At some point, you may need a chiller rental to fulfil a function or two. Whether you need it in the long-term for your business or you’ll need one for a special event, chiller rentals are incredibly useful. They give you access to top-tier cooling technology without needing to purchase them, and you can choose from a wide range of chillers. While you’ll likely prioritise the chiller with the best specifications, you’ll need to keep in mind other factors, such as the size of the pipe that the chiller needs to run. 

For your chiller rental to run efficiently, it’s important to learn the general guidelines on pipe sizing. It will help you optimise pipe sizes and get the most out of your chiller hire. Here’s what you need to know: 

Pipe Diameter Must Be Equal to The Discharge Line Connection’s Diameter 

The first rule of pipe sizing for chiller hire is that the pipes must never have a smaller diameter than the chiller’s discharge line connection diameter. This rule also applies to cooling towers and pumps. It’s imperative to keep this rule in mind if you need to rent a chiller for an emergency. Many people tend to forget to check pipe sizes since they focus more on continuing chiller operations. 

You must consider the pipe diameter because the rental chiller will release fluid into a pipe system that becomes narrower due to a thinner diameter than the discharge pipe. As a result, you’ll experience fluid back-pressure in the system, harming pipe connections and pumps. A smaller diameter can also impact the chiller fluid’s energy levels and obstruct the unit’s efficiency and cooling ability. To avoid this, ensure that the chiller discharge outlet diameter is the same size as the system’s pipes. 

Get Discharge Outlets With Smaller Diameters 

If your system experiences a high flow rate or long piping runs, then you’ll want to prioritise renting a chiller that has discharge outlets with smaller diameters than the pipe. Doing this will prevent fluid from losing energy by flowing faster, which often happens when it flows through exceptionally long piping. Smaller discharge outlets will cause the fluid to run more steadily to ensure it preserves energy. 

Bypass Piping Must Be the Same Size as Supply Piping 

Lastly, if you need an external bypass for your chiller hire, it must be the same size as the supply piping. To ensure it operates to the best of its ability, install a gate valve in the bypass line, which will regulate fluid flow with a linear dam that will connect to the line. Having a gate allows you more precise control over the fluid flow in the line, enabling you to adjust it to optimise the chiller’s operations as best as you can. 


Chiller hire offers a world of convenience when you need a cooling solution for your business, an emergency, or other applications. However, it’s essential to keep piping in mind, as it should never be neglected or sidelined. You must source your chiller from a company that can help you determine if the chiller you want to rent is compatible with your existing piping. By following our guide and trusting a reputable company for your chiller rental, you’ll find a perfect appliance for your needs. 

London Climate Hire is a team of HVAC specialists offering chiller rentals for London and surrounding counties. We have a wealth of industry knowledge and experience that allows us to provide you with a cost-effective, immediate response installation to help you resume business operations. Call us now at 0800 270 7006 for an instant quote!