Expansion Tanks

Horizontal Expansion Tanks

Horizontal expansion vessels are membrane pressure vessels whose shell lies horizontally; they absorb the expansion volume of a closed circuit in boiler rooms with limited height, on pipe racks or under equipment, wherever a vertical vessel will not fit.

The range includes PN10 horizontal vessels in 24, 50 and 100 litre volumes. The EPDM membrane inside takes up the additional volume from heated water by compressing the gas cushion, and returns the same volume to the circuit when the water cools. The vessel is supplied with a powder-coated steel shell, a gas side filled with dry air and the factory pre-charge stated on the label.

24–100 Lhorizontal volumes

PN10pressure class

+70 °Cmembrane continuous temperature

EPDMstandard membrane

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Main Applications

Boiler rooms with limited ceiling height
Packaged heat centres and heat pump units
Fan-coil and closed cooling circuits
Placement on pipe racks or under platforms
Small and medium commercial buildings

Technical Data

Shell type	Horizontal cylindrical
Volumes	24 L · 50 L · 100 L
Pressure class	PN10
Max. vessel temperature	+110 °C (+70 °C on domestic water)
Membrane	EPDM; butyl optional
Membrane continuous temperature	Up to +70 °C
Gas side	Dry air; nitrogen optional
Fluid	Water or water with up to 50% glycol
Minimum pressure	0 bar
Pre-charge	On the label; adjusted on site in operation
Connection and mounting	Depending on model
Shell surface	Electrostatic powder-coated outside, untreated inside

Material Options

Part	PN10 · 24 L	PN10 · 50 L	PN10 · 100 L
Shell	Steel	Steel	Steel
Exterior coating	Electrostatic powder coating	Electrostatic powder coating	Electrostatic powder coating
Membrane	EPDM	EPDM	EPDM
Gas charge	Dry air	Dry air	Dry air
Connection size	Depending on model	Depending on model	Depending on model
Mounting feet or bracket	Depending on model	Depending on model	Depending on model

Maintenance note: If water comes out when the gas valve is pressed briefly, the membrane is damaged and must be replaced by an authorised service. Pre-charge is measured with the system drained and cold. A lockable valve on the connection to isolate the vessel and union fittings for easy removal are recommended.

Advantages

Low Height

The shell lies horizontally.
Installation where ceilings are low.

Compact Volumes

24–100 L range.
Suits small and medium circuits.

Closed-Circuit Balance

Pressure fluctuation is reduced.
The safety valve does not open needlessly.

Ready Pre-Charge

Gas side charged at the factory.
Only fine adjustment on site.

Separated Fluid

Water does not touch the gas cushion.
Air is kept out of the circuit.

Construction and Design Features

Horizontal cylindrical steel shell
EPDM membrane inside the shell
Gas filling valve and water connection
Powder-coated exterior
Identification label with volume and pressure data

Send the circuit volume, operating temperatures and safety valve setting through the Request a Quote form; we will confirm the horizontal vessel volume.

How to Choose?

Measure the spaceCheck there is enough room for the vessel length and connection direction.
Calculate expansionFind the additional volume from circuit water content and temperature difference.
Check the pressure limitConfirm the final pressure stays below PN10 and the safety valve setting.
Choose the volumeSelect the 24, 50 or 100 litre vessel that covers the calculated value.
Leave accessInstall so that the gas valve and label can be reached.

Complementary Products

Booster Sets & Hydrophores Flanged Safety Valves Rubber Expansion Joints Threaded Y-Type Strainers Temperature Measurement and Control Equipment Threaded Fittings

Why ORFA?

Since 1985Over 40 years of experience in supplying industrial installation equipment.

Technical ConsultancyWe help with siting and expansion volume calculations.

Delivery from Stock24, 50 and 100 litre horizontal vessels are delivered from stock.

Pre-Charge CheckTechnical support for pre-charge setting before commissioning and for periodic checks.

In This Group

Other Expansion Tanks

Vertical Expansion Tanks

Vertical expansion tanks are floor-standing diaphragm tanks that absorb the thermal expansion of water in closed heating, cooling and booster systems.

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