ThermoWave TWB-2LX 2 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-4LX 4 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-8LX 8 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-12LX 12 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-18LX 18 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-24LX 24 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-35LX 35 L inline DHW expansion vessel, Global Water Solutions
ThermoWave TWB-60LV 60 L vertical DHW expansion vessel with base, Global Water Solutions
ThermoWave TWB-24LX three-quarter view, Global Water Solutions DHW expansion vessel
ThermoWave TWB-24LX top view, showing the stainless steel water connection

ThermoWave steel DHW expansion vessel by Global Water Solutions

Format
Model
Regular price€21,24
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Shipping calculated at checkout.

  • 4 in stock
  • Backordered, shipping soon

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  • Rights intact: 14 days of withdrawal from receipt for most products—subject to the legal exceptions you will see below, such as goods made to your specifications—and a 3-year legal warranty of conformity, under the terms of the TRLGDCU.
  • Conformity with the description: we guarantee that the equipment will correspond to the published technical description and what one could reasonably expect from it (arts. 115 et seq. TRLGDCU). Images and videos are for guidance only: the manufacturer may supply a more recent revision of the product or introduce minor aesthetic, packaging, or firmware changes, without this constituting a lack of conformity as long as the described characteristics and performance are maintained.
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Responsible use and your part

  • If you are thinking of returning it, keep it as you received it: without installing or activating it, with its seals, accessories, and packaging intact. This is how to ensure a full refund, without deductions.
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  • The same item must be returned: withdrawal requires returning the supplied unit. Different equipment, or equipment with prior use, age, or wear prior to purchase, does not constitute a valid withdrawal.
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  • Delivery of bulky goods: delivery is made to the curb. B2C: transport risk is ours until physical delivery (art. 66 ter); we recommend noting visible damages on the delivery note and notifying us of breakages within 24-48 hours with photographs to activate the insurance. B2B: inspection and notation on the delivery note are mandatory; hidden damages must be reported within 24 hours (art. 366 CCom). Unjustified rejection or incorrect shipping information will entail the actual outbound and return costs (approx. €85-550 for heavy machinery).

Made to your measure (Advanced Pre-Assembly)

  • If your order includes equipment, racks, hydraulic assemblies, or technical rooms made or configured according to your specifications (permanent joints, custom cuts or wiring, parameterization, pressure testing), these are custom goods without the right of withdrawal from the conclusion of the contract (art. 103.c TRLGDCU; CJEU Case C-529/19), which is informed before purchasing and documented in the signed Order Note. A test you request without permanent modification retains your right of withdrawal, with only the actual loss of value caused by that test being deducted. Would you prefer to receive it tested, configured, and ready to connect, without assuming these risks? Contract our Advanced Pre-Assembly or the prior technical audit.

If you are purchasing as a business or professional (B2B)

  • The transaction is governed by the Commercial Code: firm sale, without the right of withdrawal; notification of defects within 4 days (apparent) / 30 days (hidden), arts. 336 and 342. Q-TECH acts as a distributor and excludes indirect damages, loss of profit, and data loss, limited to the price of the equipment, without prejudice to the manufacturer's commercial warranty.

Product warnings v1.0 · June 2026. Information summary; the complete and binding conditions are those published at q-tech.es.

10 bar expansion vessel for your domestic hot water

The Global Water Solutions ThermoWave expansion vessel absorbs the expansion of domestic hot water and stops the safety valve from discharging water. Q-Tech integrates it into your pre-assembled plant room, connected and tested in our workshop together with the cylinder or heat pump.

Summary

Type Steel expansion vessel with fixed diaphragm and polypropylene liner
Brand and model Global Water Solutions ThermoWave, from TWB-2LX to TWB-60LV
Use Domestic hot water (DHW) in homes and light commercial buildings
Maximum pressure 10 bar
Maximum temperature 90 °C
Formats Inline (2 to 35 L) and vertical with base (60 L)
Connection ¾" BSPT stainless steel
Q-Tech installation Integrated and tested in our workshop within your plant room

What is the ThermoWave?

