Generator Exhaust Extension Kit

Our generator exhaust extension kits are ideal for backup generators where exhaust gases must be safely removed from confined spaces.

Common applications are where generators are installed inside sheds or under houses, in remote or off-grid environments.

Available in common industry sizes from 1.5” through to 2.5”. Larger sizes available on request.

Each kit comes with enough materials for a simple, clamp-together installation. You may have some leftover items - don't feel you need to use everything, but we've done most of the thinking for you!

This is only an exhaust extension. If you want to purify the exhaust gases consider a diesel oxidation catalyst (DOC) or diesel particulate filter (DPF). These remove harmful gases including carbon monoxide, hydrocarbons and diesel particulate matter. Click here to request a quote on your preferred size. 

Please read all the below instructions carefully: most of your questions will be answered below. With some planning, purchasing and installing your generator exhaust extension kit should be a simple task.

1. Determine exhaust outlet size
2. Use some grid paper to design your own system
3. Compare parts required with list of parts included in the kit
4. Add in any special requests to the notes field
5. Order your kit!

Included in Kit

• 3 x 1.0m rigid aluminised steel exhaust tube sections, with 2 sections expanded 1 end so they can be clamped together
• 0.3m x flexible stainless steel exhaust tube
• 1 x aluminised steel 90° mandrel bend
• 1 x zinc plated silent raincap
• 2 x stainless steel clamps for flexible tube (either lap clamps or uni-bolt clamps depending on pipework size)
• 1 x zinc plated clamp for exhaust outlet
• 3 x zinc plated clamps for use as brackets
• 2 x horizontal mount, double-ended universal brackets
• 1 x tube of exhaust sealant
• Expansion of bend to desired ID if required (for generator exhaust outlet)
• Installation guide.

Design Your Own System

Before purchasing a Generator Exhaust Extension Kit, we recommend you draw a quick diagram on grid paper or similar, to work out where you are going to run your exhaust system after it exits the generator, to the point where it exits the building. 

Make sure you have enough tube length, you can make the joins work (allow 5-10cm overlap for every clamp joint), and that you have an elbow for every direction change. 

Keep your exhaust system as straight and as short as possible - backpressure increases as the length and number of bends increase. Too much backpressure can make the generator perform less effectively, and potentially damage the engine.

We recommend selecting the closest size extension kit to the generator outlet size.  Examples:

• If the outlet of the generator is 63mm, purchase the 2½" (63mm) extension kit. We will then expand 1 end of the first bend to 63mm ID, so it can slide over your existing generator outlet.
• If the outlet of the generator is 55mm, purchase the 2¼" (57mm) extension kit. We will then expand 1 end of the first bend to 55mm ID.
  

Remember that exhaust tube is measured by the outside diameter, and has a 1.6mm wall thickness (e.g. 51mm tube has an ID of approximately 47.8mm). Depending on the outlet size, we may not even need to expand 1 end of the first bend. 

If you need to shorten any tube sections, exhaust tube is light gauge (1.6mm wall thickness) and can be cut with a cold saw, drop saw, grinder with cut-off wheel or pipe cutter. 

Additional items for your exhaust extension kit can be purchased separately.

Typical Installation Guide

1. Attach 90° mandrel bend (expanded end if supplied) to exhaust outlet and rotate for vertical or horizontal application as required. Secure with clamp.
2. Slide flexible exhaust tube section over mandrel bend and secure with clamp.
3. Insert remaining rigid exhaust tube into flexible exhaust tube. Cut to length if required, and secure with clamps.
4. Ensure exhaust extension is adequately fastened to wall using supplied brackets or clamps as required. Do not use brackets before the flexible tube section as this is designed to absorb any vibrations made by the generator.
5. Ensure tube is appropriately weatherproofed (e.g. Dektite flashing) and heat-insulated (e.g. silicone coated fibreglass hose cover) where the exhaust extension exits the building.
6. Attach and fasten zinc plated silent raincap (exterior of building).
7. If desired, use exhaust silicone sealant on all connection points for a leakproof seal.