FlexEJ Products People

24hr Shipping
On all stock items ordered.
Mon-Thur by 2pm, 10am Fridays

Design & Manufacturing
Full in-house design & manufacture to EN / ASME / PED.

ISO14001 Accreditation
FlexEJ has an accredited Environmental Management System.

HVAC Rubber Bellows

Designed for water applications in building services.

FlexEJ offers two ranges for this market: Our value HVAC range which is suited to lower temperatures and pressures and the Elaflex range which features WRAS approval, high temperature durability and many more options:

Selecting Rubber Expansion Joints​

HVAC Rubber bellows Temperature & Pressure Temperature is the most critical as it directly influences the choice of rubber – but also the actual pressure capability of the bellows. The stated maximum rated pressure is maintained up to around 50ºC for most rubber bellows, for higher temperatures check the data in the Range tab.

FlexEJ’s HVAC Rubber Bellows


FlexEJ has the following ranges of HVAC Rubber Bellows available:

HVAC flanged rubber bellows

DN32 to DN250

HVAC flanged rubber bellows

HVAC FLANGED RUBBER BELLOWS

When a value HVAC bellow will meet your requirements
FlexEJ’s Value Flanged rubber bellows are ideal for applications at lower temperatures and pressures and where WRAS drinking water approval is not required. Available in lengths of 106, 130 and 150mm (200mm at DN250) all flanged PN16, tied or untied, DN32 to DN250. All of these are available from our web shop on 24 hour delivery.

Union end rubber bellows

DN20 to DN65

Union end rubber bellows

UNION END RUBBER BELLOWS

EPDM rubber with galvanised cast iron BSP union ends
FlexEJ’s Value Union rubber bellows are ideal for smaller diameter applications at lower temperatures and pressures and where WRAS drinking water approval is not required. Length of 200mm (240mm at DN65) all with BSP Unions, DN20 to DN65. All of these are available from our web shop on 24 hour delivery.

Elaflex HVAC Rubber Bellows

DN25 to DN1000

Elaflex HVAC Bellows range

ELAFLEX HVAC BELLOWS

RedSpot, RedBand and Rotex

The Elaflex range, manufactured in Germany, offers three types of rubber bellows designed for HVAC services. RedSpot is a highly flexible low pressure design with WRAS approval; RedBand is also WRAS approved and designed for higher pressures and temperatures; Rotex is a DIN4809 approved rubber bellows designed specifically for high temperature services. All Elaflex rubber bellows are available with a wide range of flange drillings, tied or untied. All three Elaflex ranges with PN16 flanges DN25 to DN150, tied and untied, are available with 24 hour shipping from our web shop.

HVAC Rubber Bellows Finders and Calculators


We have a couple of easy to use tools and calculators to help you find the best HVAC rubber expansion bellows from our next-day delivery stock items. Our Thermal Expansion Calculator for Piping helps you estimate the increase in length of a pipe run with temperature.

Our Advanced Bellows Finder is a quick way to navigate our stock range of bellows, both metal and rubber. With just a few choices you can arrive at the appropriate selection – criteria include pipe size, type, media compatibility, installation length, pressure rating, pipe connection type, conformance and movement axial, lateral and angular. All the products are in the online store with 24hr shipping as standard. If you’re not sure what flange you need our handy Flange Finder should also be useful.

Stock HVAC Rubber Bellows Finder

Do search for HVAC rubber bellows by pipe size, intended media and/or connection hardware to see FlexEJ’s HVAC stock bellows options below but don’t hesitate to call us on 01384 881188 or email us for more bespoke or OEM options or if you need any advice at all.

DN20 (¾″) FlexEJ Union EPDM Rubber Bellows - Length 200 mm
DN20 (¾″) FlexEJ Union EPDM Rubber Bellows – Length 200 mm
DN25 (1″) FlexEJ Union EPDM Rubber Bellows - Length 200 mm
DN25 (1″) FlexEJ Union EPDM Rubber Bellows – Length 200 mm
DN32 (1¼″) Elaflex RedSpot EPDM Rubber Bellows - Length 130 mm
DN32 (1¼″) Elaflex RedSpot EPDM Rubber Bellows – Length 130 mm

Can't quite find the right bellow?
Try our Advanced Bellows Finder

Or call our expert team on +44 (0) 1384 881188. We'll be glad to help.

HVAC Rubber Product Comparison Chart


Which HVAC rubber bellows is the best option for your application? Three potential alternatives to consider:

Can't see what you want? Need help?
Call us. Or use Live Chat.

For instant advice. We can custom-design and engineer almost any expansion joint you need for delivery in the UK or worldwide. Call our expert team on +44 (0) 1384 881188 Or email us sales@flexej.co.uk

Frequently Asked Questions

A. Yes. FlexEJ holds a large stock of the most popular sizes and types of Elaflex rubber bellows as well as our HVAC value bellows range. We also hold stock of the most popular metal bellows for HVAC. Many of these items are available on 24hr delivery from our online web shop. We can also manufacture to order. For sales assistance please contact us or use our Live Chat facility.

A. Our Flange Finder contains details for many common flanges. Typically, to be able to make the identification you need to know the bore size or outside diameter and number of bolts. For technical assistance contact us or use our Live Chat facility.

A. Please refer to our guidelines for installation, anchoring & guides. They are available in the Downloads section of this website: Elaflex Rubber Bellows Installation Instructions and FlexEJ Metal Bellows Installation Instructions. For technical assistance please contact us or use our Live Chat facility.

A. FlexEJ Value HVAC and Elaflex rubber bellows are stocked in a number of standard lengths from 105mm to 300mm, a summary of lengths, diameters and types can be found on each product page. We also offer fully engineered rubber bellows which are available in custom lengths to suit the application. You can use our bellows finder to find the most suitable product. For technical assistance please contact us or use our Live Chat facility.

A. Yes, if you have the details we can normally offer an equivalent, our FAQ here gives the information we will need for a full selection. For technical assistance please contact us or use the Live Chat link on this page.

A. To identify an existing expansion joint we need to know: nominal bore, overall length and flange type plus service, temperature, pressure and required movement if known. Try our Flange Finder to help identify the flange and you can send us a picture of the existing part using the Contact us form. For technical assistance please contact us or use the LIVE CHAT link on this page.

A. Yes, our Elaflex ERV-R and ERP rubber bellows have WRAS, DVGW and ACS approval for drinking water, see our Elaflex pages for more information. The Safetech manufactured to order rubber bellows can be supplied with WRAS approved EPDM linings. Our MRCA copper ended metal expansion joints also have WRAS approval. For technical assistance please contact us or use the LIVE CHAT link on this page.

Please visit our full FAQ page to see all our frequently asked questions.