The Global Water Solutions ThermoWave is a steel expansion vessel for domestic hot water. The water only touches a virgin polypropylene liner and the butyl diaphragm, never the steel. It is rated for 10 bar and up to 90 °C.

What problem does it solve?

As the water in the water heater or cylinder heats up, its volume increases and pressure rises. Without a vessel, the safety valve discharges hot water, wasting both water and energy.

A heating vessel is not suitable here, because the water would touch the steel. The ThermoWave is made from 2 to 60 litres, with the water kept away from the metal.

Technical data

Manufacturer Global Water Solutions
Series ThermoWave
Shell Steel with two-layer polyurethane paint, almond colour
Diaphragm High-grade butyl, fixed
Liner Virgin polypropylene
Water connection Stainless steel, patented, ¾" BSPT
Air valve O-ring sealed cap
Maximum working pressure 10 bar
Factory pre-charge 1.9 bar
Maximum working temperature 90 °C
Quality Manufactured under ISO 9001, according to the manufacturer

Models and data by variant

Model Format Volume Connection Height Diameter Gross weight
TWB-2LX Inline 2 L ¾" BSPT 206 mm 126 mm 1.2 kg
TWB-4LX Inline 4 L ¾" BSPT 258 mm 162 mm 1.6 kg
TWB-8LX Inline 8 L ¾" BSPT 310 mm 202 mm 2.3 kg
TWB-12LX Inline 12 L ¾" BSPT 364 mm 230 mm 3.1 kg
TWB-18LX Inline 18 L ¾" BSPT 364 mm 279 mm 4.0 kg
TWB-24LX Inline 24 L ¾" BSPT 444 mm 290 mm 5.3 kg
TWB-35LX Inline 35 L ¾" BSPT 478 mm 318 mm 7.1 kg
TWB-60LV Vertical 60 L ¾" BSPT 619 mm 398 mm 11.6 kg

Compatibility and limits

  • Suitable for potable water: the water does not touch the steel thanks to the polypropylene liner.
  • Up to 10 bar and 90 °C, according to the manufacturer.
  • Pre-charge is set to the cold water inlet pressure, with the vessel empty.
  • Inline models are supported by the pipework or a wall bracket, sold separately; the vertical model stands on its base.

When this product is not the right choice

Product When to choose it Maximum pressure Maximum temperature
HeatWave Closed-loop heating circuits 6 bar 99 °C
SolarWave Solar thermal circuits 10 bar 130 °C
PressureWave Cold water booster pump sets 10 bar 90 °C

To compare with other brands, see the Expansion vessels and pressure tanks collection.

Frequently asked questions

Can it be used for heating?

It can, but for closed-loop heating the dedicated option is the HeatWave.

Which volume do I need?

It depends on the cylinder volume, the water temperature and the mains pressure. We can help you size it in a technical call.

Do I need to adjust the pre-charge?

Yes. Set it to the cold water inlet pressure, with the vessel empty, following the manufacturer's manual linked below.

Where is it installed?

On the cold water inlet of the water heater or cylinder, following the manufacturer's manual.

What is the delivery time?

We have it in stock at our warehouse. If none were left, we would order it urgently and tell you the lead time.

Q-Tech installation and support

Q-Tech integrates the ThermoWave into your pre-assembled plant room, tested in our workshop with the cylinder or heat pump: it arrives on site ready to connect. More information on Advanced Pre-Assembly.

If your installation is already in place, book the on-site hourly Expert Technician or a technical call. More equipment in Expansion vessels and pressure tanks.

Documentation

Availability and lead times: this item is in stock at our warehouse. Occasionally, depending on the time of year, the stock update may contain an error. If no units are available when you place your order, we will order it urgently and inform you immediately of the updated delivery time.

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