max. vessel operating temp: 70°C
Factory air pre-charge: 1.5 bar - nitrogen
Materials
Component Material
Shell Carbon Steel
Connectionss Carbon Steel
Diaphragm Synthetic rubber compound
Coating Powder epoxy

Technical Data

Expansion vessels for heating systems are manufactured to meet the requirements of PED 97/23/EC Directive and BS EN 13831: 2007 'Closed expansion vessels with built in diaphragm for installation in water'.

8 - 25 litres
Model No.Capacity (lt)ØD (mm)H (mm)Connection (c)Weight (kg)
EXPHTG-8 8 272 235 R 3/4 1.7
EXPHTG-12 12 272 315 R 3/4 2.3
EXPHTG-18 18 308 365 R 3/4 2.8
EXPHTG-25 25 308 485 R 3/4 3.5
Heating Expansion Vessels
35 - 140 litres
Model No.Capacity (lt)ØD (mm)H (mm)h (mm)Connection (c)Weight (kg)
EXPHTG-35 35 376 465 130 R 3/4 5.7
EXPHTG-50 50 441 495 175 R 3/4 7.5
EXPHTG-80 80 512 570 175 R1 9.9
EXPHTG-100 100 512 680 175 R1 11.2
EXPHTG-140 140 512 895 175 R1 14.5
CE Marked
Heating Expansion Vessels
200 - 800 litres
Model No.Capacity (lt)ØD (mm)H (mm)h (mm)Connection (c)Weight (kg)
EXPHTG-200 200 634 760 205 R1 37
EXPHTG-250 250 634 890 205 R1 45
EXPHTG-300 300 634 1090 235 R1 52
EXPHTG-400 400 740 1090 245 R1 65
EXPHTG-500 500 740 1290 245 R1 79
EXPHTG-600 600 740 1530 245 R1 85
EXPHTG-800 800 740 1995 245 R1 103
CE Marked
Heating Expansion Vessels
Accessories
EXPKIT8-80 Sealed System Kit (8-80 Litre)
EXPBKT1 Heating Vessel Mounting Bracket 8-25ltr
Air and Dirt Separators Clients 1
Air and Dirt Separators Clients 2
Air and Dirt Separators Clients 3
Air and Dirt Separators Clients 4
Air and Dirt Separators Clients 5
Air and Dirt Separators Clients 6
Air and Dirt Separators Clients 7
Air and Dirt Separators Clients 8